From 2af766186df3663005dd5e01f4e0d4e98bbff7b6 Mon Sep 17 00:00:00 2001
From: Harriet Brown <harriet.brown@stfc.ac.uk>
Date: Thu, 5 Mar 2020 13:31:06 +0000
Subject: [PATCH] Replace header guards in DataHandling with pragma once

This commit replaces all header guards in DataHandling with #pragma once
---
 .../inc/MantidDataHandling/AppendGeometryToSNSNexus.h       | 5 +----
 .../DataHandling/inc/MantidDataHandling/AsciiPointBase.h    | 5 +----
 .../DataHandling/inc/MantidDataHandling/BankPulseTimes.h    | 5 +----
 .../inc/MantidDataHandling/CheckMantidVersion.h             | 5 +----
 .../DataHandling/inc/MantidDataHandling/CompressEvents.h    | 5 +----
 .../inc/MantidDataHandling/CreateChunkingFromInstrument.h   | 5 +----
 .../inc/MantidDataHandling/CreatePolarizationEfficiencies.h | 5 +----
 .../MantidDataHandling/CreatePolarizationEfficienciesBase.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/CreateSampleShape.h | 5 +----
 .../inc/MantidDataHandling/CreateSimulationWorkspace.h      | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/DataBlock.h   | 5 +----
 .../inc/MantidDataHandling/DataBlockComposite.h             | 6 ++----
 .../inc/MantidDataHandling/DataBlockGenerator.h             | 5 +----
 .../inc/MantidDataHandling/DefaultEventLoader.h             | 5 +----
 .../DataHandling/inc/MantidDataHandling/DefineGaugeVolume.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/DeleteTableRows.h   | 5 +----
 .../DataHandling/inc/MantidDataHandling/DetermineChunking.h | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/DllConfig.h   | 5 +----
 .../DataHandling/inc/MantidDataHandling/DownloadFile.h      | 5 +----
 .../inc/MantidDataHandling/DownloadInstrument.h             | 5 +----
 .../inc/MantidDataHandling/EventWorkspaceCollection.h       | 5 +----
 .../inc/MantidDataHandling/ExtractMonitorWorkspace.h        | 5 +----
 .../MantidDataHandling/ExtractPolarizationEfficiencies.h    | 5 +----
 .../inc/MantidDataHandling/FilterEventsByLogValuePreNexus.h | 6 ++----
 .../inc/MantidDataHandling/FindDetectorsInShape.h           | 5 +----
 .../DataHandling/inc/MantidDataHandling/FindDetectorsPar.h  | 5 +----
 .../inc/MantidDataHandling/GenerateGroupingPowder.h         | 5 +----
 .../DataHandling/inc/MantidDataHandling/GroupDetectors.h    | 5 +----
 .../DataHandling/inc/MantidDataHandling/GroupDetectors2.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/H5Util.h      | 5 +----
 .../DataHandling/inc/MantidDataHandling/ISISDataArchive.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/ISISRunLogs.h | 5 +----
 .../MantidDataHandling/JoinISISPolarizationEfficiencies.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/Load.h        | 5 +----
 .../inc/MantidDataHandling/LoadANSTOEventFile.h             | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadANSTOHelper.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadAscii.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadAscii2.h  | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadAsciiStl.h      | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadBBY.h     | 5 +----
 .../inc/MantidDataHandling/LoadBankFromDiskTask.h           | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadBinaryStl.h     | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadCalFile.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadCanSAS1D.h      | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadCanSAS1D2.h     | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadDaveGrp.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadDetectorInfo.h  | 5 +----
 .../inc/MantidDataHandling/LoadDetectorsGroupingFile.h      | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadDiffCal.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadDspacemap.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadEMU.h     | 5 +----
 .../inc/MantidDataHandling/LoadEmptyInstrument.h            | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadEventNexus.h    | 5 +----
 .../inc/MantidDataHandling/LoadEventNexusIndexSetup.h       | 5 +----
 .../inc/MantidDataHandling/LoadEventPreNexus2.h             | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadFITS.h    | 5 +----
 .../inc/MantidDataHandling/LoadFullprofResolution.h         | 5 +----
 .../inc/MantidDataHandling/LoadGSASInstrumentFile.h         | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadGSS.h     | 6 ++----
 .../DataHandling/inc/MantidDataHandling/LoadGeometry.h      | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadHFIRSANS.h      | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadHelper.h  | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadIDFFromNexus.h  | 5 +----
 .../inc/MantidDataHandling/LoadILLDiffraction.h             | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadILLIndirect2.h  | 5 +----
 .../inc/MantidDataHandling/LoadILLPolarizationFactors.h     | 5 +----
 .../inc/MantidDataHandling/LoadILLReflectometry.h           | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadILLSANS.h | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadILLTOF2.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadISISNexus2.h    | 5 +----
 .../MantidDataHandling/LoadISISPolarizationEfficiencies.h   | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadInstrument.h    | 5 +----
 .../inc/MantidDataHandling/LoadInstrumentFromNexus.h        | 5 +----
 .../inc/MantidDataHandling/LoadInstrumentFromRaw.h          | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadIsawDetCal.h    | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadLLB.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadLog.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadMLZ.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadMappingTable.h  | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadMask.h    | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadMcStas.h  | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadMcStasNexus.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadMuonLog.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadMuonNexus.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadMuonNexus1.h    | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadMuonNexus2.h    | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadNGEM.h    | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadNXSPE.h   | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadNXcanSAS.h      | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadNexus.h   | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadNexusLogs.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadNexusMonitors.h | 5 +----
 .../inc/MantidDataHandling/LoadNexusMonitors2.h             | 5 +----
 .../inc/MantidDataHandling/LoadNexusProcessed.h             | 5 +----
 .../inc/MantidDataHandling/LoadNexusProcessed2.h            | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadOff.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadPDFgetNFile.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadPLN.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadPSIMuonBin.h    | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadParameterFile.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadPreNexus.h      | 5 +----
 .../inc/MantidDataHandling/LoadPreNexusMonitors.h           | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadQKK.h     | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadRKH.h     | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadRaw3.h    | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadRawBin0.h | 6 ++----
 .../DataHandling/inc/MantidDataHandling/LoadRawHelper.h     | 6 ++----
 .../DataHandling/inc/MantidDataHandling/LoadRawSpectrum0.h  | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadSESANS.h  | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadSINQFocus.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadSNSspec.h | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadSPE.h     | 5 +----
 .../inc/MantidDataHandling/LoadSampleDetailsFromRaw.h       | 5 +----
 .../inc/MantidDataHandling/LoadSampleEnvironment.h          | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadSampleShape.h   | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadSassena.h | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadSpec.h    | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadSpice2D.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadSpiceAscii.h    | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadSpiceXML2DDet.h | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadStl.h     | 6 ++----
 .../DataHandling/inc/MantidDataHandling/LoadStlFactory.h    | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/LoadSwans.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/LoadTBL.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/LoadTOFRawNexus.h   | 5 +----
 .../DataHandling/inc/MantidDataHandling/MaskDetectors.h     | 5 +----
 .../inc/MantidDataHandling/MaskDetectorsInShape.h           | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/MaskSpectra.h | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/MeshFileIO.h  | 6 ++----
 .../inc/MantidDataHandling/ModifyDetectorDotDatFile.h       | 5 +----
 .../inc/MantidDataHandling/MoveInstrumentComponent.h        | 5 +----
 .../inc/MantidDataHandling/NXcanSASDefinitions.h            | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/NexusTester.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/ORNLDataArchive.h   | 5 +----
 .../inc/MantidDataHandling/PDLoadCharacterizations.h        | 5 +----
 .../inc/MantidDataHandling/ParallelEventLoader.h            | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/PatchBBY.h    | 5 +----
 .../DataHandling/inc/MantidDataHandling/PrecompiledHeader.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/ProcessBankData.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/RawFileInfo.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/ReadMaterial.h      | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/RemoveLogs.h  | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/RenameLog.h   | 5 +----
 .../inc/MantidDataHandling/RotateInstrumentComponent.h      | 5 +----
 .../DataHandling/inc/MantidDataHandling/RotateSource.h      | 5 +----
 .../inc/MantidDataHandling/SampleEnvironmentFactory.h       | 5 +----
 .../inc/MantidDataHandling/SampleEnvironmentSpec.h          | 5 +----
 .../inc/MantidDataHandling/SampleEnvironmentSpecParser.h    | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveANSTOAscii.h    | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/SaveAscii.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveAscii2.h  | 5 +----
 .../inc/MantidDataHandling/SaveBankScatteringAngles.h       | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveCSV.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveCalFile.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveCanSAS1D.h      | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveCanSAS1D2.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveDaveGrp.h | 5 +----
 .../inc/MantidDataHandling/SaveDetectorsGrouping.h          | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveDiffCal.h | 5 +----
 .../inc/MantidDataHandling/SaveDiffFittingAscii.h           | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveDspacemap.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveFITS.h    | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveFocusedXYE.h    | 6 ++----
 .../inc/MantidDataHandling/SaveFullprofResolution.h         | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveGDA.h     | 5 +----
 .../inc/MantidDataHandling/SaveGSASInstrumentFile.h         | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveGSS.h     | 6 ++----
 .../inc/MantidDataHandling/SaveILLCosmosAscii.h             | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveISISNexus.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveIsawDetCal.h    | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveMask.h    | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveNISTDAT.h | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveNXSPE.h   | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveNXTomo.h  | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveNXcanSAS.h      | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveNexus.h   | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveNexusESS.h      | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveNexusGeometry.h | 5 +----
 .../inc/MantidDataHandling/SaveNexusProcessed.h             | 5 +----
 .../inc/MantidDataHandling/SaveOpenGenieAscii.h             | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/SavePAR.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SavePDFGui.h  | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SavePHX.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveParameterFile.h | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveRKH.h     | 5 +----
 .../DataHandling/inc/MantidDataHandling/SaveRMCProfile.h    | 5 +----
 .../inc/MantidDataHandling/SaveReflCustomAscii.h            | 5 +----
 .../inc/MantidDataHandling/SaveReflThreeColumnAscii.h       | 5 +----
 .../inc/MantidDataHandling/SaveReflectometryAscii.h         | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveSESANS.h  | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveSPE.h     | 5 +----
 .../inc/MantidDataHandling/SaveSampleEnvironmentAndShape.h  | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveStl.h     | 6 ++----
 Framework/DataHandling/inc/MantidDataHandling/SaveTBL.h     | 5 +----
 .../inc/MantidDataHandling/SaveToSNSHistogramNexus.h        | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SaveVTK.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SetBeam.h     | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/SetSample.h   | 5 +----
 .../DataHandling/inc/MantidDataHandling/SetSampleMaterial.h | 5 +----
 .../DataHandling/inc/MantidDataHandling/SetScalingPSD.h     | 5 +----
 .../inc/MantidDataHandling/SortTableWorkspace.h             | 5 +----
 .../StartAndEndTimeFromNexusFileExtractor.h                 | 5 +----
 .../inc/MantidDataHandling/UpdateInstrumentFromFile.h       | 5 +----
 Framework/DataHandling/inc/MantidDataHandling/XmlHandler.h  | 5 +----
 Framework/DataHandling/src/LoadRaw/isisraw.h                | 5 +----
 Framework/DataHandling/src/LoadRaw/isisraw2.h               | 5 +----
 Framework/DataHandling/src/LoadRaw/item_struct.h            | 5 +----
 Framework/DataHandling/src/LoadRaw/vms_convert.h            | 5 +----
 Framework/DataHandling/test/AppendGeometryToSNSNexusTest.h  | 5 +----
 Framework/DataHandling/test/CheckMantidVersionTest.h        | 5 +----
 Framework/DataHandling/test/CompressEventsTest.h            | 5 +----
 .../DataHandling/test/CreateChunkingFromInstrumentTest.h    | 5 +----
 .../DataHandling/test/CreatePolarizationEfficienciesTest.h  | 5 +----
 Framework/DataHandling/test/CreateSampleShapeTest.h         | 5 +----
 Framework/DataHandling/test/CreateSimulationWorkspaceTest.h | 6 ++----
 Framework/DataHandling/test/DataBlockCompositeTest.h        | 5 +----
 Framework/DataHandling/test/DataBlockGeneratorTest.h        | 6 ++----
 Framework/DataHandling/test/DataBlockTest.h                 | 5 +----
 Framework/DataHandling/test/DefineGaugeVolumeTest.h         | 5 +----
 Framework/DataHandling/test/DeleteTableRowsTest.h           | 5 +----
 Framework/DataHandling/test/DetermineChunkingTest.h         | 5 +----
 Framework/DataHandling/test/DownloadFileTest.h              | 5 +----
 Framework/DataHandling/test/DownloadInstrumentTest.h        | 5 +----
 Framework/DataHandling/test/EventWorkspaceCollectionTest.h  | 5 +----
 Framework/DataHandling/test/ExtractMonitorWorkspaceTest.h   | 5 +----
 .../DataHandling/test/ExtractPolarizationEfficienciesTest.h | 5 +----
 .../DataHandling/test/FilterEventsByLogValuePreNexusTest.h  | 5 +----
 Framework/DataHandling/test/FindDetectorsInShapeTest.h      | 5 +----
 Framework/DataHandling/test/FindDetectorsParTest.h          | 4 +---
 Framework/DataHandling/test/GenerateGroupingPowderTest.h    | 5 +----
 Framework/DataHandling/test/GroupDetectors2Test.h           | 5 +----
 Framework/DataHandling/test/GroupDetectorsTest.h            | 5 +----
 Framework/DataHandling/test/H5UtilTest.h                    | 5 +----
 Framework/DataHandling/test/ISISDataArchiveTest.h           | 5 +----
 Framework/DataHandling/test/InstrumentRayTracerTest.h       | 5 +----
 .../test/JoinISISPolarizationEfficienciesTest.h             | 5 +----
 Framework/DataHandling/test/LoadAscii2Test.h                | 5 +----
 Framework/DataHandling/test/LoadAsciiStlTest.h              | 5 +----
 Framework/DataHandling/test/LoadAsciiTest.h                 | 5 +----
 Framework/DataHandling/test/LoadBBYTest.h                   | 5 +----
 Framework/DataHandling/test/LoadBinaryStlTest.h             | 6 ++----
 Framework/DataHandling/test/LoadCalFileTest.h               | 5 +----
 Framework/DataHandling/test/LoadCanSAS1dTest.h              | 5 +----
 Framework/DataHandling/test/LoadDAETest.h                   | 5 +----
 Framework/DataHandling/test/LoadDaveGrpTest.h               | 5 +----
 Framework/DataHandling/test/LoadDetectorInfoTest.h          | 5 +----
 Framework/DataHandling/test/LoadDetectorsGroupingFileTest.h | 5 +----
 Framework/DataHandling/test/LoadDiffCalTest.h               | 5 +----
 Framework/DataHandling/test/LoadDspacemapTest.h             | 5 +----
 Framework/DataHandling/test/LoadEMUauTest.h                 | 5 +----
 Framework/DataHandling/test/LoadEmptyInstrumentTest.h       | 5 +----
 Framework/DataHandling/test/LoadEventNexusIndexSetupTest.h  | 5 +----
 Framework/DataHandling/test/LoadEventNexusTest.h            | 5 +----
 Framework/DataHandling/test/LoadEventPreNexus2Test.h        | 5 +----
 Framework/DataHandling/test/LoadFITSTest.h                  | 5 +----
 Framework/DataHandling/test/LoadFullprofResolutionTest.h    | 5 +----
 Framework/DataHandling/test/LoadGSASInstrumentFileTest.h    | 5 +----
 Framework/DataHandling/test/LoadGSSTest.h                   | 6 ++----
 Framework/DataHandling/test/LoadHFIRSANSTest.h              | 6 ++----
 Framework/DataHandling/test/LoadIDFFromNexusTest.h          | 5 +----
 Framework/DataHandling/test/LoadILLDiffractionTest.h        | 5 +----
 Framework/DataHandling/test/LoadILLIndirect2Test.h          | 5 +----
 .../DataHandling/test/LoadILLPolarizationFactorsTest.h      | 5 +----
 Framework/DataHandling/test/LoadILLReflectometryTest.h      | 5 +----
 Framework/DataHandling/test/LoadILLSANSTest.h               | 5 +----
 Framework/DataHandling/test/LoadILLTOF2Test.h               | 5 +----
 Framework/DataHandling/test/LoadILLTest.h                   | 5 +----
 Framework/DataHandling/test/LoadISISNexusTest.h             | 5 +----
 .../test/LoadISISPolarizationEfficienciesTest.h             | 5 +----
 Framework/DataHandling/test/LoadInstrumentFromNexusTest.h   | 5 +----
 Framework/DataHandling/test/LoadInstrumentFromRawTest.h     | 5 +----
 Framework/DataHandling/test/LoadInstrumentTest.h            | 5 +----
 Framework/DataHandling/test/LoadIsawDetCalTest.h            | 5 +----
 Framework/DataHandling/test/LoadLLBTest.h                   | 6 ++----
 Framework/DataHandling/test/LoadLogTest.h                   | 5 +----
 Framework/DataHandling/test/LoadMLZTest.h                   | 5 +----
 Framework/DataHandling/test/LoadMappingTableTest.h          | 6 ++----
 Framework/DataHandling/test/LoadMaskTest.h                  | 5 +----
 Framework/DataHandling/test/LoadMcStasNexusTest.h           | 6 ++----
 Framework/DataHandling/test/LoadMcStasTest.h                | 5 +----
 Framework/DataHandling/test/LoadMuonLogTest.h               | 6 ++----
 Framework/DataHandling/test/LoadMuonNexus1Test.h            | 5 +----
 Framework/DataHandling/test/LoadMuonNexus2Test.h            | 5 +----
 Framework/DataHandling/test/LoadMuonNexusTest.h             | 5 +----
 Framework/DataHandling/test/LoadNGEMTest.h                  | 5 +----
 Framework/DataHandling/test/LoadNXSPETest.h                 | 5 +----
 Framework/DataHandling/test/LoadNXcanSASTest.h              | 6 ++----
 Framework/DataHandling/test/LoadNexusLogsTest.h             | 5 +----
 Framework/DataHandling/test/LoadNexusMonitorsTest.h         | 5 +----
 Framework/DataHandling/test/LoadNexusProcessed2Test.h       | 5 +----
 Framework/DataHandling/test/LoadNexusProcessedTest.h        | 5 +----
 Framework/DataHandling/test/LoadNexusTest.h                 | 5 +----
 Framework/DataHandling/test/LoadPDFgetNFileTest.h           | 5 +----
 Framework/DataHandling/test/LoadPLNTest.h                   | 5 +----
 Framework/DataHandling/test/LoadPSIMuonBinTest.h            | 5 +----
 Framework/DataHandling/test/LoadParameterFileTest.h         | 5 +----
 Framework/DataHandling/test/LoadPreNexusMonitorsTest.h      | 5 +----
 Framework/DataHandling/test/LoadPreNexusTest.h              | 5 +----
 Framework/DataHandling/test/LoadQKKTest.h                   | 5 +----
 Framework/DataHandling/test/LoadRKHTest.h                   | 5 +----
 Framework/DataHandling/test/LoadRaw3Test.h                  | 5 +----
 Framework/DataHandling/test/LoadRawBin0Test.h               | 5 +----
 Framework/DataHandling/test/LoadRawSaveNxsLoadNxsTest.h     | 5 +----
 Framework/DataHandling/test/LoadRawSpectrum0Test.h          | 5 +----
 Framework/DataHandling/test/LoadSESANSTest.h                | 5 +----
 Framework/DataHandling/test/LoadSINQFocusTest.h             | 5 +----
 Framework/DataHandling/test/LoadSNSNexusTest.h              | 5 +----
 Framework/DataHandling/test/LoadSNSspecTest.h               | 5 +----
 Framework/DataHandling/test/LoadSPETest.h                   | 5 +----
 Framework/DataHandling/test/LoadSampleDetailsFromRawTest.h  | 5 +----
 Framework/DataHandling/test/LoadSampleEnvironmentTest.h     | 5 +----
 Framework/DataHandling/test/LoadSampleShapeTest.h           | 6 ++----
 Framework/DataHandling/test/LoadSassenaTest.h               | 5 +----
 Framework/DataHandling/test/LoadSaveAsciiTest.h             | 5 +----
 Framework/DataHandling/test/LoadSpecTest.h                  | 5 +----
 Framework/DataHandling/test/LoadSpice2dTest.h               | 6 ++----
 Framework/DataHandling/test/LoadSpiceAsciiTest.h            | 5 +----
 Framework/DataHandling/test/LoadSpiceXML2DDetTest.h         | 5 +----
 Framework/DataHandling/test/LoadStlTest.h                   | 6 ++----
 Framework/DataHandling/test/LoadSwansTest.h                 | 5 +----
 Framework/DataHandling/test/LoadTBLTest.h                   | 5 +----
 Framework/DataHandling/test/LoadTOFRawNexusTest.h           | 5 +----
 Framework/DataHandling/test/LoadTest.h                      | 5 +----
 Framework/DataHandling/test/MaskDetectorsInShapeTest.h      | 6 ++----
 Framework/DataHandling/test/MaskDetectorsTest.h             | 5 +----
 Framework/DataHandling/test/MaskSpectraTest.h               | 5 +----
 Framework/DataHandling/test/MeshFileIOTest.h                | 5 +----
 Framework/DataHandling/test/ModifyDetectorDotDatFileTest.h  | 5 +----
 Framework/DataHandling/test/MoveInstrumentComponentTest.h   | 5 +----
 Framework/DataHandling/test/NXcanSASTestHelper.h            | 6 ++----
 Framework/DataHandling/test/NexusTesterTest.h               | 5 +----
 Framework/DataHandling/test/ORNLDataArchiveTest.h           | 5 +----
 Framework/DataHandling/test/PDLoadCharacterizationsTest.h   | 5 +----
 Framework/DataHandling/test/PrecompiledHeader.h             | 5 +----
 Framework/DataHandling/test/RawFileInfoTest.h               | 5 +----
 Framework/DataHandling/test/RemoveLogsTest.h                | 5 +----
 Framework/DataHandling/test/RenameLogTest.h                 | 5 +----
 Framework/DataHandling/test/RotateInstrumentComponentTest.h | 5 +----
 Framework/DataHandling/test/RotateSourceTest.h              | 5 +----
 Framework/DataHandling/test/SampleEnvironmentFactoryTest.h  | 5 +----
 .../DataHandling/test/SampleEnvironmentSpecFileFinderTest.h | 5 +----
 .../DataHandling/test/SampleEnvironmentSpecParserTest.h     | 5 +----
 Framework/DataHandling/test/SampleEnvironmentSpecTest.h     | 5 +----
 Framework/DataHandling/test/SaveANSTOAsciiTest.h            | 5 +----
 Framework/DataHandling/test/SaveAscii2Test.h                | 6 ++----
 Framework/DataHandling/test/SaveAsciiTest.h                 | 5 +----
 Framework/DataHandling/test/SaveBankScatteringAnglesTest.h  | 5 +----
 Framework/DataHandling/test/SaveCSVTest.h                   | 5 +----
 Framework/DataHandling/test/SaveCalFileTest.h               | 5 +----
 Framework/DataHandling/test/SaveCanSAS1dTest.h              | 5 +----
 Framework/DataHandling/test/SaveCanSAS1dTest2.h             | 5 +----
 Framework/DataHandling/test/SaveDaveGrpTest.h               | 5 +----
 Framework/DataHandling/test/SaveDetectorsGroupingTest.h     | 5 +----
 Framework/DataHandling/test/SaveDiffCalTest.h               | 5 +----
 Framework/DataHandling/test/SaveDspacemapTest.h             | 5 +----
 Framework/DataHandling/test/SaveFITSTest.h                  | 5 +----
 Framework/DataHandling/test/SaveFocusedXYETest.h            | 5 +----
 Framework/DataHandling/test/SaveFullprofResolutionTest.h    | 5 +----
 Framework/DataHandling/test/SaveGDATest.h                   | 5 +----
 Framework/DataHandling/test/SaveGSASInstrumentFileTest.h    | 5 +----
 Framework/DataHandling/test/SaveGSSTest.h                   | 5 +----
 Framework/DataHandling/test/SaveILLCosmosAsciiTest.h        | 6 ++----
 Framework/DataHandling/test/SaveIsawDetCalTest.h            | 5 +----
 Framework/DataHandling/test/SaveMaskTest.h                  | 5 +----
 Framework/DataHandling/test/SaveNISTDATTest.h               | 5 +----
 Framework/DataHandling/test/SaveNXSPETest.h                 | 5 +----
 Framework/DataHandling/test/SaveNXTomoTest.h                | 5 +----
 Framework/DataHandling/test/SaveNXcanSASTest.h              | 5 +----
 Framework/DataHandling/test/SaveNexusESSTest.h              | 5 +----
 Framework/DataHandling/test/SaveNexusGeometryTest.h         | 5 +----
 Framework/DataHandling/test/SaveNexusProcessedTest.h        | 6 ++----
 Framework/DataHandling/test/SaveNexusTest.h                 | 6 ++----
 Framework/DataHandling/test/SaveOpenGenieAsciiTest.h        | 5 +----
 Framework/DataHandling/test/SavePARTest.h                   | 5 +----
 Framework/DataHandling/test/SavePDFGuiTest.h                | 5 +----
 Framework/DataHandling/test/SavePHXTest.h                   | 5 +----
 Framework/DataHandling/test/SaveParameterFileTest.h         | 5 +----
 Framework/DataHandling/test/SaveRKHTest.h                   | 5 +----
 Framework/DataHandling/test/SaveRMCProfileTest.h            | 5 +----
 Framework/DataHandling/test/SaveReflCustomAsciiTest.h       | 6 ++----
 Framework/DataHandling/test/SaveReflThreeColumnAsciiTest.h  | 5 +----
 Framework/DataHandling/test/SaveReflectometryAsciiTest.h    | 6 ++----
 Framework/DataHandling/test/SaveSESANSTest.h                | 5 +----
 Framework/DataHandling/test/SaveSPETest.h                   | 5 +----
 Framework/DataHandling/test/SaveStlTest.h                   | 6 ++----
 Framework/DataHandling/test/SaveTBLTest.h                   | 6 ++----
 Framework/DataHandling/test/SaveToSNSHistogramNexusTest.h   | 6 ++----
 Framework/DataHandling/test/SetBeamTest.h                   | 5 +----
 Framework/DataHandling/test/SetSampleMaterialTest.h         | 5 +----
 Framework/DataHandling/test/SetSampleTest.h                 | 5 +----
 Framework/DataHandling/test/SetScalingPSDTest.h             | 5 +----
 Framework/DataHandling/test/SortTableWorkspaceTest.h        | 5 +----
 .../test/StartAndEndTimeFromNexusFileExtractorTest.h        | 5 +----
 Framework/DataHandling/test/UpdateInstrumentFromFileTest.h  | 5 +----
 Framework/DataHandling/test/XMLInstrumentParameterTest.h    | 5 +----
 395 files changed, 441 insertions(+), 1579 deletions(-)

diff --git a/Framework/DataHandling/inc/MantidDataHandling/AppendGeometryToSNSNexus.h b/Framework/DataHandling/inc/MantidDataHandling/AppendGeometryToSNSNexus.h
index 515f95fa7d4..03137f7dc1b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/AppendGeometryToSNSNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/AppendGeometryToSNSNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_APPENDGEOMETRYTOSNSNEXUS_H_
-#define MANTID_DATAHANDLING_APPENDGEOMETRYTOSNSNEXUS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -73,5 +72,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_APPENDGEOMETRYTOSNSNEXUS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/AsciiPointBase.h b/Framework/DataHandling/inc/MantidDataHandling/AsciiPointBase.h
index 6aaca0aa0d3..75ce0a26f85 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/AsciiPointBase.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/AsciiPointBase.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ASCIIPOINTBASE_H_
-#define MANTID_DATAHANDLING_ASCIIPOINTBASE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -63,5 +62,3 @@ protected:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_ASCIIPOINTBASE_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/BankPulseTimes.h b/Framework/DataHandling/inc/MantidDataHandling/BankPulseTimes.h
index 6d03a0ab0ab..6eb0d54646b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/BankPulseTimes.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/BankPulseTimes.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_KERNEL_BANKPULSETIMES_H
-#define MANTID_KERNEL_BANKPULSETIMES_H
+#pragma once
 
 #include "MantidKernel/DateAndTime.h"
 #include "MantidKernel/Property.h"
@@ -47,5 +46,3 @@ public:
   /// Vector of period numbers corresponding to each pulse
   std::vector<int> periodNumbers;
 };
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/CheckMantidVersion.h b/Framework/DataHandling/inc/MantidDataHandling/CheckMantidVersion.h
index 7bd094cfec2..d4c2a2ff43a 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/CheckMantidVersion.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/CheckMantidVersion.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CHECKMANTIDVERSION_H_
-#define MANTID_DATAHANDLING_CHECKMANTIDVERSION_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -39,5 +38,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_CHECKMANTIDVERSION_H_ */
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/CompressEvents.h b/Framework/DataHandling/inc/MantidDataHandling/CompressEvents.h
index 3a97b9aabc3..dd91de04688 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/CompressEvents.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/CompressEvents.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_COMPRESSEVENTS_H_
-#define MANTID_DATAHANDLING_COMPRESSEVENTS_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 
@@ -52,5 +51,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_COMPRESSEVENTS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/CreateChunkingFromInstrument.h b/Framework/DataHandling/inc/MantidDataHandling/CreateChunkingFromInstrument.h
index 2f16b50836c..46a685dd613 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/CreateChunkingFromInstrument.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/CreateChunkingFromInstrument.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CREATECHUNKINGFROMINSTRUMENT_H_
-#define MANTID_DATAHANDLING_CREATECHUNKINGFROMINSTRUMENT_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidGeometry/Instrument.h"
@@ -32,5 +31,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_CREATECHUNKINGFROMINSTRUMENT_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/CreatePolarizationEfficiencies.h b/Framework/DataHandling/inc/MantidDataHandling/CreatePolarizationEfficiencies.h
index dd11ed77459..6a43da046e1 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/CreatePolarizationEfficiencies.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/CreatePolarizationEfficiencies.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CREATEPOLARIZATIONEFFICIENCIES_H_
-#define MANTID_DATAHANDLING_CREATEPOLARIZATIONEFFICIENCIES_H_
+#pragma once
 
 #include "MantidDataHandling/CreatePolarizationEfficienciesBase.h"
 #include "MantidKernel/System.h"
@@ -31,5 +30,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_CREATEPOLARIZATIONEFFICIENCIES_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/CreatePolarizationEfficienciesBase.h b/Framework/DataHandling/inc/MantidDataHandling/CreatePolarizationEfficienciesBase.h
index ace298ff461..b6883f778d4 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/CreatePolarizationEfficienciesBase.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/CreatePolarizationEfficienciesBase.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CREATEPOLARIZATIONEFFICIENCIESBASE_H_
-#define MANTID_DATAHANDLING_CREATEPOLARIZATIONEFFICIENCIESBASE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -52,5 +51,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_CREATEPOLARIZATIONEFFICIENCIESBASE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/CreateSampleShape.h b/Framework/DataHandling/inc/MantidDataHandling/CreateSampleShape.h
index 74893dc8382..881f3232de8 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/CreateSampleShape.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/CreateSampleShape.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CREATESAMPLESHAPE_H_
-#define MANTID_DATAHANDLING_CREATESAMPLESHAPE_H_
+#pragma once
 
 //--------------------------------
 // Includes
@@ -51,5 +50,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_CREATESAMPLESHAPE_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/CreateSimulationWorkspace.h b/Framework/DataHandling/inc/MantidDataHandling/CreateSimulationWorkspace.h
index c0af7a755d0..642f04f376b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/CreateSimulationWorkspace.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/CreateSimulationWorkspace.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CREATESIMULATIONWORKSPACE_H_
-#define MANTID_DATAHANDLING_CREATESIMULATIONWORKSPACE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidGeometry/Instrument.h"
@@ -69,5 +68,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_CREATESIMULATIONWORKSPACE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DataBlock.h b/Framework/DataHandling/inc/MantidDataHandling/DataBlock.h
index 7e542f3f4c5..040a1da942f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DataBlock.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DataBlock.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DATABLOCK_H_
-#define MANTID_DATAHANDLING_DATABLOCK_H_
+#pragma once
 
 #include "MantidDataHandling/DllConfig.h"
 #include "MantidNexus/NexusClasses.h"
@@ -59,5 +58,3 @@ protected:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_DATABLOCK_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DataBlockComposite.h b/Framework/DataHandling/inc/MantidDataHandling/DataBlockComposite.h
index 5e9a5b01241..b519ddaddbb 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DataBlockComposite.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DataBlockComposite.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DATABLOCK_COMPOSITE_H_
-#define MANTID_DATAHANDLING_DATABLOCK_COMPOSITE_H_
+#pragma once
 
 #include "MantidDataHandling/DataBlock.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -149,5 +148,4 @@ void DLLExport populateDataBlockCompositeWithContainer(
   }
 }
 } // namespace DataHandling
-} // namespace Mantid
-#endif
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DataBlockGenerator.h b/Framework/DataHandling/inc/MantidDataHandling/DataBlockGenerator.h
index 132a1f918a4..ce3122546dc 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DataBlockGenerator.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DataBlockGenerator.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DATABLOCKGENERATOR_H_
-#define MANTID_DATAHANDLING_DATABLOCKGENERATOR_H_
+#pragma once
 
 #include "MantidDataHandling/DllConfig.h"
 #include <boost/optional.hpp>
@@ -40,5 +39,3 @@ public:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DefaultEventLoader.h b/Framework/DataHandling/inc/MantidDataHandling/DefaultEventLoader.h
index 6385fd299fb..f5b4bd0a5c5 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DefaultEventLoader.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DefaultEventLoader.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DEFAULTEVENTLOADER_H_
-#define MANTID_DATAHANDLING_DEFAULTEVENTLOADER_H_
+#pragma once
 
 #include "MantidAPI/Axis.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -151,5 +150,3 @@ void DefaultEventLoader::makeMapToEventLists(
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_DEFAULTEVENTLOADER_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DefineGaugeVolume.h b/Framework/DataHandling/inc/MantidDataHandling/DefineGaugeVolume.h
index d2d0698f36a..e55330eaa48 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DefineGaugeVolume.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DefineGaugeVolume.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DEFINEGAUGEVOLUME_H_
-#define MANTID_DATAHANDLING_DEFINEGAUGEVOLUME_H_
+#pragma once
 
 //--------------------------------
 // Includes
@@ -49,5 +48,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_DEFINEGAUGEVOLUME_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DeleteTableRows.h b/Framework/DataHandling/inc/MantidDataHandling/DeleteTableRows.h
index b432cec292f..121cfbd0874 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DeleteTableRows.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DeleteTableRows.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DELETETABLEROWS_H_
-#define MANTID_DATAHANDLING_DELETETABLEROWS_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -49,5 +48,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_DELETETABLEROWS_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DetermineChunking.h b/Framework/DataHandling/inc/MantidDataHandling/DetermineChunking.h
index 92a00eab1d4..0d7cfce5216 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DetermineChunking.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DetermineChunking.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DetermineChunking_H_
-#define MANTID_DATAHANDLING_DetermineChunking_H_
+#pragma once
 
 #include "MantidAPI/IEventWorkspace_fwd.h"
 #include "MantidAPI/ParallelAlgorithm.h"
@@ -64,5 +63,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_DetermineChunking_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DllConfig.h b/Framework/DataHandling/inc/MantidDataHandling/DllConfig.h
index 7916244b498..e3baae7154b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DllConfig.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DllConfig.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DLLCONFIG_H_
-#define MANTID_DATAHANDLING_DLLCONFIG_H_
+#pragma once
 
 /*
     This file contains the DLLExport/DLLImport linkage configuration for the
@@ -20,5 +19,3 @@
 #else
 #define MANTID_DATAHANDLING_DLL DLLImport
 #endif /* IN_MANTID_DATAHANDLING*/
-
-#endif // MANTID_DATAHANDLING_DLLCONFIG_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DownloadFile.h b/Framework/DataHandling/inc/MantidDataHandling/DownloadFile.h
index c50b1014e2b..d0cd55b2c89 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DownloadFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DownloadFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DOWNLOADFILE_H_
-#define MANTID_DATAHANDLING_DOWNLOADFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -44,5 +43,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_DOWNLOADFILE_H_ */
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/DownloadInstrument.h b/Framework/DataHandling/inc/MantidDataHandling/DownloadInstrument.h
index 85b820ba475..ec00f4cee4d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/DownloadInstrument.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/DownloadInstrument.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DOWNLOADINSTRUMENT_H_
-#define MANTID_DATAHANDLING_DOWNLOADINSTRUMENT_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/ProxyInfo.h"
@@ -58,5 +57,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_DOWNLOADINSTRUMENT_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/EventWorkspaceCollection.h b/Framework/DataHandling/inc/MantidDataHandling/EventWorkspaceCollection.h
index 41aab046801..92b67220c4f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/EventWorkspaceCollection.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/EventWorkspaceCollection.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_EventWorkspaceCollection_H_
-#define MANTID_DATAHANDLING_EventWorkspaceCollection_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace.h"
 #include "MantidAPI/WorkspaceGroup.h"
@@ -100,5 +99,3 @@ using EventWorkspaceCollection_uptr = std::unique_ptr<EventWorkspaceCollection>;
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_EventWorkspaceCollection_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ExtractMonitorWorkspace.h b/Framework/DataHandling/inc/MantidDataHandling/ExtractMonitorWorkspace.h
index 22067db2e48..45be425670b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ExtractMonitorWorkspace.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ExtractMonitorWorkspace.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_EXTRACTMONITORWORKSPACE_H_
-#define MANTID_DATAHANDLING_EXTRACTMONITORWORKSPACE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -34,5 +33,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_EXTRACTMONITORWORKSPACE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ExtractPolarizationEfficiencies.h b/Framework/DataHandling/inc/MantidDataHandling/ExtractPolarizationEfficiencies.h
index 3e3a429a697..adf43574345 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ExtractPolarizationEfficiencies.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ExtractPolarizationEfficiencies.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_EXTRACTPOLARIZATIONEFFICIENCIES_H_
-#define MANTID_DATAHANDLING_EXTRACTPOLARIZATIONEFFICIENCIES_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -33,5 +32,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_EXTRACTPOLARIZATIONEFFICIENCIES_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/FilterEventsByLogValuePreNexus.h b/Framework/DataHandling/inc/MantidDataHandling/FilterEventsByLogValuePreNexus.h
index 4c768be59cf..41fbcf8f234 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/FilterEventsByLogValuePreNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/FilterEventsByLogValuePreNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef FILTEREVENTSBYLOGVALUEPRENEXUS_H_
-#define FILTEREVENTSBYLOGVALUEPRENEXUS_H_
+#pragma once
 
 #include "MantidAPI/DeprecatedAlgorithm.h"
 #include "MantidAPI/IFileLoader.h"
@@ -272,5 +271,4 @@ private:
   bool m_corretctTOF;
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif /*FILTEREVENTSBYLOGVALUEPRENEXUS_H_*/
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/FindDetectorsInShape.h b/Framework/DataHandling/inc/MantidDataHandling/FindDetectorsInShape.h
index 5eeb79339d9..6f35c0a4326 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/FindDetectorsInShape.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/FindDetectorsInShape.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_FINDDETECTORSINSHAPE_H_
-#define MANTID_DATAHANDLING_FINDDETECTORSINSHAPE_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 
@@ -63,5 +62,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_FINDDETECTORSINSHAPE_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/FindDetectorsPar.h b/Framework/DataHandling/inc/MantidDataHandling/FindDetectorsPar.h
index 0850a24058d..363f92ca3d7 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/FindDetectorsPar.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/FindDetectorsPar.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDLING_FIND_DETPAR_H_
-#define DATAHANDLING_FIND_DETPAR_H_
+#pragma once
 
 #include <float.h>
 #include <fstream>
@@ -258,5 +257,3 @@ public:
 
 } // end namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/GenerateGroupingPowder.h b/Framework/DataHandling/inc/MantidDataHandling/GenerateGroupingPowder.h
index bf9d94676eb..68e99c7a732 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/GenerateGroupingPowder.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/GenerateGroupingPowder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_GENERATEGROUPINGPOWDER_H_
-#define MANTID_DATAHANDLING_GENERATEGROUPINGPOWDER_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -39,5 +38,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_GENERATEGROUPINGPOWDER_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/GroupDetectors.h b/Framework/DataHandling/inc/MantidDataHandling/GroupDetectors.h
index 1c0cd9ff902..7504062a189 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/GroupDetectors.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/GroupDetectors.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_GROUPDETECTORS_H_
-#define MANTID_DATAHANDLING_GROUPDETECTORS_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -69,5 +68,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_GROUPDETECTORS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/GroupDetectors2.h b/Framework/DataHandling/inc/MantidDataHandling/GroupDetectors2.h
index 9f5dcbb1e91..6ed7cacd3bb 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/GroupDetectors2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/GroupDetectors2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_GROUPDETECTORS2_H_
-#define MANTID_DATAHANDLING_GROUPDETECTORS2_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataObjects/EventWorkspace.h"
@@ -282,5 +281,3 @@ void GroupDetectors2::moveOthers(const std::set<int64_t> &unGroupedSet,
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_GROUPDETECTORS2_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/H5Util.h b/Framework/DataHandling/inc/MantidDataHandling/H5Util.h
index 8c5d5e0da62..3bec8788dd1 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/H5Util.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/H5Util.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_H5UTIL_H_
-#define MANTID_DATAHANDLING_H5UTIL_H_
+#pragma once
 
 #include "MantidDataHandling/DllConfig.h"
 
@@ -122,5 +121,3 @@ std::vector<NumT> readArray1DCoerce(H5::DataSet &dataset);
 } // namespace H5Util
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_H5UTIL_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ISISDataArchive.h b/Framework/DataHandling/inc/MantidDataHandling/ISISDataArchive.h
index f2f61365f27..e2a089021e3 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ISISDataArchive.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ISISDataArchive.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ISISDATAARCHIVE_H_
-#define MANTID_DATAHANDLING_ISISDATAARCHIVE_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -45,5 +44,3 @@ protected:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_ISISDATAARCHIVE_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ISISRunLogs.h b/Framework/DataHandling/inc/MantidDataHandling/ISISRunLogs.h
index 032ae6c4349..4281af62a6d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ISISRunLogs.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ISISRunLogs.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ISISRUNLOGS_H_
-#define MANTID_DATAHANDLING_ISISRUNLOGS_H_
+#pragma once
 
 #include "MantidKernel/LogParser.h"
 #include "MantidKernel/System.h"
@@ -45,5 +44,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_ISISRUNLOGS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/JoinISISPolarizationEfficiencies.h b/Framework/DataHandling/inc/MantidDataHandling/JoinISISPolarizationEfficiencies.h
index b51b291787e..f2bbf256eff 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/JoinISISPolarizationEfficiencies.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/JoinISISPolarizationEfficiencies.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_JOINISISPOLARIZATIONEFFICIENCIES_H_
-#define MANTID_DATAHANDLING_JOINISISPOLARIZATIONEFFICIENCIES_H_
+#pragma once
 
 #include "MantidDataHandling/CreatePolarizationEfficienciesBase.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -43,5 +42,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_JOINISISPOLARIZATIONEFFICIENCIES_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/Load.h b/Framework/DataHandling/inc/MantidDataHandling/Load.h
index 231f51d5ca8..a4ee231daa3 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/Load.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/Load.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOAD_H_
-#define MANTID_DATAHANDLING_LOAD_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/WorkspaceGroup_fwd.h"
@@ -107,5 +106,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_LOAD_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadANSTOEventFile.h b/Framework/DataHandling/inc/MantidDataHandling/LoadANSTOEventFile.h
index ca3dc7e0ec0..5db6a29512b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadANSTOEventFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadANSTOEventFile.h
@@ -1,5 +1,4 @@
-#ifndef DATAHANDING_ANSTOEVENTFILE_H_
-#define DATAHANDING_ANSTOEVENTFILE_H_
+#pragma once
 
 #include <cstdio>
 #include <stdexcept>
@@ -358,5 +357,3 @@ void ReadEventFile(IReader &loader, IEventHandler &handler, IProgress &progress,
 } // namespace ANSTO
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // DATAHANDING_ANSTOEVENTFILE_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadANSTOHelper.h b/Framework/DataHandling/inc/MantidDataHandling/LoadANSTOHelper.h
index 23e549868b0..34e41fd3a2e 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadANSTOHelper.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadANSTOHelper.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_ANSTO_H_
-#define DATAHANDING_ANSTO_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -266,5 +265,3 @@ public:
 } // namespace ANSTO
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // DATAHANDING_ANSTO_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadAscii.h b/Framework/DataHandling/inc/MantidDataHandling/LoadAscii.h
index f3c9c58869e..2a0ff98847c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADASCII_H_
-#define MANTID_DATAHANDLING_LOADASCII_H_
+#pragma once
 
 #include "MantidAPI/DeprecatedAlgorithm.h"
 #include "MantidAPI/IFileLoader.h"
@@ -82,5 +81,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_LOADASCII_H_  */
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadAscii2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadAscii2.h
index df4771a4f6a..71b19ea45c7 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadAscii2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadAscii2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LoadAscii2_H_
-#define MANTID_DATAHANDLING_LoadAscii2_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -114,5 +113,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_LoadAscii2_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadAsciiStl.h b/Framework/DataHandling/inc/MantidDataHandling/LoadAsciiStl.h
index 214527a9ce2..9799919e6de 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadAsciiStl.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadAsciiStl.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADASCIISTL_H_
-#define MANTID_DATAHANDLING_LOADASCIISTL_H_
+#pragma once
 #include "MantidDataHandling/LoadStl.h"
 #include <iosfwd>
 namespace Mantid {
@@ -38,5 +37,4 @@ private:
 };
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif /* MANTID_DATAHANDLING_LOADASCIISTL_H_ */
\ No newline at end of file
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadBBY.h b/Framework/DataHandling/inc/MantidDataHandling/LoadBBY.h
index 3319ee3e59a..8a5ddcacf08 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadBBY.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadBBY.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_LOADBBY_H_
-#define DATAHANDING_LOADBBY_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -96,5 +95,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // DATAHANDING_LOADBBY_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadBankFromDiskTask.h b/Framework/DataHandling/inc/MantidDataHandling/LoadBankFromDiskTask.h
index 0faae2d5f90..20394ae5f90 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadBankFromDiskTask.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadBankFromDiskTask.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADBANKFROMDISKTASK_H_
-#define MANTID_DATAHANDLING_LOADBANKFROMDISKTASK_H_
+#pragma once
 
 #include "MantidAPI/Progress.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -80,5 +79,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADBANKFROMDISKTASK_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadBinaryStl.h b/Framework/DataHandling/inc/MantidDataHandling/LoadBinaryStl.h
index dca31766a2b..885a37edf73 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadBinaryStl.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadBinaryStl.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADBINARYSTL_H_
-#define MANTID_DATAHANDLING_LOADBINARYSTL_H_
+#pragma once
 #include "MantidDataHandling/LoadStl.h"
 
 namespace Mantid {
@@ -37,5 +36,4 @@ private:
 };
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif /* MANTID_DATAHANDLING_LOADBINARYSTL_H_ */
\ No newline at end of file
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadCalFile.h b/Framework/DataHandling/inc/MantidDataHandling/LoadCalFile.h
index 6946b50cdc3..f6d120b7d2c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadCalFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadCalFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADCALFILE_H_
-#define MANTID_DATAHANDLING_LOADCALFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/IAlgorithm.h"
@@ -77,5 +76,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADCALFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadCanSAS1D.h b/Framework/DataHandling/inc/MantidDataHandling/LoadCanSAS1D.h
index 42f03728fd5..4e2c787aa22 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadCanSAS1D.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadCanSAS1D.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LoadCanSAS1D_H
-#define MANTID_DATAHANDLING_LoadCanSAS1D_H
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidAPI/WorkspaceGroup_fwd.h"
@@ -90,5 +89,3 @@ protected:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadCanSAS1D2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadCanSAS1D2.h
index 78055b88b19..ae61a75f103 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadCanSAS1D2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadCanSAS1D2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LoadCanSAS1D2_H
-#define MANTID_DATAHANDLING_LoadCanSAS1D2_H
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -82,5 +81,4 @@ private:
                            const std::string &output_name);
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif // MANTID_DATAHANDLING_LoadCanSAS1D2_H
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadDaveGrp.h b/Framework/DataHandling/inc/MantidDataHandling/LoadDaveGrp.h
index c4aeee6ccab..e10d459b107 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadDaveGrp.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadDaveGrp.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADDAVEGRP_H_
-#define MANTID_DATAHANDLING_LOADDAVEGRP_H_
+#pragma once
 
 #include <fstream>
 #include <string>
@@ -149,5 +148,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_LOADDAVEGRP_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadDetectorInfo.h b/Framework/DataHandling/inc/MantidDataHandling/LoadDetectorInfo.h
index 2512cf9a095..be5c952181f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadDetectorInfo.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadDetectorInfo.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADDETECTORINFO_H_
-#define MANTID_DATAHANDLING_LOADDETECTORINFO_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidGeometry/Instrument.h"
@@ -89,5 +88,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADDETECTORINFO_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadDetectorsGroupingFile.h b/Framework/DataHandling/inc/MantidDataHandling/LoadDetectorsGroupingFile.h
index 4aebb341456..88bcf39e502 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadDetectorsGroupingFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadDetectorsGroupingFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADDETECTORSGROUPINGFILE_H_
-#define MANTID_DATAHANDLING_LOADDETECTORSGROUPINGFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataObjects/GroupingWorkspace.h"
@@ -219,5 +218,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADDETECTORSGROUPINGFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadDiffCal.h b/Framework/DataHandling/inc/MantidDataHandling/LoadDiffCal.h
index 18f9a246d28..1384ea42864 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadDiffCal.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadDiffCal.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADDIFFCAL_H_
-#define MANTID_DATAHANDLING_LOADDIFFCAL_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidGeometry/Instrument.h"
@@ -61,5 +60,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADDIFFCAL_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadDspacemap.h b/Framework/DataHandling/inc/MantidDataHandling/LoadDspacemap.h
index 206e1c54393..63f73c07997 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadDspacemap.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadDspacemap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADDSPACEMAP_H_
-#define MANTID_DATAHANDLING_LOADDSPACEMAP_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -59,5 +58,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADDSPACEMAP_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadEMU.h b/Framework/DataHandling/inc/MantidDataHandling/LoadEMU.h
index d74c777d737..ac4d4e56124 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadEMU.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadEMU.h
@@ -1,5 +1,4 @@
-#ifndef DATAHANDING_LOADEMU_H_
-#define DATAHANDING_LOADEMU_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -187,5 +186,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // DATAHANDING_LOADEMU_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadEmptyInstrument.h b/Framework/DataHandling/inc/MantidDataHandling/LoadEmptyInstrument.h
index a1d234e51de..87483d94a9f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadEmptyInstrument.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadEmptyInstrument.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADEMPTYINSTRUMENT_H_
-#define MANTID_DATAHANDLING_LOADEMPTYINSTRUMENT_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -79,5 +78,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADEMPTYINSTRUMENT_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadEventNexus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadEventNexus.h
index 502500ffdf9..b75c9dd5cda 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadEventNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadEventNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADEVENTNEXUS_H_
-#define MANTID_DATAHANDLING_LOADEVENTNEXUS_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidAPI/WorkspaceGroup.h"
@@ -803,5 +802,3 @@ bool LoadEventNexus::runLoadIDFFromNexus(const std::string &nexusfilename,
 }
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADEVENTNEXUS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadEventNexusIndexSetup.h b/Framework/DataHandling/inc/MantidDataHandling/LoadEventNexusIndexSetup.h
index d732e8f5b89..c2cc435cc9c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadEventNexusIndexSetup.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadEventNexusIndexSetup.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADEVENTNEXUSINDEXSETUP_H_
-#define MANTID_DATAHANDLING_LOADEVENTNEXUSINDEXSETUP_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -53,5 +52,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADEVENTNEXUSINDEXSETUP_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadEventPreNexus2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadEventPreNexus2.h
index 81c1f80a309..cb7adfda124 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadEventPreNexus2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadEventPreNexus2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADEVENTPRENEXUS_H_
-#define LOADEVENTPRENEXUS_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataObjects/EventWorkspace.h"
@@ -218,5 +217,4 @@ private:
   void processInvestigationInputs();
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif /*LOADEVENTPRENEXUS_H_*/
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadFITS.h b/Framework/DataHandling/inc/MantidDataHandling/LoadFITS.h
index 26de9f2ae30..a185b4b5c6c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadFITS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadFITS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADFITS_H_
-#define MANTID_DATAHANDLING_LOADFITS_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -181,5 +180,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_LOADFITS_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadFullprofResolution.h b/Framework/DataHandling/inc/MantidDataHandling/LoadFullprofResolution.h
index 922c10ed71f..682472a00f9 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadFullprofResolution.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadFullprofResolution.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADFULLPROFRESOLUTION_H_
-#define MANTID_DATAHANDLING_LOADFULLPROFRESOLUTION_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataObjects/TableWorkspace.h"
@@ -161,5 +160,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADFULLPROFRESOLUTION_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadGSASInstrumentFile.h b/Framework/DataHandling/inc/MantidDataHandling/LoadGSASInstrumentFile.h
index 52a72709400..432086914e8 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadGSASInstrumentFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadGSASInstrumentFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADGSASINSTRUMENTFILE_H_
-#define MANTID_DATAHANDLING_LOADGSASINSTRUMENTFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataObjects/TableWorkspace.h"
@@ -79,5 +78,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADGSASINSTRUMENTFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadGSS.h b/Framework/DataHandling/inc/MantidDataHandling/LoadGSS.h
index dbda2cf879c..8a357fc09ec 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadGSS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadGSS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_LOADGSS_H_
-#define DATAHANDING_LOADGSS_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -71,5 +70,4 @@ private:
                                 const std::vector<double> &twothetas);
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif // DATAHANDING_LOADGSS_H_
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadGeometry.h b/Framework/DataHandling/inc/MantidDataHandling/LoadGeometry.h
index 1b75e144a39..f1af430b305 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadGeometry.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadGeometry.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADGEOMETRY_H_
-#define MANTID_DATAHANDLING_LOADGEOMETRY_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -31,5 +30,3 @@ const std::vector<std::string> validExtensions();
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADGEOMETRY_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadHFIRSANS.h b/Framework/DataHandling/inc/MantidDataHandling/LoadHFIRSANS.h
index 66c8f277717..d13111d5726 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadHFIRSANS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadHFIRSANS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LoadHFIRSANS_H
-#define MANTID_DATAHANDLING_LoadHFIRSANS_H
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/XmlHandler.h"
@@ -136,5 +135,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadHelper.h b/Framework/DataHandling/inc/MantidDataHandling/LoadHelper.h
index cd70a124b2d..f21a7fcafe3 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadHelper.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadHelper.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LoadHelper_H_
-#define MANTID_DATAHANDLING_LoadHelper_H_
+#pragma once
 
 #include "MantidAPI/Run.h"
 #include "MantidKernel/System.h"
@@ -58,5 +57,3 @@ private:
 } // namespace DataHandling
 // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LoadHelper_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadIDFFromNexus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadIDFFromNexus.h
index db7cf61b2e5..d950f220624 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadIDFFromNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadIDFFromNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADIDFFROMNEXUS_H_
-#define MANTID_DATAHANDLING_LOADIDFFROMNEXUS_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -83,5 +82,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADIDFFROMNEXUS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadILLDiffraction.h b/Framework/DataHandling/inc/MantidDataHandling/LoadILLDiffraction.h
index 92ac1a46db2..d24ba3fe0d2 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadILLDiffraction.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadILLDiffraction.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLDIFFRACTION_H_
-#define MANTID_DATAHANDLING_LOADILLDIFFRACTION_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -119,5 +118,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADILLDIFFRACTION_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadILLIndirect2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadILLIndirect2.h
index d340ac4a14d..691c3ede883 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadILLIndirect2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadILLIndirect2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLINDIRECT2_H_
-#define MANTID_DATAHANDLING_LOADILLINDIRECT2_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/LoadHelper.h"
@@ -70,5 +69,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADILLINDIRECT2_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadILLPolarizationFactors.h b/Framework/DataHandling/inc/MantidDataHandling/LoadILLPolarizationFactors.h
index 93a4e840bc8..12627afee13 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadILLPolarizationFactors.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadILLPolarizationFactors.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLPOLARIZATIONFACTORS_H_
-#define MANTID_DATAHANDLING_LOADILLPOLARIZATIONFACTORS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -32,5 +31,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADILLPOLARIZATIONFACTORS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadILLReflectometry.h b/Framework/DataHandling/inc/MantidDataHandling/LoadILLReflectometry.h
index a44fcb11fe0..cc4377ee766 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadILLReflectometry.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadILLReflectometry.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLREFLECTOMETRY_H_
-#define MANTID_DATAHANDLING_LOADILLREFLECTOMETRY_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -99,5 +98,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADILLREFLECTOMETRY_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadILLSANS.h b/Framework/DataHandling/inc/MantidDataHandling/LoadILLSANS.h
index 5c36237d2c3..f057580f863 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadILLSANS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadILLSANS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLSANS_H_
-#define MANTID_DATAHANDLING_LOADILLSANS_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/LoadHelper.h"
@@ -101,5 +100,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADILLSANS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadILLTOF2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadILLTOF2.h
index e0ed8454cf3..5988e8116e7 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadILLTOF2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadILLTOF2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLTOF2_H_
-#define MANTID_DATAHANDLING_LOADILLTOF2_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/LoadHelper.h"
@@ -91,5 +90,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADILLTOF2_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadISISNexus2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadISISNexus2.h
index a57f42863c5..1843942ec66 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadISISNexus2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadISISNexus2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LoadISISNexus22_H_
-#define MANTID_DATAHANDLING_LoadISISNexus22_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -211,5 +210,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LoadISISNexus2_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadISISPolarizationEfficiencies.h b/Framework/DataHandling/inc/MantidDataHandling/LoadISISPolarizationEfficiencies.h
index 1a50994c9bf..588aa7bb6ca 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadISISPolarizationEfficiencies.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadISISPolarizationEfficiencies.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADISISPOLARIZATIONEFFICIENCIES_H_
-#define MANTID_DATAHANDLING_LOADISISPOLARIZATIONEFFICIENCIES_H_
+#pragma once
 
 #include "MantidDataHandling/CreatePolarizationEfficienciesBase.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -32,5 +31,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADISISPOLARIZATIONEFFICIENCIES_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadInstrument.h b/Framework/DataHandling/inc/MantidDataHandling/LoadInstrument.h
index 18f7c9fef04..05aacf736e8 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadInstrument.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadInstrument.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADINSTRUMENT_H_
-#define MANTID_DATAHANDLING_LOADINSTRUMENT_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 
@@ -96,5 +95,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADINSTRUMENT_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadInstrumentFromNexus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadInstrumentFromNexus.h
index 69d900eb849..751ce3ac5ef 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadInstrumentFromNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadInstrumentFromNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADINSTRUMENTFROMNEXUS_H_
-#define MANTID_DATAHANDLING_LOADINSTRUMENTFROMNEXUS_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -92,5 +91,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADINSTRUMENTFROMNEXUS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadInstrumentFromRaw.h b/Framework/DataHandling/inc/MantidDataHandling/LoadInstrumentFromRaw.h
index 92a67481f04..9c06decdd2f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadInstrumentFromRaw.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadInstrumentFromRaw.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADINSTRUMENTFROMRAW_H_
-#define MANTID_DATAHANDLING_LOADINSTRUMENTFROMRAW_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -92,5 +91,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADINSTRUMENTFROMRAW_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadIsawDetCal.h b/Framework/DataHandling/inc/MantidDataHandling/LoadIsawDetCal.h
index f2be1208398..c86549044b6 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadIsawDetCal.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadIsawDetCal.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADISAWDETCAL_H_
-#define MANTID_DATAHANDLING_LOADISAWDETCAL_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/ExperimentInfo.h"
@@ -84,5 +83,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_ALGORITHM_DIFFRACTIONEVENTREADDETCAL_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadLLB.h b/Framework/DataHandling/inc/MantidDataHandling/LoadLLB.h
index cb297dbd503..d26d86786d4 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadLLB.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadLLB.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADLLB_H_
-#define MANTID_DATAHANDLING_LOADLLB_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/LoadHelper.h"
@@ -65,5 +64,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADLLB_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadLog.h b/Framework/DataHandling/inc/MantidDataHandling/LoadLog.h
index 624b309b06c..399408c33e9 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadLog.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadLog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADLOG_H_
-#define MANTID_DATAHANDLING_LOADLOG_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -131,5 +130,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADLOG_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMLZ.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMLZ.h
index 89575946596..0344b3cd18c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMLZ.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMLZ.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMLZ_H_
-#define MANTID_DATAHANDLING_LOADMLZ_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -87,5 +86,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADMLZ_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMappingTable.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMappingTable.h
index 494568e574d..1ccef3b185f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMappingTable.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMappingTable.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMAPPINGTABLE_H_
-#define MANTID_DATAHANDLING_LOADMAPPINGTABLE_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -70,5 +69,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADRAW_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMask.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMask.h
index 3860267c259..6cb9d80d880 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMask.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMask.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMASK_H_
-#define MANTID_DATAHANDLING_LOADMASK_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace_fwd.h"
 #include "MantidAPI/ParallelAlgorithm.h"
@@ -117,5 +116,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADMASK_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMcStas.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMcStas.h
index 161b965ac89..b398dd85723 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMcStas.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMcStas.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMCSTAS_H_
-#define MANTID_DATAHANDLING_LOADMCSTAS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/IEventWorkspace.h"
@@ -53,5 +52,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LoadMcStas_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMcStasNexus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMcStasNexus.h
index 2deb507ca36..0741ffe0d6d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMcStasNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMcStasNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMCSTASNEXUS_H_
-#define MANTID_DATAHANDLING_LOADMCSTASNEXUS_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidKernel/System.h"
@@ -40,5 +39,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADMCSTASNEXUS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMuonLog.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMuonLog.h
index e91fad03527..a3f9b9aef7f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMuonLog.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMuonLog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMUONLOG_H_
-#define MANTID_DATAHANDLING_LOADMUONLOG_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -80,5 +79,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADMUONLOG_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus.h
index 62a38b328ac..53e709f1bbc 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMUONNEXUS_H_
-#define MANTID_DATAHANDLING_LOADMUONNEXUS_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -113,5 +112,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADMUONNEXUS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus1.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus1.h
index ff31c2fd6ec..9fb3ba6f39d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus1.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus1.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMUONNEXUS1_H_
-#define MANTID_DATAHANDLING_LOADMUONNEXUS1_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -115,5 +114,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADMUONNEXUS1_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus2.h
index 51654a3ecca..c08c01166e1 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadMuonNexus2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMUONNEXUS2_H_
-#define MANTID_DATAHANDLING_LOADMUONNEXUS2_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -89,5 +88,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADMUONNEXUS2_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNGEM.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNGEM.h
index 87e2e9f2602..f5bb976844b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNGEM.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNGEM.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTID_DATAHANDLING_LOADNGEM_H_
-#define MANTID_DATAHANDLING_LOADNGEM_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataObjects/EventWorkspace.h"
@@ -132,5 +131,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_LOADNGEM_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNXSPE.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNXSPE.h
index 5b69ff1bd85..4eac6e92955 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNXSPE.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNXSPE.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNXSPE_H_
-#define MANTID_DATAHANDLING_LOADNXSPE_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidGeometry/Objects/CSGObject.h"
@@ -63,5 +62,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADNXSPE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNXcanSAS.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNXcanSAS.h
index 5608bfb84bc..79ac7262480 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNXcanSAS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNXcanSAS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNXCANSAS_H_
-#define MANTID_DATAHANDLING_LOADNXCANSAS_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -55,5 +54,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADNXCANSAS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNexus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNexus.h
index e298379be94..a5e83b3d929 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNEXUS_H_
-#define MANTID_DATAHANDLING_LOADNEXUS_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -97,5 +96,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADNEXUS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusLogs.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusLogs.h
index 1cb10731cc7..679c713698c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusLogs.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusLogs.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNEXUSLOGS_H_
-#define MANTID_DATAHANDLING_LOADNEXUSLOGS_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 #include <nexus/NeXusFile.hpp>
@@ -86,5 +85,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADNEXUSLOGS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusMonitors.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusMonitors.h
index c2d1fd4b93e..ffbf9a2815d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusMonitors.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusMonitors.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNEXUSMONITORS_H_
-#define MANTID_DATAHANDLING_LOADNEXUSMONITORS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/DeprecatedAlgorithm.h"
@@ -57,5 +56,3 @@ protected:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADNEXUSMONITORS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusMonitors2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusMonitors2.h
index d058fd05d3a..429d903f8b6 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusMonitors2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusMonitors2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNEXUSMONITORS2_H_
-#define MANTID_DATAHANDLING_LOADNEXUSMONITORS2_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace_fwd.h"
 #include "MantidAPI/ParallelAlgorithm.h"
@@ -113,5 +112,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_LOADNEXUSMONITORS2_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusProcessed.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusProcessed.h
index fff204682b2..cde394eb67b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusProcessed.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusProcessed.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNEXUSPROCESSED_H_
-#define MANTID_DATAHANDLING_LOADNEXUSPROCESSED_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -237,5 +236,3 @@ bool UDlesserExecCount(Mantid::NeXus::NXClassInfo elem1,
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADNEXUSPROCESSED_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusProcessed2.h b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusProcessed2.h
index e2577fd333d..19c80c794da 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadNexusProcessed2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadNexusProcessed2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNEXUSPROCESSED2_H_
-#define MANTID_DATAHANDLING_LOADNEXUSPROCESSED2_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -58,5 +57,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADNEXUSPROCESSED2_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadOff.h b/Framework/DataHandling/inc/MantidDataHandling/LoadOff.h
index c36ad88a294..65f28caf7de 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadOff.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadOff.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADOFF_H_
-#define MANTID_DATAHANDLING_LOADOFF_H_
+#pragma once
 #include "MantidDataHandling/MeshFileIO.h"
 #include "MantidDataHandling/ReadMaterial.h"
 #include "MantidKernel/Logger.h"
@@ -41,5 +40,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADOFF_H_ */
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadPDFgetNFile.h b/Framework/DataHandling/inc/MantidDataHandling/LoadPDFgetNFile.h
index e2dd5b5b93f..ef57c6a47f7 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadPDFgetNFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadPDFgetNFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADPDFGETNFILE_H_
-#define MANTID_DATAHANDLING_LOADPDFGETNFILE_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataObjects/Workspace2D.h"
@@ -77,5 +76,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADPDFGETNFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadPLN.h b/Framework/DataHandling/inc/MantidDataHandling/LoadPLN.h
index 5250de4f7b4..116d89d1053 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadPLN.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadPLN.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_LOADPLN_H_
-#define DATAHANDING_LOADPLN_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -120,5 +119,3 @@ protected:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // DATAHANDING_LOADPLN_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadPSIMuonBin.h b/Framework/DataHandling/inc/MantidDataHandling/LoadPSIMuonBin.h
index 129d1e91ca1..b1dbc4addfe 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadPSIMuonBin.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadPSIMuonBin.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADPSIMUONBIN_H_
-#define MANTID_DATAHANDLING_LOADPSIMUONBIN_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/LoadRawHelper.h"
@@ -116,5 +115,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADPSIMUONBIN_H_*/
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadParameterFile.h b/Framework/DataHandling/inc/MantidDataHandling/LoadParameterFile.h
index 18f15a7374a..30cd215e3cd 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadParameterFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadParameterFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADPARAMETERFILE_H_
-#define MANTID_DATAHANDLING_LOADPARAMETERFILE_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 
@@ -76,5 +75,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADPARAMETERFILE_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadPreNexus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadPreNexus.h
index 8e1533b5d3c..b2c75974bd0 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadPreNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadPreNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LoadPreNexus_H_
-#define MANTID_DATAHANDLING_LoadPreNexus_H_
+#pragma once
 
 #include "MantidAPI/IEventWorkspace_fwd.h"
 #include "MantidAPI/IFileLoader.h"
@@ -50,5 +49,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LoadPreNexus_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadPreNexusMonitors.h b/Framework/DataHandling/inc/MantidDataHandling/LoadPreNexusMonitors.h
index 4e0da957a05..1b15e8f587f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadPreNexusMonitors.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadPreNexusMonitors.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADPRENEXUSMONITORS_H_
-#define LOADPRENEXUSMONITORS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -61,5 +60,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*LOADPRENEXUSMONITORS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadQKK.h b/Framework/DataHandling/inc/MantidDataHandling/LoadQKK.h
index 53cabd7d3b6..2826c08bded 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadQKK.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadQKK.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_LOADQKK_H_
-#define DATAHANDING_LOADQKK_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -49,5 +48,4 @@ private:
   void exec() override;
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif // DATAHANDING_LOADQKK_H_
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadRKH.h b/Framework/DataHandling/inc/MantidDataHandling/LoadRKH.h
index b0786e935f7..742db4282a9 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadRKH.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadRKH.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADRKH_H_
-#define MANTID_DATAHANDLING_LOADRKH_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -90,5 +89,4 @@ private:
                          API::Progress &prog, bool readXError = false);
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif /*MANTID_DATAHANDLING_LOADRKH_H_*/
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadRaw3.h b/Framework/DataHandling/inc/MantidDataHandling/LoadRaw3.h
index cec1f741572..c3bad0c283c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadRaw3.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadRaw3.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADRAW3_H_
-#define MANTID_DATAHANDLING_LOADRAW3_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -125,5 +124,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LoadRaw3_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadRawBin0.h b/Framework/DataHandling/inc/MantidDataHandling/LoadRawBin0.h
index eac7be13ca4..0b0b0e114a4 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadRawBin0.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadRawBin0.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADRAWBIN0_H
-#define MANTID_DATAHANDLING_LOADRAWBIN0_H
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -109,5 +108,4 @@ private:
   std::vector<boost::shared_ptr<HistogramData::HistogramX>> m_timeChannelsVec;
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadRawHelper.h b/Framework/DataHandling/inc/MantidDataHandling/LoadRawHelper.h
index 4fa53f3428c..63885039669 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadRawHelper.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadRawHelper.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADRAWHELPER_H_
-#define MANTID_DATAHANDLING_LOADRAWHELPER_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidAPI/Run.h"
@@ -252,5 +251,4 @@ private:
 };
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif /*MANTID_DATAHANDLING_LOADRAW_H_*/
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadRawSpectrum0.h b/Framework/DataHandling/inc/MantidDataHandling/LoadRawSpectrum0.h
index 5ad1724bc4d..2d92979d0db 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadRawSpectrum0.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadRawSpectrum0.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADRAWSPECTRUM0_H
-#define MANTID_DATAHANDLING_LOADRAWSPECTRUM0_H
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -90,5 +89,4 @@ private:
   int64_t m_noTimeRegimes;
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSESANS.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSESANS.h
index 9d3be69ade8..2451cf13ff5 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSESANS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSESANS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSESANS_H_
-#define MANTID_DATAHANDLING_LOADSESANS_H_
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -81,5 +80,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADSESANS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSINQFocus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSINQFocus.h
index e569b316c9d..3078a4f2016 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSINQFocus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSINQFocus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSINQFOCUS_H_
-#define MANTID_DATAHANDLING_LOADSINQFOCUS_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -73,5 +72,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADSINQFOCUS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSNSspec.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSNSspec.h
index df63e73acb9..9f9465d3492 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSNSspec.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSNSspec.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSNSSPEC_H_
-#define MANTID_DATAHANDLING_LOADSNSSPEC_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -64,5 +63,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_LOADSNSPEC_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSPE.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSPE.h
index 2fe1b4b2267..89e09c8afbe 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSPE.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSPE.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSPE_H_
-#define MANTID_DATAHANDLING_LOADSPE_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -62,5 +61,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LoadSPE_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSampleDetailsFromRaw.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSampleDetailsFromRaw.h
index 1c3bc50ddc0..fb273f82cb8 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSampleDetailsFromRaw.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSampleDetailsFromRaw.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDDATAHANDLING_LOADSAMPLEDETAILSFROMRAW_H_
-#define MANTIDDATAHANDLING_LOADSAMPLEDETAILSFROMRAW_H_
+#pragma once
 
 //-----------------------------------------------------
 // Includes
@@ -55,5 +54,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTIDDATAHANDLING_LOADSAMPLEDETAILSFROMRAW_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSampleEnvironment.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSampleEnvironment.h
index 98fa6031a2b..8ba473ab806 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSampleEnvironment.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSampleEnvironment.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDLING_LOAD_ENVIRONMENT_H_
-#define DATAHANDLING_LOAD_ENVIRONMENT_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MeshFileIO.h"
@@ -54,5 +53,3 @@ private:
 
 } // end namespace DataHandling
 } // namespace Mantid
-
-#endif /* DATAHANDLING_LOAD_ENVIRONMENT_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSampleShape.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSampleShape.h
index 8d3048c080e..2d3d329ddce 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSampleShape.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSampleShape.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDLING_LOAD_SHAPE_H_
-#define DATAHANDLING_LOAD_SHAPE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/MeshFileIO.h"
@@ -55,5 +54,4 @@ void DLLExport rotate(Geometry::MeshObject &sampleMesh,
                       API::MatrixWorkspace_const_sptr inputWS);
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif /* DATAHANDLING_LOAD_SHAPE_H_ */
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSassena.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSassena.h
index fe12c5a513d..bdab1283344 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSassena.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSassena.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSASSENA_H_
-#define MANTID_DATAHANDLING_LOADSASSENA_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -100,5 +99,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_LOADSASSENA_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSpec.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSpec.h
index c156c1fed0a..e875c3a9a77 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSpec.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSpec.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSPEC_H_
-#define MANTID_DATAHANDLING_LOADSPEC_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -68,5 +67,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_LOADSPEC_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSpice2D.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSpice2D.h
index b649529eb8a..57b499e60df 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSpice2D.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSpice2D.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LoadSpice2D_H
-#define MANTID_DATAHANDLING_LoadSpice2D_H
+#pragma once
 
 #include "MantidAPI/IFileLoader.h"
 #include "MantidDataHandling/XmlHandler.h"
@@ -133,5 +132,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSpiceAscii.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSpiceAscii.h
index 0e5e112753b..ac7ee0710b5 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSpiceAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSpiceAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSPICEASCII_H_
-#define MANTID_DATAHANDLING_LOADSPICEASCII_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/ITableWorkspace_fwd.h"
@@ -75,5 +74,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADSPICEASCII_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSpiceXML2DDet.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSpiceXML2DDet.h
index 448e6382782..8d4b2cab9d8 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSpiceXML2DDet.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSpiceXML2DDet.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSPICEXML2DDET_H_
-#define MANTID_DATAHANDLING_LOADSPICEXML2DDET_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/ITableWorkspace_fwd.h"
@@ -142,5 +141,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADSPICEXML2DDET_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadStl.h b/Framework/DataHandling/inc/MantidDataHandling/LoadStl.h
index c5d36c62f80..1e9e80755cb 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadStl.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadStl.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSTL_H_
-#define MANTID_DATAHANDLING_LOADSTL_H_
+#pragma once
 #include "MantidDataHandling/LoadSampleShape.h"
 #include "MantidDataHandling/MeshFileIO.h"
 #include "MantidDataHandling/ReadMaterial.h"
@@ -66,5 +65,4 @@ protected:
 };
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif /* MANTID_DATAHANDLING_LOADSTL_H_ */
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadStlFactory.h b/Framework/DataHandling/inc/MantidDataHandling/LoadStlFactory.h
index 73812930726..15b4cabf2f9 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadStlFactory.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadStlFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSTLFACTORY_H_
-#define MANTID_DATAHANDLING_LOADSTLFACTORY_H_
+#pragma once
 
 #include "MantidDataHandling/DllConfig.h"
 #include "MantidDataHandling/LoadAsciiStl.h"
@@ -32,5 +31,4 @@ public:
 };
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif
\ No newline at end of file
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadSwans.h b/Framework/DataHandling/inc/MantidDataHandling/LoadSwans.h
index 7fe597619f5..3417868ca2c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadSwans.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadSwans.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSWANS_H_
-#define MANTID_DATAHANDLING_LOADSWANS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/IFileLoader.h"
@@ -53,5 +52,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_LOADSWANS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadTBL.h b/Framework/DataHandling/inc/MantidDataHandling/LoadTBL.h
index 483723ba13d..e06cee458cc 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadTBL.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadTBL.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADTBL_H_
-#define MANTID_DATAHANDLING_LOADTBL_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -65,5 +64,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_LOADTBL_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/LoadTOFRawNexus.h b/Framework/DataHandling/inc/MantidDataHandling/LoadTOFRawNexus.h
index ffe7b944a6b..04bd38da86b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/LoadTOFRawNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/LoadTOFRawNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADTOFRAWNEXUS_H_
-#define MANTID_DATAHANDLING_LOADTOFRAWNEXUS_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -109,5 +108,3 @@ protected:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLINGLOADTOFRAWNEXUS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/MaskDetectors.h b/Framework/DataHandling/inc/MantidDataHandling/MaskDetectors.h
index 43f9af110b3..7c31f9358ea 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/MaskDetectors.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/MaskDetectors.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_MASKDETECTORS_H_
-#define MANTID_DATAHANDLING_MASKDETECTORS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataObjects/EventWorkspace.h"
@@ -126,5 +125,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_MASKDETECTORS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/MaskDetectorsInShape.h b/Framework/DataHandling/inc/MantidDataHandling/MaskDetectorsInShape.h
index 53862bfb39f..654a65d570f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/MaskDetectorsInShape.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/MaskDetectorsInShape.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_MASKDETECTORSINSHAPE_H_
-#define MANTID_DATAHANDLING_MASKDETECTORSINSHAPE_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 
@@ -69,5 +68,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_MASKDETECTORSINSHAPE_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/MaskSpectra.h b/Framework/DataHandling/inc/MantidDataHandling/MaskSpectra.h
index 9099da96791..c69016613fe 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/MaskSpectra.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/MaskSpectra.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_MASKSPECTRA_H_
-#define MANTID_DATAHANDLING_MASKSPECTRA_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -37,5 +36,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_MASKSPECTRA_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/MeshFileIO.h b/Framework/DataHandling/inc/MantidDataHandling/MeshFileIO.h
index 3483f5039c4..56b15366c24 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/MeshFileIO.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/MeshFileIO.h
@@ -9,8 +9,7 @@
 #include "MantidKernel/Matrix.h"
 #include "MantidKernel/V3D.h"
 
-#ifndef MANTID_DATAHANDLING_MESHFILEIO_H_
-#define MANTID_DATAHANDLING_MESHFILEIO_H_
+#pragma once
 namespace {
 Mantid::Kernel::Logger g_log("MeshFileIO");
 }
@@ -92,5 +91,4 @@ inline ScaleUnits getScaleType(const std::string &scaleProperty) {
 }
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif /*MANTID_DATAHANDLING_MESHFILEIO_H_*/
\ No newline at end of file
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ModifyDetectorDotDatFile.h b/Framework/DataHandling/inc/MantidDataHandling/ModifyDetectorDotDatFile.h
index d30e9ef4312..a6eaeb60fdd 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ModifyDetectorDotDatFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ModifyDetectorDotDatFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_MODIFYDETECTORDOTDATFILE_H_
-#define MANTID_DATAHANDLING_MODIFYDETECTORDOTDATFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -50,5 +49,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_MODIFYDETECTORDOTDATFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/MoveInstrumentComponent.h b/Framework/DataHandling/inc/MantidDataHandling/MoveInstrumentComponent.h
index 0c210fd8b45..1a66cd822ee 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/MoveInstrumentComponent.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/MoveInstrumentComponent.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_MOVEINSTRUMENTCOMPONENT_H_
-#define MANTID_DATAHANDLING_MOVEINSTRUMENTCOMPONENT_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 #include "MantidGeometry/Instrument/Component.h"
@@ -74,5 +73,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_MOVEINSTRUMENTCOMPONENT_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/NXcanSASDefinitions.h b/Framework/DataHandling/inc/MantidDataHandling/NXcanSASDefinitions.h
index 8f3b4c9e1a1..292ffa29eb2 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/NXcanSASDefinitions.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/NXcanSASDefinitions.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_NXCANSASDEFINITIONS_H_
-#define MANTID_DATAHANDLING_NXCANSASDEFINITIONS_H_
+#pragma once
 
 #include <string>
 
@@ -139,5 +138,4 @@ const std::string sasTransmissionSpectrumT = "T";
 const std::string sasTransmissionSpectrumTdev = "Tdev";
 } // namespace NXcanSAS
 } // namespace DataHandling
-} // namespace Mantid
-#endif
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/NexusTester.h b/Framework/DataHandling/inc/MantidDataHandling/NexusTester.h
index 62e22a025cb..a426ad64598 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/NexusTester.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/NexusTester.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_NEXUSTESTER_H_
-#define MANTID_DATAHANDLING_NEXUSTESTER_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -36,5 +35,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_NEXUSTESTER_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ORNLDataArchive.h b/Framework/DataHandling/inc/MantidDataHandling/ORNLDataArchive.h
index 3d01d27b1bc..3b840f78cc4 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ORNLDataArchive.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ORNLDataArchive.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ORNLDATAARCHIVE_H_
-#define MANTID_DATAHANDLING_ORNLDATAARCHIVE_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -41,5 +40,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_ORNLDATAARCHIVE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/PDLoadCharacterizations.h b/Framework/DataHandling/inc/MantidDataHandling/PDLoadCharacterizations.h
index 845ccbbfc13..a23da323949 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/PDLoadCharacterizations.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/PDLoadCharacterizations.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_PDLOADCHARACTERIZATIONS_H_
-#define MANTID_DATAHANDLING_PDLOADCHARACTERIZATIONS_H_
+#pragma once
 
 #include <iosfwd>
 
@@ -45,5 +44,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_PDLOADCHARACTERIZATIONS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ParallelEventLoader.h b/Framework/DataHandling/inc/MantidDataHandling/ParallelEventLoader.h
index 3fd152f999d..9b8fe418a88 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ParallelEventLoader.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ParallelEventLoader.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_PARALLELEVENTLOADER_H_
-#define MANTID_DATAHANDLING_PARALLELEVENTLOADER_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -43,5 +42,3 @@ public:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_PARALLELEVENTLOADER_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/PatchBBY.h b/Framework/DataHandling/inc/MantidDataHandling/PatchBBY.h
index fb3693e54ff..879a975b118 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/PatchBBY.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/PatchBBY.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_PATCHBBY_H_
-#define DATAHANDING_PATCHBBY_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -50,5 +49,3 @@ protected:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // DATAHANDING_PATCHBBY_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/PrecompiledHeader.h b/Framework/DataHandling/inc/MantidDataHandling/PrecompiledHeader.h
index 0977202b5c1..11e454e4d7c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/PrecompiledHeader.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/PrecompiledHeader.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_PRECOMPILEDHEADER_H_
-#define MANTID_DATAHANDLING_PRECOMPILEDHEADER_H_
+#pragma once
 
 // Algorithm
 #include "MantidAPI/Algorithm.h"
@@ -15,5 +14,3 @@
 #include <nexus/NeXusFile.hpp>
 #include <nexus/NeXusException.hpp>
 // clang-format on
-
-#endif // MANTID_DATAHANDLING_PRECOMPILEDHEADER_H_
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ProcessBankData.h b/Framework/DataHandling/inc/MantidDataHandling/ProcessBankData.h
index 6e3994d8b7f..d2e643bb24b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ProcessBankData.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ProcessBankData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_PROCESSBANKDATA_H
-#define MANTID_DATAHANDLING_PROCESSBANKDATA_H
+#pragma once
 
 #include "MantidDataHandling/BankPulseTimes.h"
 #include "MantidGeometry/IDTypes.h"
@@ -96,5 +95,3 @@ private:
 }; // ENDDEF-CLASS ProcessBankData
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/RawFileInfo.h b/Framework/DataHandling/inc/MantidDataHandling/RawFileInfo.h
index 64b08bb78b6..d7685a70e42 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/RawFileInfo.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/RawFileInfo.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDDATAHANDLING_RAWFILEINFO_H_
-#define MANTIDDATAHANDLING_RAWFILEINFO_H_
+#pragma once
 
 //------------------------------------
 // Includes
@@ -70,5 +69,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTIDDATAHANDLING_RAWFILEINFO_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/ReadMaterial.h b/Framework/DataHandling/inc/MantidDataHandling/ReadMaterial.h
index d953e2711e6..0eeac974c01 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/ReadMaterial.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/ReadMaterial.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ReadMaterial_H_
-#define MANTID_DATAHANDLING_ReadMaterial_H_
+#pragma once
 
 #include "MantidKernel/EmptyValues.h"
 #include "MantidKernel/MaterialBuilder.h"
@@ -103,5 +102,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_ReadMaterial_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/RemoveLogs.h b/Framework/DataHandling/inc/MantidDataHandling/RemoveLogs.h
index edafe79c6cb..8734bbe38fb 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/RemoveLogs.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/RemoveLogs.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_REMOVELOGS_H_
-#define MANTID_DATAHANDLING_REMOVELOGS_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -86,5 +85,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_REMOVELOGS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/RenameLog.h b/Framework/DataHandling/inc/MantidDataHandling/RenameLog.h
index 13421421ddc..f1a8a615de2 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/RenameLog.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/RenameLog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_RENAMELOG_H_
-#define MANTID_DATAHANDLING_RENAMELOG_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -44,5 +43,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_RENAMELOG_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/RotateInstrumentComponent.h b/Framework/DataHandling/inc/MantidDataHandling/RotateInstrumentComponent.h
index 783e3c04490..0383426c66c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/RotateInstrumentComponent.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/RotateInstrumentComponent.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ROTATEINSTRUMENTCOMPONENT_H_
-#define MANTID_DATAHANDLING_ROTATEINSTRUMENTCOMPONENT_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 #include "MantidGeometry/Instrument/Component.h"
@@ -73,5 +72,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_ROTATEINSTRUMENTCOMPONENT_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/RotateSource.h b/Framework/DataHandling/inc/MantidDataHandling/RotateSource.h
index fa704d7af16..f2122c90a60 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/RotateSource.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/RotateSource.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ROTATESOURCE_H_
-#define MANTID_DATAHANDLING_ROTATESOURCE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -38,5 +37,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_ROTATESOURCE_H_ */
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentFactory.h b/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentFactory.h
index 0ec20d79f1e..970be314c9e 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentFactory.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAMPLEENVIRONMENTFACTORY_H_
-#define MANTID_DATAHANDLING_SAMPLEENVIRONMENTFACTORY_H_
+#pragma once
 
 #include "MantidDataHandling/DllConfig.h"
 #include "MantidDataHandling/SampleEnvironmentSpec.h"
@@ -77,5 +76,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAMPLEENVIRONMENTFACTORY_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentSpec.h b/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentSpec.h
index 594ac2b69af..bfc40cde254 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentSpec.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentSpec.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAMPLEENVIRONMENTSPEC_H_
-#define MANTID_DATAHANDLING_SAMPLEENVIRONMENTSPEC_H_
+#pragma once
 
 #include "MantidDataHandling/DllConfig.h"
 #include "MantidGeometry/Instrument/Container.h"
@@ -61,5 +60,3 @@ using SampleEnvironmentSpec_const_uptr =
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAMPLEENVIRONMENTSPEC_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentSpecParser.h b/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentSpecParser.h
index 9692418e0dd..4163307f7ef 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentSpecParser.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SampleEnvironmentSpecParser.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAMPLEENVIRONMENTSPECPARSER_H_
-#define MANTID_DATAHANDLING_SAMPLEENVIRONMENTSPECPARSER_H_
+#pragma once
 
 #include "MantidDataHandling/DllConfig.h"
 #include "MantidDataHandling/SampleEnvironmentSpec.h"
@@ -67,5 +66,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAMPLEENVIRONMENTSPECPARSER_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveANSTOAscii.h b/Framework/DataHandling/inc/MantidDataHandling/SaveANSTOAscii.h
index b7c905c9d0f..0bdfc77f291 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveANSTOAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveANSTOAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEANSTOASCII_H_
-#define MANTID_DATAHANDLING_SAVEANSTOASCII_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/DeprecatedAlgorithm.h"
@@ -52,5 +51,4 @@ private:
 };
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif /*  MANTID_DATAHANDLING_SAVEANSTO_H_  */
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveAscii.h b/Framework/DataHandling/inc/MantidDataHandling/SaveAscii.h
index 2e259b04383..5f642bc6d1f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEASCII_H_
-#define MANTID_DATAHANDLING_SAVEASCII_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -50,5 +49,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_SAVEASCII_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveAscii2.h b/Framework/DataHandling/inc/MantidDataHandling/SaveAscii2.h
index 4f189859690..eff74596efa 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveAscii2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveAscii2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SaveAscii2_H_
-#define MANTID_DATAHANDLING_SaveAscii2_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -103,5 +102,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_SaveAscii2_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveBankScatteringAngles.h b/Framework/DataHandling/inc/MantidDataHandling/SaveBankScatteringAngles.h
index 99714c3247a..2a53d11faa8 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveBankScatteringAngles.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveBankScatteringAngles.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEBANKSCATTERINGANGLES_H_
-#define MANTID_DATAHANDLING_SAVEBANKSCATTERINGANGLES_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -38,5 +37,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_SAVEBANKSCATTERINGANGLES_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveCSV.h b/Framework/DataHandling/inc/MantidDataHandling/SaveCSV.h
index 633927abc9a..7ea37b0c3ff 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveCSV.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveCSV.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVECSV_H_
-#define MANTID_DATAHANDLING_SAVECSV_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -109,5 +108,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_SAVECSV_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveCalFile.h b/Framework/DataHandling/inc/MantidDataHandling/SaveCalFile.h
index 4484b51821c..814261ef01d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveCalFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveCalFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVECALFILE_H_
-#define MANTID_DATAHANDLING_SAVECALFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -63,5 +62,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVECALFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveCanSAS1D.h b/Framework/DataHandling/inc/MantidDataHandling/SaveCanSAS1D.h
index 00e9589fe83..3591c440196 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveCanSAS1D.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveCanSAS1D.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SaveCanSAS1D_H
-#define MANTID_DATAHANDLING_SaveCanSAS1D_H
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -152,5 +151,3 @@ protected:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveCanSAS1D2.h b/Framework/DataHandling/inc/MantidDataHandling/SaveCanSAS1D2.h
index 0998ead565f..d0f23b7092b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveCanSAS1D2.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveCanSAS1D2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVECANSAS1D2_H
-#define MANTID_DATAHANDLING_SAVECANSAS1D2_H
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -91,5 +90,3 @@ protected:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveDaveGrp.h b/Framework/DataHandling/inc/MantidDataHandling/SaveDaveGrp.h
index 8d4876f651f..260aaf8f181 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveDaveGrp.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveDaveGrp.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDAVEGRP_H_
-#define MANTID_DATAHANDLING_SAVEDAVEGRP_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -58,5 +57,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEDAVEGRP_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveDetectorsGrouping.h b/Framework/DataHandling/inc/MantidDataHandling/SaveDetectorsGrouping.h
index bc76800bf56..74c401a3473 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveDetectorsGrouping.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveDetectorsGrouping.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDETECTORSGROUPING_H_
-#define MANTID_DATAHANDLING_SAVEDETECTORSGROUPING_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataObjects/GroupingWorkspace.h"
@@ -63,5 +62,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEDETECTORSGROUPING_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveDiffCal.h b/Framework/DataHandling/inc/MantidDataHandling/SaveDiffCal.h
index 6eef65db684..e8fe9599b86 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveDiffCal.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveDiffCal.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDIFFCAL_H_
-#define MANTID_DATAHANDLING_SAVEDIFFCAL_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/ITableWorkspace_fwd.h"
@@ -50,5 +49,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEDIFFCAL_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveDiffFittingAscii.h b/Framework/DataHandling/inc/MantidDataHandling/SaveDiffFittingAscii.h
index cca4c9fa263..dcd6c22ba1d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveDiffFittingAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveDiffFittingAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDIFFFITTINGASCII_H_
-#define MANTID_DATAHANDLING_SAVEDIFFFITTINGASCII_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -82,5 +81,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_SAVEDIFFFITTINGASCII_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveDspacemap.h b/Framework/DataHandling/inc/MantidDataHandling/SaveDspacemap.h
index d8e7ac1cce4..677e333009e 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveDspacemap.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveDspacemap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDSPACEMAP_H_
-#define MANTID_DATAHANDLING_SAVEDSPACEMAP_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataObjects/OffsetsWorkspace.h"
@@ -47,5 +46,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEDSPACEMAP_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveFITS.h b/Framework/DataHandling/inc/MantidDataHandling/SaveFITS.h
index fb820f5b068..598722ddeba 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveFITS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveFITS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEFITS_H_
-#define MANTID_DATAHANDLING_SAVEFITS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -73,5 +72,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEFITS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveFocusedXYE.h b/Framework/DataHandling/inc/MantidDataHandling/SaveFocusedXYE.h
index 29e28f44ba7..7066d366f4b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveFocusedXYE.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveFocusedXYE.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_SAVEFOCUSEDXYE_H_
-#define DATAHANDING_SAVEFOCUSEDXYE_H_
+#pragma once
 
 #include "MantidAPI/SerialAlgorithm.h"
 
@@ -104,5 +103,4 @@ private:
   std::string m_comment;
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif // DATAHANDING_SAVEFOCUSEDXYE_H_
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveFullprofResolution.h b/Framework/DataHandling/inc/MantidDataHandling/SaveFullprofResolution.h
index 752f3705ee0..5c84972f33e 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveFullprofResolution.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveFullprofResolution.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEFullprofRESOLUTION_H_
-#define MANTID_DATAHANDLING_SAVEFullprofRESOLUTION_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataObjects/TableWorkspace.h"
@@ -81,5 +80,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEFullprofRESOLUTION_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveGDA.h b/Framework/DataHandling/inc/MantidDataHandling/SaveGDA.h
index 7319c4bb925..cb18f94e051 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveGDA.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveGDA.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEGDA_H_
-#define MANTID_DATAHANDLING_SAVEGDA_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -55,5 +54,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_SAVEGDA_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveGSASInstrumentFile.h b/Framework/DataHandling/inc/MantidDataHandling/SaveGSASInstrumentFile.h
index b3465ba1de1..95c151bbcde 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveGSASInstrumentFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveGSASInstrumentFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_ALGORITHMS_SAVEGSASINSTRUMENTFILE_H_
-#define MANTID_ALGORITHMS_SAVEGSASINSTRUMENTFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/ITableWorkspace_fwd.h"
@@ -165,5 +164,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_ALGORITHMS_SAVEGSASINSTRUMENTFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveGSS.h b/Framework/DataHandling/inc/MantidDataHandling/SaveGSS.h
index 0d5698a914f..e7ef93dc392 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveGSS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveGSS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_SAVEGSS_H_
-#define DATAHANDING_SAVEGSS_H_
+#pragma once
 
 #include "MantidAPI/Run.h"
 #include "MantidAPI/SerialAlgorithm.h"
@@ -166,5 +165,4 @@ private:
   bool m_overwrite_std_bank_header;
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif // DATAHANDING_SAVEGSS_H_
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveILLCosmosAscii.h b/Framework/DataHandling/inc/MantidDataHandling/SaveILLCosmosAscii.h
index 22690a3e15d..d9fc9c73b20 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveILLCosmosAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveILLCosmosAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SaveILLCosmosAscii_H_
-#define MANTID_DATAHANDLING_SaveILLCosmosAscii_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/DeprecatedAlgorithm.h"
@@ -53,5 +52,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_SaveILLCosmosAscii_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveISISNexus.h b/Framework/DataHandling/inc/MantidDataHandling/SaveISISNexus.h
index e8b4fcc4358..c54da2896ed 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveISISNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveISISNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEISISNEXUS_H_
-#define MANTID_DATAHANDLING_SAVEISISNEXUS_H_
+#pragma once
 
 #include "../../src/LoadRaw/isisraw2.h"
 #include "MantidAPI/Algorithm.h"
@@ -143,5 +142,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_SAVEISISNEXUS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveIsawDetCal.h b/Framework/DataHandling/inc/MantidDataHandling/SaveIsawDetCal.h
index 70588ae64f6..ee5edac22ee 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveIsawDetCal.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveIsawDetCal.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEISAWDETCAL_H_
-#define MANTID_DATAHANDLING_SAVEISAWDETCAL_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidGeometry/Instrument_fwd.h"
@@ -55,5 +54,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEISAWDETCAL_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveMask.h b/Framework/DataHandling/inc/MantidDataHandling/SaveMask.h
index f1d47c422a8..4c286ed55c9 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveMask.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveMask.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEMASKINGTOFILE_H_
-#define MANTID_DATAHANDLING_SAVEMASKINGTOFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -46,5 +45,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEMASKINGTOFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveNISTDAT.h b/Framework/DataHandling/inc/MantidDataHandling/SaveNISTDAT.h
index 74f8b649600..07ff65e22c9 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveNISTDAT.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveNISTDAT.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_ALGORITHMS_SAVENISTDAT_H_
-#define MANTID_ALGORITHMS_SAVENISTDAT_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -53,5 +52,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_ALGORITHMS_SAVENISTDAT_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveNXSPE.h b/Framework/DataHandling/inc/MantidDataHandling/SaveNXSPE.h
index 446268157ce..d41a6212e00 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveNXSPE.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveNXSPE.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENXSPE_H_
-#define MANTID_DATAHANDLING_SAVENXSPE_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -78,5 +77,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_SAVENXSPE_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveNXTomo.h b/Framework/DataHandling/inc/MantidDataHandling/SaveNXTomo.h
index 6f404c8457b..919f3816708 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveNXTomo.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveNXTomo.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENXTOMO_H_
-#define MANTID_DATAHANDLING_SAVENXTOMO_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -124,5 +123,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_SAVENXTOMO_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveNXcanSAS.h b/Framework/DataHandling/inc/MantidDataHandling/SaveNXcanSAS.h
index e434b1b1abd..3e00f540af1 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveNXcanSAS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveNXcanSAS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENXCANSAS_H_
-#define MANTID_DATAHANDLING_SAVENXCANSAS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -50,5 +49,3 @@ makeCanSASRelaxedName(const std::string &input);
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVENXCANSAS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveNexus.h b/Framework/DataHandling/inc/MantidDataHandling/SaveNexus.h
index b30c075beeb..621a64cff31 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENEXUS_H_
-#define MANTID_DATAHANDLING_SAVENEXUS_H_
+#pragma once
 
 #include "MantidAPI/SerialAlgorithm.h"
 #include <climits>
@@ -77,5 +76,3 @@ protected:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_SAVENEXUS_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveNexusESS.h b/Framework/DataHandling/inc/MantidDataHandling/SaveNexusESS.h
index fb52db78c94..e7fb995e865 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveNexusESS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveNexusESS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENEXUSESS_H_
-#define MANTID_DATAHANDLING_SAVENEXUSESS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -42,5 +41,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVENEXUSESS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveNexusGeometry.h b/Framework/DataHandling/inc/MantidDataHandling/SaveNexusGeometry.h
index fff3604f30a..d07e95d253d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveNexusGeometry.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveNexusGeometry.h
@@ -12,8 +12,7 @@
  * @author Takudzwa Makoni, RAL (UKRI), ISIS
  * @date 16/08/2019
  */
-#ifndef MANTID_DATAHANDLING_SAVENEXUSGEOMETRY_H_
-#define MANTID_DATAHANDLING_SAVENEXUSGEOMETRY_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -36,5 +35,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVENEXUSGEOMETRY_H_ */
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveNexusProcessed.h b/Framework/DataHandling/inc/MantidDataHandling/SaveNexusProcessed.h
index 8f769f01186..6ab2f7ba1c6 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveNexusProcessed.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveNexusProcessed.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENEXUSPROCESSED_H_
-#define MANTID_DATAHANDLING_SAVENEXUSPROCESSED_H_
+#pragma once
 
 #include "MantidAPI/Progress.h"
 #include "MantidAPI/SerialAlgorithm.h"
@@ -106,5 +105,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_SAVENEXUSPROCESSED_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveOpenGenieAscii.h b/Framework/DataHandling/inc/MantidDataHandling/SaveOpenGenieAscii.h
index 022cd98bab0..03053999c9f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveOpenGenieAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveOpenGenieAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDING_SAVEOPENGENIEASCII_H_
-#define DATAHANDING_SAVEOPENGENIEASCII_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -102,5 +101,4 @@ private:
   const std::string m_intType = "Integer";
 };
 } // namespace DataHandling
-} // namespace Mantid
-#endif // DATAHANDING_SAVEOPENGENIEASCII_H_
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SavePAR.h b/Framework/DataHandling/inc/MantidDataHandling/SavePAR.h
index 65a852b25e5..50525c698a7 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SavePAR.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SavePAR.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEPAR_H_
-#define SAVEPAR_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 
@@ -81,5 +80,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*SAVEPAR_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SavePDFGui.h b/Framework/DataHandling/inc/MantidDataHandling/SavePDFGui.h
index a13dc4db268..305db7dbe06 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SavePDFGui.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SavePDFGui.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEPDFGUI_H_
-#define MANTID_DATAHANDLING_SAVEPDFGUI_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -43,5 +42,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVEPDFGUI_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SavePHX.h b/Framework/DataHandling/inc/MantidDataHandling/SavePHX.h
index 447b6eb1379..640e1a25b0b 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SavePHX.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SavePHX.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEPHX_H_
-#define SAVEPHX_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 
@@ -67,5 +66,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*SAVEPHX_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveParameterFile.h b/Framework/DataHandling/inc/MantidDataHandling/SaveParameterFile.h
index 9b6f7acc44a..3cc796c68f9 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveParameterFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveParameterFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_ALGORITHMS_SAVEPARAMETERFILE_H_
-#define MANTID_ALGORITHMS_SAVEPARAMETERFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidGeometry/Instrument/FitParameter.h"
@@ -41,5 +40,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_ALGORITHMS_SAVEPARAMETERFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveRKH.h b/Framework/DataHandling/inc/MantidDataHandling/SaveRKH.h
index 9fa3126ae63..21864cc3933 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveRKH.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveRKH.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVERKH_H_
-#define MANTID_DATAHANDLING_SAVERKH_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -71,5 +70,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_SAVERKH_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveRMCProfile.h b/Framework/DataHandling/inc/MantidDataHandling/SaveRMCProfile.h
index e27ba506f3d..cce8b3d8a49 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveRMCProfile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveRMCProfile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVERMCPROFILE_H_
-#define MANTID_DATAHANDLING_SAVERMCPROFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -43,5 +42,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVERMCPROFILE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveReflCustomAscii.h b/Framework/DataHandling/inc/MantidDataHandling/SaveReflCustomAscii.h
index 682b5f94ce2..6a1d5ca4d35 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveReflCustomAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveReflCustomAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SaveReflCustomAscii_H_
-#define MANTID_DATAHANDLING_SaveReflCustomAscii_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -56,5 +55,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_SaveReflCustomAscii_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveReflThreeColumnAscii.h b/Framework/DataHandling/inc/MantidDataHandling/SaveReflThreeColumnAscii.h
index 10fc838df88..75f1a4ddb43 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveReflThreeColumnAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveReflThreeColumnAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEREFLTHREECOLUMNASCII_H_
-#define MANTID_DATAHANDLING_SAVEREFLTHREECOLUMNASCII_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -57,5 +56,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_SAVEREFLTHREECOLUMNASCII_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveReflectometryAscii.h b/Framework/DataHandling/inc/MantidDataHandling/SaveReflectometryAscii.h
index 51c8a3bf2a8..e03bde6c999 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveReflectometryAscii.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveReflectometryAscii.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SaveReflectometryAscii_H_
-#define MANTID_DATAHANDLING_SaveReflectometryAscii_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -87,5 +86,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_SaveReflectometryAscii_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveSESANS.h b/Framework/DataHandling/inc/MantidDataHandling/SaveSESANS.h
index ec39db4957e..abb38eca6d0 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveSESANS.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveSESANS.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVESESANS_H_
-#define MANTID_DATAHANDLING_SAVESESANS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -75,5 +74,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SAVESESANS_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveSPE.h b/Framework/DataHandling/inc/MantidDataHandling/SaveSPE.h
index e9918ace09b..44e1fbb0125 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveSPE.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveSPE.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVESPE_H_
-#define MANTID_DATAHANDLING_SAVESPE_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -121,5 +120,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_SAVESPE_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveSampleEnvironmentAndShape.h b/Framework/DataHandling/inc/MantidDataHandling/SaveSampleEnvironmentAndShape.h
index e0756268b61..642ec30fa58 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveSampleEnvironmentAndShape.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveSampleEnvironmentAndShape.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDLING_SAVE_ENVIRONMENT_H_
-#define DATAHANDLING_SAVE_ENVIRONMENT_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/Matrix.h"
@@ -58,5 +57,3 @@ const Mantid::Geometry::MeshObject &
 toMeshObject(const Mantid::Geometry::IObject &object);
 } // end namespace DataHandling
 } // namespace Mantid
-
-#endif /* DATAHANDLING_SAVE_ENVIRONMENT_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveStl.h b/Framework/DataHandling/inc/MantidDataHandling/SaveStl.h
index 80017f89f2a..416fc51e5b3 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveStl.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveStl.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVESTL_H_
-#define MANTID_DATAHANDLING_SAVESTL_H_
+#pragma once
 
 #include "MantidDataHandling/MeshFileIO.h"
 #include "MantidKernel/BinaryStreamWriter.h"
@@ -40,5 +39,4 @@ private:
 };
 
 } // namespace DataHandling
-} // namespace Mantid
-#endif /* MANTID_DATAHANDLING_SAVESTL_H_ */
\ No newline at end of file
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveTBL.h b/Framework/DataHandling/inc/MantidDataHandling/SaveTBL.h
index 8f6c3ee4316..2f18dcdc83d 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveTBL.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveTBL.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVETBL_H_
-#define MANTID_DATAHANDLING_SAVETBL_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -61,5 +60,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*  MANTID_DATAHANDLING_SAVETBL_H_  */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveToSNSHistogramNexus.h b/Framework/DataHandling/inc/MantidDataHandling/SaveToSNSHistogramNexus.h
index 698fdb384ac..b2c591cb256 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveToSNSHistogramNexus.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveToSNSHistogramNexus.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVESNSNEXUS_H_
-#define MANTID_DATAHANDLING_SAVESNSNEXUS_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -131,5 +130,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SaveVTK.h b/Framework/DataHandling/inc/MantidDataHandling/SaveVTK.h
index 04546a2c171..2adc2c6184f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SaveVTK.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SaveVTK.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEVTP_H_
-#define MANTID_DATAHANDLING_SAVEVTP_H_
+#pragma once
 
 //---------------------------------------------------
 // Includes
@@ -82,5 +81,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif // MANTID_DATAHANDLING_SAVEVTP_H_
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SetBeam.h b/Framework/DataHandling/inc/MantidDataHandling/SetBeam.h
index 390ba70d47c..d5f75d1d3c2 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SetBeam.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SetBeam.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SETBEAM_H_
-#define MANTID_DATAHANDLING_SETBEAM_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -33,5 +32,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SETBEAM_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SetSample.h b/Framework/DataHandling/inc/MantidDataHandling/SetSample.h
index 34e50943abf..d06a69145c6 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SetSample.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SetSample.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SETSAMPLE_H_
-#define MANTID_DATAHANDLING_SETSAMPLE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidDataHandling/DllConfig.h"
@@ -62,5 +61,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SETSAMPLE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SetSampleMaterial.h b/Framework/DataHandling/inc/MantidDataHandling/SetSampleMaterial.h
index f9b7bdff274..496aec8cccd 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SetSampleMaterial.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SetSampleMaterial.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SetSampleMaterial_H_
-#define MANTID_DATAHANDLING_SetSampleMaterial_H_
+#pragma once
 
 #include "MantidAPI/DistributedAlgorithm.h"
 #include "MantidDataHandling/ReadMaterial.h"
@@ -53,5 +52,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SetSampleMaterial_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SetScalingPSD.h b/Framework/DataHandling/inc/MantidDataHandling/SetScalingPSD.h
index 1b2181ed259..4c59658e91f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SetScalingPSD.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SetScalingPSD.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SETSCALINGPSD_H_
-#define MANTID_DATAHANDLING_SETSCALINGPSD_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -93,5 +92,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_SETSCALINGPSD_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/SortTableWorkspace.h b/Framework/DataHandling/inc/MantidDataHandling/SortTableWorkspace.h
index c1d9afbd934..46b2e59dbc0 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/SortTableWorkspace.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/SortTableWorkspace.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SORTTABLEWORKSPACE_H_
-#define MANTID_DATAHANDLING_SORTTABLEWORKSPACE_H_
+#pragma once
 
 #include "MantidAPI/ParallelAlgorithm.h"
 #include "MantidKernel/System.h"
@@ -32,5 +31,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_SORTTABLEWORKSPACE_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/StartAndEndTimeFromNexusFileExtractor.h b/Framework/DataHandling/inc/MantidDataHandling/StartAndEndTimeFromNexusFileExtractor.h
index e67390053a5..6241b76be76 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/StartAndEndTimeFromNexusFileExtractor.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/StartAndEndTimeFromNexusFileExtractor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_STARTANDENDTIMEFROMNEXUSFILEEXTRACTOR_H_
-#define MANTID_DATAHANDLING_STARTANDENDTIMEFROMNEXUSFILEEXTRACTOR_H_
+#pragma once
 
 #include "MantidDataHandling/DllConfig.h"
 #include "MantidKernel/DateAndTime.h"
@@ -21,5 +20,3 @@ Mantid::Types::Core::DateAndTime DLLExport
 extractEndTime(const std::string &filename);
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* MANTID_DATAHANDLING_STARTANDENDTIMEFROMNEXUSFILEEXTRACTOR_H_ */
diff --git a/Framework/DataHandling/inc/MantidDataHandling/UpdateInstrumentFromFile.h b/Framework/DataHandling/inc/MantidDataHandling/UpdateInstrumentFromFile.h
index 9db64738cb1..09ab3265f0f 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/UpdateInstrumentFromFile.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/UpdateInstrumentFromFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_UPDATEINSTRUMENTFROMFILE_H_
-#define MANTID_DATAHANDLING_UPDATEINSTRUMENTFROMFILE_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidGeometry/IDetector.h"
@@ -117,5 +116,3 @@ private:
 
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /*MANTID_DATAHANDLING_UPDATEINSTRUMENTFROMFILE_H_*/
diff --git a/Framework/DataHandling/inc/MantidDataHandling/XmlHandler.h b/Framework/DataHandling/inc/MantidDataHandling/XmlHandler.h
index 9dbad9b2bf7..48629d90a7c 100644
--- a/Framework/DataHandling/inc/MantidDataHandling/XmlHandler.h
+++ b/Framework/DataHandling/inc/MantidDataHandling/XmlHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATAHANDLING_XMLHANDLER_H_
-#define DATAHANDLING_XMLHANDLER_H_
+#pragma once
 
 #include "DllConfig.h"
 
@@ -36,5 +35,3 @@ private:
 };
 } // namespace DataHandling
 } // namespace Mantid
-
-#endif /* DATAHANDLING_XMLHANDLER_H_ */
diff --git a/Framework/DataHandling/src/LoadRaw/isisraw.h b/Framework/DataHandling/src/LoadRaw/isisraw.h
index 4d046942a8a..402e857227b 100644
--- a/Framework/DataHandling/src/LoadRaw/isisraw.h
+++ b/Framework/DataHandling/src/LoadRaw/isisraw.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ISISRAW_H
-#define ISISRAW_H
+#pragma once
 
 /**
   @file isisraw.h ISIS VMS raw file definitions
@@ -385,5 +384,3 @@ public:
   int printInfo(std::ostream &os);
   int getTimeChannels(float *rtcb1, int n);
 };
-
-#endif /* ISISRAW_H */
diff --git a/Framework/DataHandling/src/LoadRaw/isisraw2.h b/Framework/DataHandling/src/LoadRaw/isisraw2.h
index feeed7af3a3..3811f1a494a 100644
--- a/Framework/DataHandling/src/LoadRaw/isisraw2.h
+++ b/Framework/DataHandling/src/LoadRaw/isisraw2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ISISRAW2_H
-#define ISISRAW2_H
+#pragma once
 
 #include "isisraw.h"
 
@@ -27,5 +26,3 @@ private:
   char *outbuff; ///< output buffer
   int m_bufferSize;
 };
-
-#endif /* ISISRAW2_H */
diff --git a/Framework/DataHandling/src/LoadRaw/item_struct.h b/Framework/DataHandling/src/LoadRaw/item_struct.h
index 4f55b9dbe5b..7f3839e1f63 100644
--- a/Framework/DataHandling/src/LoadRaw/item_struct.h
+++ b/Framework/DataHandling/src/LoadRaw/item_struct.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ITEM_STRUCT_H
-#define ITEM_STRUCT_H
+#pragma once
 
 #include <map>
 #include <string>
@@ -80,5 +79,3 @@ public:
   int getArrayItem(const std::string &item_name, int nspec, T *larray);
   int getArrayItem(const std::string &item_name, T *larray);
 };
-
-#endif /* ITEM_STRUCT_H */
diff --git a/Framework/DataHandling/src/LoadRaw/vms_convert.h b/Framework/DataHandling/src/LoadRaw/vms_convert.h
index 56a5acaff24..805465e109a 100644
--- a/Framework/DataHandling/src/LoadRaw/vms_convert.h
+++ b/Framework/DataHandling/src/LoadRaw/vms_convert.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ENDIAN_CONVERT
-#define ENDIAN_CONVERT
+#pragma once
 
 // We aren't going to EVER change this code - so let's ignore the warnings.
 #if defined(__GNUC__) && !(defined(__INTEL_COMPILER))
@@ -42,5 +41,3 @@ void local_to_ieee_float(float *val, const int *n, int *errcode);
 void local_to_ieee_double(double *val, const int *n, int *errcode);
 void ieee_float_to_local(float *val, const int *n, int *errcode);
 void ieee_double_to_local(double *val, const int *n, int *errcode);
-
-#endif /* ENDIAN_CONVERT */
diff --git a/Framework/DataHandling/test/AppendGeometryToSNSNexusTest.h b/Framework/DataHandling/test/AppendGeometryToSNSNexusTest.h
index 83f9b5b216a..b7bff479f0c 100644
--- a/Framework/DataHandling/test/AppendGeometryToSNSNexusTest.h
+++ b/Framework/DataHandling/test/AppendGeometryToSNSNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_APPENDGEOMETRYTOSNSNEXUSTEST_H_
-#define MANTID_DATAHANDLING_APPENDGEOMETRYTOSNSNEXUSTEST_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidKernel/Timer.h"
@@ -74,5 +73,3 @@ public:
     // AnalysisDataService::Instance().remove(outWSName);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_APPENDGEOMETRYTOSNSNEXUSTEST_H_ */
diff --git a/Framework/DataHandling/test/CheckMantidVersionTest.h b/Framework/DataHandling/test/CheckMantidVersionTest.h
index 97ece0341f4..f3ec5cba926 100644
--- a/Framework/DataHandling/test/CheckMantidVersionTest.h
+++ b/Framework/DataHandling/test/CheckMantidVersionTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CHECKMANTIDVERSIONTEST_H_
-#define MANTID_DATAHANDLING_CHECKMANTIDVERSIONTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -142,5 +141,3 @@ public:
   void test_execLocalNewerMajor() { runTest("2.0.2", "v1.11.7", false); }
   void test_execRemoteNewerMajor() { runTest("2.3.7", "v3.0.0", true); }
 };
-
-#endif /* MANTID_DATAHANDLING_CHECKMANTIDVERSIONTEST_H_ */
diff --git a/Framework/DataHandling/test/CompressEventsTest.h b/Framework/DataHandling/test/CompressEventsTest.h
index eb1997ec3a3..1aab4ca4284 100644
--- a/Framework/DataHandling/test/CompressEventsTest.h
+++ b/Framework/DataHandling/test/CompressEventsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef COMPRESSEVENTSTEST_H_
-#define COMPRESSEVENTSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -155,5 +154,3 @@ public:
     doTest("CompressEvents_input", "CompressEvents_input", 0.0, 50, .001);
   }
 };
-
-#endif
diff --git a/Framework/DataHandling/test/CreateChunkingFromInstrumentTest.h b/Framework/DataHandling/test/CreateChunkingFromInstrumentTest.h
index 9673f32fba3..cb84830e255 100644
--- a/Framework/DataHandling/test/CreateChunkingFromInstrumentTest.h
+++ b/Framework/DataHandling/test/CreateChunkingFromInstrumentTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CREATECHUNKINGFROMINSTRUMENTTEST_H_
-#define MANTID_DATAHANDLING_CREATECHUNKINGFROMINSTRUMENTTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -119,5 +118,3 @@ public:
     TS_ASSERT(!alg.isExecuted());
   }
 };
-
-#endif /* MANTID_DATAHANDLING_CREATECHUNKINGFROMINSTRUMENTTEST_H_ */
diff --git a/Framework/DataHandling/test/CreatePolarizationEfficienciesTest.h b/Framework/DataHandling/test/CreatePolarizationEfficienciesTest.h
index 845f039267c..dc4cccab49e 100644
--- a/Framework/DataHandling/test/CreatePolarizationEfficienciesTest.h
+++ b/Framework/DataHandling/test/CreatePolarizationEfficienciesTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_ALGORITHMS_CREATEPOLARIZATIONEFFICIENCIES_TEST_H_
-#define MANTID_ALGORITHMS_CREATEPOLARIZATIONEFFICIENCIES_TEST_H_
+#pragma once
 
 #include "MantidAPI/Axis.h"
 #include "MantidDataHandling/CreatePolarizationEfficiencies.h"
@@ -323,5 +322,3 @@ private:
     return retVal;
   }
 };
-
-#endif /* MANTID_ALGORITHMS_CREATEPOLARIZATIONEFFICIENCIES_TEST_H_ */
diff --git a/Framework/DataHandling/test/CreateSampleShapeTest.h b/Framework/DataHandling/test/CreateSampleShapeTest.h
index ce52a081c26..2ec12a4988c 100644
--- a/Framework/DataHandling/test/CreateSampleShapeTest.h
+++ b/Framework/DataHandling/test/CreateSampleShapeTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef CREATESAMPLESHAPETEST_H_
-#define CREATESAMPLESHAPETEST_H_
+#pragma once
 
 //---------------------------------------
 // Includes
@@ -119,5 +118,3 @@ public:
         Mantid::API::AnalysisDataService::Instance().remove("TestWorkspace"));
   }
 };
-
-#endif
diff --git a/Framework/DataHandling/test/CreateSimulationWorkspaceTest.h b/Framework/DataHandling/test/CreateSimulationWorkspaceTest.h
index 64a86634f7d..29edc1c95e6 100644
--- a/Framework/DataHandling/test/CreateSimulationWorkspaceTest.h
+++ b/Framework/DataHandling/test/CreateSimulationWorkspaceTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_CREATESIMULATIONWORKSPACETEST_H_
-#define MANTID_DATAHANDLING_CREATESIMULATIONWORKSPACETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -261,5 +260,4 @@ private:
   CreateSimulationWorkspace alg;
 
   const std::string outWsName = "outTestWs";
-};
-#endif /* MANTID_DATAHANDLING_CREATESIMULATIONWORKSPACETEST_H_ */
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/DataBlockCompositeTest.h b/Framework/DataHandling/test/DataBlockCompositeTest.h
index 94a8f52237c..5412b5fd8bc 100644
--- a/Framework/DataHandling/test/DataBlockCompositeTest.h
+++ b/Framework/DataHandling/test/DataBlockCompositeTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DATABLOCKCOMPOSITETEST_H_
-#define MANTID_DATAHANDLING_DATABLOCKCOMPOSITETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -1005,5 +1004,3 @@ private:
     return composite;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_DATABLOCKCOMPOSITETEST_H_ */
diff --git a/Framework/DataHandling/test/DataBlockGeneratorTest.h b/Framework/DataHandling/test/DataBlockGeneratorTest.h
index e04d1eb7a6e..c9f2ca5701a 100644
--- a/Framework/DataHandling/test/DataBlockGeneratorTest.h
+++ b/Framework/DataHandling/test/DataBlockGeneratorTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DATABLOCKGENERATORTEST_H_
-#define MANTID_DATAHANDLING_DATABLOCKGENERATORTEST_H_
+#pragma once
 
 #include "MantidDataHandling/DataBlockGenerator.h"
 #include <cxxtest/TestSuite.h>
@@ -114,5 +113,4 @@ private:
                       expectedOutput.size());
     TSM_ASSERT("Should be done", generator.isDone());
   }
-};
-#endif
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/DataBlockTest.h b/Framework/DataHandling/test/DataBlockTest.h
index 308de0d873c..1ab53a84d34 100644
--- a/Framework/DataHandling/test/DataBlockTest.h
+++ b/Framework/DataHandling/test/DataBlockTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DATABLOCKTEST_H_
-#define MANTID_DATAHANDLING_DATABLOCKTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -67,5 +66,3 @@ public:
     TSM_ASSERT("Should not be equal", !(block1 == block2));
   }
 };
-
-#endif /* MANTID_DATAHANDLING_DATABLOCKTEST_H_ */
diff --git a/Framework/DataHandling/test/DefineGaugeVolumeTest.h b/Framework/DataHandling/test/DefineGaugeVolumeTest.h
index 24fd4c21d2e..cb8198a5929 100644
--- a/Framework/DataHandling/test/DefineGaugeVolumeTest.h
+++ b/Framework/DataHandling/test/DefineGaugeVolumeTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DEFINEGAUGEVOLUMETEST_H_
-#define DEFINEGAUGEVOLUMETEST_H_
+#pragma once
 
 #include "MantidDataHandling/DefineGaugeVolume.h"
 #include <cxxtest/TestSuite.h>
@@ -82,5 +81,3 @@ public:
     AnalysisDataService::Instance().remove("EmptyWorkspace");
   }
 };
-
-#endif
diff --git a/Framework/DataHandling/test/DeleteTableRowsTest.h b/Framework/DataHandling/test/DeleteTableRowsTest.h
index e1f41e6172f..32ddd784d13 100644
--- a/Framework/DataHandling/test/DeleteTableRowsTest.h
+++ b/Framework/DataHandling/test/DeleteTableRowsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DELETETABLEROWSTEST_H_
-#define DELETETABLEROWSTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -48,5 +47,3 @@ public:
     AnalysisDataService::Instance().remove(wsName);
   }
 };
-
-#endif /*DELETETABLEROWSTEST_H_*/
diff --git a/Framework/DataHandling/test/DetermineChunkingTest.h b/Framework/DataHandling/test/DetermineChunkingTest.h
index 02e1f181e1a..3e91d68028f 100644
--- a/Framework/DataHandling/test/DetermineChunkingTest.h
+++ b/Framework/DataHandling/test/DetermineChunkingTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DetermineChunkingTEST_H_
-#define MANTID_DATAHANDLING_DetermineChunkingTEST_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidKernel/Timer.h"
@@ -86,5 +85,3 @@ public:
     do_test_CNCS(false);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_DetermineChunkingTEST_H_ */
diff --git a/Framework/DataHandling/test/DownloadFileTest.h b/Framework/DataHandling/test/DownloadFileTest.h
index 591efe1c674..7b0cfe2ac78 100644
--- a/Framework/DataHandling/test/DownloadFileTest.h
+++ b/Framework/DataHandling/test/DownloadFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DOWNLOADFILETEST_H_
-#define MANTID_DATAHANDLING_DOWNLOADFILETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -127,5 +126,3 @@ public:
     TS_ASSERT_EQUALS("HTTPS request succeeded", ss.str());
   }
 };
-
-#endif /* MANTID_DATAHANDLING_DOWNLOADFILETEST_H_ */
diff --git a/Framework/DataHandling/test/DownloadInstrumentTest.h b/Framework/DataHandling/test/DownloadInstrumentTest.h
index 66206743f8b..87cb744d9e8 100644
--- a/Framework/DataHandling/test/DownloadInstrumentTest.h
+++ b/Framework/DataHandling/test/DownloadInstrumentTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_DOWNLOADINSTRUMENTTEST_H_
-#define MANTID_DATAHANDLING_DOWNLOADINSTRUMENTTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -207,5 +206,3 @@ public:
   std::vector<std::string> m_originalInstDir;
   std::vector<Poco::File> m_directoriesToRemove;
 };
-
-#endif /* MANTID_DATAHANDLING_DOWNLOADINSTRUMENTTEST_H_ */
diff --git a/Framework/DataHandling/test/EventWorkspaceCollectionTest.h b/Framework/DataHandling/test/EventWorkspaceCollectionTest.h
index a1df4c30aa1..5434b7d912d 100644
--- a/Framework/DataHandling/test/EventWorkspaceCollectionTest.h
+++ b/Framework/DataHandling/test/EventWorkspaceCollectionTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_EventWorkspaceCollectionTEST_H_
-#define MANTID_DATAHANDLING_EventWorkspaceCollectionTEST_H_
+#pragma once
 
 #include "MantidKernel/TimeSeriesProperty.h"
 
@@ -177,5 +176,3 @@ public:
     }
   }
 };
-
-#endif /* MANTID_DATAHANDLING_EventWorkspaceCollectionTEST_H_ */
diff --git a/Framework/DataHandling/test/ExtractMonitorWorkspaceTest.h b/Framework/DataHandling/test/ExtractMonitorWorkspaceTest.h
index 443f7972a79..9c1ffc5bbc6 100644
--- a/Framework/DataHandling/test/ExtractMonitorWorkspaceTest.h
+++ b/Framework/DataHandling/test/ExtractMonitorWorkspaceTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_EXTRACTMONITORWORKSPACETEST_H_
-#define MANTID_DATAHANDLING_EXTRACTMONITORWORKSPACETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -112,5 +111,3 @@ public:
 private:
   std::string outWSName;
 };
-
-#endif /* MANTID_DATAHANDLING_EXTRACTMONITORWORKSPACETEST_H_ */
diff --git a/Framework/DataHandling/test/ExtractPolarizationEfficienciesTest.h b/Framework/DataHandling/test/ExtractPolarizationEfficienciesTest.h
index 651ee47b3d8..71b64c73d44 100644
--- a/Framework/DataHandling/test/ExtractPolarizationEfficienciesTest.h
+++ b/Framework/DataHandling/test/ExtractPolarizationEfficienciesTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_EXTRACTPOLARIZATIONEFFICIENCIESTEST_H_
-#define MANTID_DATAHANDLING_EXTRACTPOLARIZATIONEFFICIENCIESTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -566,5 +565,3 @@ private:
     return workspace;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_EXTRACTPOLARIZATIONEFFICIENCIESTEST_H_ */
diff --git a/Framework/DataHandling/test/FilterEventsByLogValuePreNexusTest.h b/Framework/DataHandling/test/FilterEventsByLogValuePreNexusTest.h
index 99d7f8a9dc5..97e207d7939 100644
--- a/Framework/DataHandling/test/FilterEventsByLogValuePreNexusTest.h
+++ b/Framework/DataHandling/test/FilterEventsByLogValuePreNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef FILTEREVENTSBYLOGVALUEPRENEXUSTEST_H_
-#define FILTEREVENTSBYLOGVALUEPRENEXUSTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -77,5 +76,3 @@ public:
     TS_ASSERT_THROWS_NOTHING(filteralg.setProperty("CorrectTOFtoSample", true));
   }
 };
-
-#endif /*FILTEREVENTSBYLOGVALUEPRENEXUS_H_*/
diff --git a/Framework/DataHandling/test/FindDetectorsInShapeTest.h b/Framework/DataHandling/test/FindDetectorsInShapeTest.h
index 5f44b10a36e..7a6af438b28 100644
--- a/Framework/DataHandling/test/FindDetectorsInShapeTest.h
+++ b/Framework/DataHandling/test/FindDetectorsInShapeTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef FINDDETECTORSINSHAPETEST_H_
-#define FINDDETECTORSINSHAPETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -157,5 +156,3 @@ private:
   std::string inputFile;
   std::string wsName;
 };
-
-#endif /*FINDDETECTORSINSHAPETEST_H_*/
diff --git a/Framework/DataHandling/test/FindDetectorsParTest.h b/Framework/DataHandling/test/FindDetectorsParTest.h
index 1246d09dac6..a38cf5f8345 100644
--- a/Framework/DataHandling/test/FindDetectorsParTest.h
+++ b/Framework/DataHandling/test/FindDetectorsParTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef FIND_DETECTORSPAR_H_
-#define FIND_DETECTORSPAR_H_
+#pragma once
 
 #include "MantidAPI/FrameworkManager.h"
 #include "MantidAPI/TableRow.h"
@@ -560,4 +559,3 @@ private:
     TSM_ASSERT_EQUALS("azimuthal width wrong ", azw_pattern, bufs[4].str());
   }
 };
-#endif
diff --git a/Framework/DataHandling/test/GenerateGroupingPowderTest.h b/Framework/DataHandling/test/GenerateGroupingPowderTest.h
index e31ea01b906..2efd0f58835 100644
--- a/Framework/DataHandling/test/GenerateGroupingPowderTest.h
+++ b/Framework/DataHandling/test/GenerateGroupingPowderTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_GENERATEGROUPINGPOWDERTEST_H_
-#define MANTID_DATAHANDLING_GENERATEGROUPINGPOWDERTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidDataHandling/GenerateGroupingPowder.h"
@@ -219,5 +218,3 @@ private:
     return filename;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_GENERATEGROUPINGPOWDERTEST_H_ */
diff --git a/Framework/DataHandling/test/GroupDetectors2Test.h b/Framework/DataHandling/test/GroupDetectors2Test.h
index 485fe40093a..b7a8b43b499 100644
--- a/Framework/DataHandling/test/GroupDetectors2Test.h
+++ b/Framework/DataHandling/test/GroupDetectors2Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef GROUPDETECTORS2TEST_H_
-#define GROUPDETECTORS2TEST_H_
+#pragma once
 
 #include "MantidDataHandling/GroupDetectors2.h"
 #include "MantidTestHelpers/ComponentCreationHelper.h"
@@ -1263,5 +1262,3 @@ private:
 
   GroupDetectors2 alg;
 };
-
-#endif /*GROUPDETECTORS2TEST_H_*/
diff --git a/Framework/DataHandling/test/GroupDetectorsTest.h b/Framework/DataHandling/test/GroupDetectorsTest.h
index 1ffbb91ba95..51343f9ac30 100644
--- a/Framework/DataHandling/test/GroupDetectorsTest.h
+++ b/Framework/DataHandling/test/GroupDetectorsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef GROUPDETECTORSTEST_H_
-#define GROUPDETECTORSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -171,5 +170,3 @@ public:
 private:
   GroupDetectors grouper;
 };
-
-#endif /*GROUPDETECTORSTEST_H_*/
diff --git a/Framework/DataHandling/test/H5UtilTest.h b/Framework/DataHandling/test/H5UtilTest.h
index 5b87a93bfb8..119220c21cd 100644
--- a/Framework/DataHandling/test/H5UtilTest.h
+++ b/Framework/DataHandling/test/H5UtilTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_H5UTILTEST_H_
-#define MANTID_DATAHANDLING_H5UTILTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -318,5 +317,3 @@ private:
     }
   }
 };
-
-#endif /* MANTID_DATAHANDLING_H5UTILTEST_H_ */
diff --git a/Framework/DataHandling/test/ISISDataArchiveTest.h b/Framework/DataHandling/test/ISISDataArchiveTest.h
index 5c85051226e..2a89d686f86 100644
--- a/Framework/DataHandling/test/ISISDataArchiveTest.h
+++ b/Framework/DataHandling/test/ISISDataArchiveTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ISISDATAARCHIVETEST_H_
-#define ISISDATAARCHIVETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -180,5 +179,3 @@ public:
     TS_ASSERT_EQUALS(actualResult, "");
   }
 };
-
-#endif /*ISISDATAARCHIVETEST_H_*/
diff --git a/Framework/DataHandling/test/InstrumentRayTracerTest.h b/Framework/DataHandling/test/InstrumentRayTracerTest.h
index bcf49f8ab61..2a3e577d228 100644
--- a/Framework/DataHandling/test/InstrumentRayTracerTest.h
+++ b/Framework/DataHandling/test/InstrumentRayTracerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTRAYTRACERTEST_H_
-#define INSTRUMENTRAYTRACERTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -109,5 +108,3 @@ private:
     std::cout << "\n";
   }
 };
-
-#endif // InstrumentRayTracerTEST_H_
diff --git a/Framework/DataHandling/test/JoinISISPolarizationEfficienciesTest.h b/Framework/DataHandling/test/JoinISISPolarizationEfficienciesTest.h
index a3348a991d8..99b87596d36 100644
--- a/Framework/DataHandling/test/JoinISISPolarizationEfficienciesTest.h
+++ b/Framework/DataHandling/test/JoinISISPolarizationEfficienciesTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_JOINISISPOLARIZATIONEFFICIENCIESTEST_H_
-#define MANTID_DATAHANDLING_JOINISISPOLARIZATIONEFFICIENCIESTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -598,5 +597,3 @@ private:
     return retVal;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_JOINISISPOLARIZATIONEFFICIENCIESTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadAscii2Test.h b/Framework/DataHandling/test/LoadAscii2Test.h
index 2154b18ca91..7feaa017b0a 100644
--- a/Framework/DataHandling/test/LoadAscii2Test.h
+++ b/Framework/DataHandling/test/LoadAscii2Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADASCIITEST_H_
-#define LOADASCIITEST_H_
+#pragma once
 
 #include "MantidDataHandling/LoadAscii2.h"
 #include "SaveAscii2Test.h"
@@ -714,5 +713,3 @@ private:
     filename = save.getPropertyValue("Filename");
   }
 };
-
-#endif // LOADASCIITEST_H_
diff --git a/Framework/DataHandling/test/LoadAsciiStlTest.h b/Framework/DataHandling/test/LoadAsciiStlTest.h
index febe2edb304..96e1e2d6ee5 100644
--- a/Framework/DataHandling/test/LoadAsciiStlTest.h
+++ b/Framework/DataHandling/test/LoadAsciiStlTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOAD_ASCIISTL_TEST_H_
-#define LOAD_ASCIISTL_TEST_H_
+#pragma once
 
 #include "MantidAPI/FileFinder.h"
 #include "MantidDataHandling/LoadAsciiStl.h"
@@ -83,5 +82,3 @@ private:
   }
   const ScaleUnits units = ScaleUnits::metres;
 };
-
-#endif /* LOAD_ASCIISTL_TEST_H_ */
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadAsciiTest.h b/Framework/DataHandling/test/LoadAsciiTest.h
index aec7302a1d3..4a3d84cba65 100644
--- a/Framework/DataHandling/test/LoadAsciiTest.h
+++ b/Framework/DataHandling/test/LoadAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADASCIITEST_H_
-#define LOADASCIITEST_H_
+#pragma once
 
 #include "MantidDataHandling/LoadAscii.h"
 #include "cxxtest/TestSuite.h"
@@ -312,5 +311,3 @@ private:
     }
   }
 };
-
-#endif // LOADASCIITEST_H_
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadBBYTest.h b/Framework/DataHandling/test/LoadBBYTest.h
index f5e04d40e1d..e9e55b71bcd 100644
--- a/Framework/DataHandling/test/LoadBBYTest.h
+++ b/Framework/DataHandling/test/LoadBBYTest.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef LOADMCSTASTEST_H_
-#define LOADMCSTASTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -181,5 +180,3 @@ public:
     TS_ASSERT_LESS_THAN(0.0399999, minTime);
   }
 };
-
-#endif /*LoadBBYTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadBinaryStlTest.h b/Framework/DataHandling/test/LoadBinaryStlTest.h
index f87e0b6cee8..2915fd793f2 100644
--- a/Framework/DataHandling/test/LoadBinaryStlTest.h
+++ b/Framework/DataHandling/test/LoadBinaryStlTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOAD_BINARYSTL_TEST_H_
-#define LOAD_BINARYSTL_TEST_H_
+#pragma once
 #include "MantidAPI/FileFinder.h"
 #include "MantidDataHandling/LoadBinaryStl.h"
 #include "MantidGeometry/Objects/MeshObject.h"
@@ -89,5 +88,4 @@ private:
   }
 
   const ScaleUnits units = ScaleUnits::metres;
-};
-#endif /* LOAD_BINARYSTL_TEST_H_ */
\ No newline at end of file
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadCalFileTest.h b/Framework/DataHandling/test/LoadCalFileTest.h
index 4a09ac4e5b8..66c5b0e9a91 100644
--- a/Framework/DataHandling/test/LoadCalFileTest.h
+++ b/Framework/DataHandling/test/LoadCalFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADCALFILETEST_H_
-#define MANTID_DATAHANDLING_LOADCALFILETEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/Run.h"
@@ -162,5 +161,3 @@ private:
     return loadAlg;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADCALFILETEST_H_ */
diff --git a/Framework/DataHandling/test/LoadCanSAS1dTest.h b/Framework/DataHandling/test/LoadCanSAS1dTest.h
index 0597730ec96..db4cedf7a37 100644
--- a/Framework/DataHandling/test/LoadCanSAS1dTest.h
+++ b/Framework/DataHandling/test/LoadCanSAS1dTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADCANSAS1DTEST_H
-#define LOADCANSAS1DTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -238,5 +237,3 @@ const double LoadCanSAS1dTest::es808[] = {
     0.153269,  0.141219,  0.13289,   0.130725,  0.123281,  0.11705,
     0.104102,  0.0991949, 0.0933884, 0.082556,  0.0757769, 0.0715806,
     0.0674828, 0.064006,  0.0600373, 0.0581645, 0.0766164};
-
-#endif
diff --git a/Framework/DataHandling/test/LoadDAETest.h b/Framework/DataHandling/test/LoadDAETest.h
index 2ad2dc28d0f..cb6cd3bd816 100644
--- a/Framework/DataHandling/test/LoadDAETest.h
+++ b/Framework/DataHandling/test/LoadDAETest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADDAETEST_H_
-#define LOADDAETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -32,5 +31,3 @@ public:
         "LoadDAE is deprecated (on 2013-04-22). Use StartLiveData instead.");
   }
 };
-
-#endif /*LOADDAETEST_H_*/
diff --git a/Framework/DataHandling/test/LoadDaveGrpTest.h b/Framework/DataHandling/test/LoadDaveGrpTest.h
index 5dc43a1a032..a580b0b378f 100644
--- a/Framework/DataHandling/test/LoadDaveGrpTest.h
+++ b/Framework/DataHandling/test/LoadDaveGrpTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADDAVEGRPTEST_H_
-#define LOADDAVEGRPTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/Axis.h"
@@ -98,5 +97,3 @@ public:
     }
   }
 };
-
-#endif // LOADDAVEGRPTEST_H_
diff --git a/Framework/DataHandling/test/LoadDetectorInfoTest.h b/Framework/DataHandling/test/LoadDetectorInfoTest.h
index d9d0e1a0d7b..a8909db12b5 100644
--- a/Framework/DataHandling/test/LoadDetectorInfoTest.h
+++ b/Framework/DataHandling/test/LoadDetectorInfoTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADDETECTORINFOTEST_H_
-#define LOADDETECTORINFOTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -457,5 +456,3 @@ private:
   std::string m_testfile;
   std::string m_wsName;
 };
-
-#endif /*LOADDETECTORINFOTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadDetectorsGroupingFileTest.h b/Framework/DataHandling/test/LoadDetectorsGroupingFileTest.h
index c0d09b42f7a..c213f76a3d7 100644
--- a/Framework/DataHandling/test/LoadDetectorsGroupingFileTest.h
+++ b/Framework/DataHandling/test/LoadDetectorsGroupingFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADDETECTORSGROUPINGFILETEST_H_
-#define MANTID_DATAHANDLING_LOADDETECTORSGROUPINGFILETEST_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidKernel/Timer.h"
@@ -467,5 +466,3 @@ public:
     TS_ASSERT_EQUALS(gws->getNumberHistograms(), 32);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADDETECTORSGROUPINGFILETEST_H_ */
diff --git a/Framework/DataHandling/test/LoadDiffCalTest.h b/Framework/DataHandling/test/LoadDiffCalTest.h
index 278fcb855ef..6df1b26d6a3 100644
--- a/Framework/DataHandling/test/LoadDiffCalTest.h
+++ b/Framework/DataHandling/test/LoadDiffCalTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADDIFFCALTEST_H_
-#define MANTID_DATAHANDLING_LOADDIFFCALTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -161,5 +160,3 @@ public:
       Poco::File(groupingfile).remove();
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADDIFFCALTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadDspacemapTest.h b/Framework/DataHandling/test/LoadDspacemapTest.h
index 15515bd4d39..7c8abd8070d 100644
--- a/Framework/DataHandling/test/LoadDspacemapTest.h
+++ b/Framework/DataHandling/test/LoadDspacemapTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADDSPACEMAPTEST_H_
-#define MANTID_DATAHANDLING_LOADDSPACEMAPTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidDataHandling/LoadDspacemap.h"
@@ -95,5 +94,3 @@ public:
     doTestVulcan("pid_offset_vulcan_new.dat.bin", "VULCAN-Binary");
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADDSPACEMAPTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadEMUauTest.h b/Framework/DataHandling/test/LoadEMUauTest.h
index 86c16e69bec..c4fabc01c4b 100644
--- a/Framework/DataHandling/test/LoadEMUauTest.h
+++ b/Framework/DataHandling/test/LoadEMUauTest.h
@@ -1,6 +1,5 @@
 
-#ifndef LOADEMUAUTEST_H_
-#define LOADEMUAUTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -93,5 +92,3 @@ public:
     TS_ASSERT_DELTA(iparam("SampleAnalyser"), 1.8, 1.0e-3);
   }
 };
-
-#endif /*LOADEMUAUTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadEmptyInstrumentTest.h b/Framework/DataHandling/test/LoadEmptyInstrumentTest.h
index 7ccbe4e87a3..ecf044d2e22 100644
--- a/Framework/DataHandling/test/LoadEmptyInstrumentTest.h
+++ b/Framework/DataHandling/test/LoadEmptyInstrumentTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADEMPTYINSTRUMENTTEST_H_
-#define LOADEMPTYINSTRUMENTTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -1114,5 +1113,3 @@ private:
   std::string inputFile;
   std::string wsName;
 };
-
-#endif /*LOADEMPTYINSTRUMENTTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadEventNexusIndexSetupTest.h b/Framework/DataHandling/test/LoadEventNexusIndexSetupTest.h
index 89b791b43a1..59c3920f5be 100644
--- a/Framework/DataHandling/test/LoadEventNexusIndexSetupTest.h
+++ b/Framework/DataHandling/test/LoadEventNexusIndexSetupTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADEVENTNEXUSINDEXSETUPTEST_H_
-#define MANTID_DATAHANDLING_LOADEVENTNEXUSINDEXSETUPTEST_H_
+#pragma once
 
 #include "MantidTestHelpers/FakeObjects.h"
 #include <cxxtest/TestSuite.h>
@@ -367,5 +366,3 @@ public:
 private:
   MatrixWorkspace_sptr m_ws;
 };
-
-#endif /* MANTID_DATAHANDLING_LOADEVENTNEXUSINDEXSETUPTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadEventNexusTest.h b/Framework/DataHandling/test/LoadEventNexusTest.h
index e46d7c81b4d..228a491444b 100644
--- a/Framework/DataHandling/test/LoadEventNexusTest.h
+++ b/Framework/DataHandling/test/LoadEventNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADEVENTNEXUSTEST_H_
-#define LOADEVENTNEXUSTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -1116,5 +1115,3 @@ public:
     TS_ASSERT(loader.execute());
   }
 };
-
-#endif /*LOADEVENTNEXUSTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadEventPreNexus2Test.h b/Framework/DataHandling/test/LoadEventPreNexus2Test.h
index a736050a075..2e046e128e8 100644
--- a/Framework/DataHandling/test/LoadEventPreNexus2Test.h
+++ b/Framework/DataHandling/test/LoadEventPreNexus2Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADEVENTPRENEXUSTEST_H_
-#define LOADEVENTPRENEXUSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -310,5 +309,3 @@ public:
     TS_ASSERT(loader.execute());
   }
 };
-
-#endif /* LOADEVENTPRENEXUSTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadFITSTest.h b/Framework/DataHandling/test/LoadFITSTest.h
index 15799804046..aa6f05f7bc9 100644
--- a/Framework/DataHandling/test/LoadFITSTest.h
+++ b/Framework/DataHandling/test/LoadFITSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADFITSTEST_H_
-#define MANTID_DATAHANDLING_LOADFITSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -458,5 +457,3 @@ public:
     TS_ASSERT(lf.execute());
   }
 };
-
-#endif // MANTID_DATAHANDLING_LOADFITSTEST_H_
diff --git a/Framework/DataHandling/test/LoadFullprofResolutionTest.h b/Framework/DataHandling/test/LoadFullprofResolutionTest.h
index f3497394303..1bbfed94e84 100644
--- a/Framework/DataHandling/test/LoadFullprofResolutionTest.h
+++ b/Framework/DataHandling/test/LoadFullprofResolutionTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADFULLPROFRESOLUTIONTEST_H_
-#define MANTID_DATAHANDLING_LOADFULLPROFRESOLUTIONTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -1177,5 +1176,3 @@ public:
 private:
   std::string wsName; // For Workspace property
 };
-
-#endif /* MANTID_DATAHANDLING_LOADFULLPROFRESOLUTIONTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadGSASInstrumentFileTest.h b/Framework/DataHandling/test/LoadGSASInstrumentFileTest.h
index fdad1f4afcf..8b8ea9147fb 100644
--- a/Framework/DataHandling/test/LoadGSASInstrumentFileTest.h
+++ b/Framework/DataHandling/test/LoadGSASInstrumentFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADGSASINSTRUMENTFILETEST_H_
-#define MANTID_DATAHANDLING_LOADGSASINSTRUMENTFILETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -527,5 +526,3 @@ public:
 private:
   std::string wsName; // For workspace property
 };
-
-#endif /* MANTID_DATAHANDLING_LOADGSASINSTRUMENTFILETEST_H_ */
diff --git a/Framework/DataHandling/test/LoadGSSTest.h b/Framework/DataHandling/test/LoadGSSTest.h
index 4c844d16823..66aa280e96b 100644
--- a/Framework/DataHandling/test/LoadGSSTest.h
+++ b/Framework/DataHandling/test/LoadGSSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADGSSTEST_H_
-#define LOADGSSTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -216,5 +215,4 @@ private:
     loadAlg->setRethrows(true);
     return loadAlg;
   }
-};
-#endif // LOADGSSTEST_H_
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadHFIRSANSTest.h b/Framework/DataHandling/test/LoadHFIRSANSTest.h
index 970d0f0792e..e35f166f774 100644
--- a/Framework/DataHandling/test/LoadHFIRSANSTest.h
+++ b/Framework/DataHandling/test/LoadHFIRSANSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LoadHFIRSANSTEST_H
-#define LoadHFIRSANSTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -218,5 +217,4 @@ public:
 
 private:
   std::string inputFile;
-};
-#endif
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadIDFFromNexusTest.h b/Framework/DataHandling/test/LoadIDFFromNexusTest.h
index 8d50824272c..86b4a7c51e3 100644
--- a/Framework/DataHandling/test/LoadIDFFromNexusTest.h
+++ b/Framework/DataHandling/test/LoadIDFFromNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADINSTRUMENTTESTFROMRAW_H_
-#define LOADINSTRUMENTTESTFROMRAW_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -455,5 +454,3 @@ private:
   std::string inputFile;
   std::string wsName;
 };
-
-#endif /*LOADINSTRUMENTTESTFROMRAW_H_*/
diff --git a/Framework/DataHandling/test/LoadILLDiffractionTest.h b/Framework/DataHandling/test/LoadILLDiffractionTest.h
index 7b3e33df9a5..a93a1ac4335 100644
--- a/Framework/DataHandling/test/LoadILLDiffractionTest.h
+++ b/Framework/DataHandling/test/LoadILLDiffractionTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLDIFFRACTIONTEST_H_
-#define MANTID_DATAHANDLING_LOADILLDIFFRACTIONTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -488,5 +487,3 @@ public:
 private:
   LoadILLDiffraction m_alg;
 };
-
-#endif /* MANTID_DATAHANDLING_LOADILLDIFFRACTIONTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadILLIndirect2Test.h b/Framework/DataHandling/test/LoadILLIndirect2Test.h
index f778c8cee20..9b04ad1f4b0 100644
--- a/Framework/DataHandling/test/LoadILLIndirect2Test.h
+++ b/Framework/DataHandling/test/LoadILLIndirect2Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLINDIRECT2TEST_H_
-#define MANTID_DATAHANDLING_LOADILLINDIRECT2TEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -164,5 +163,3 @@ private:
     return loader;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADILLINDIRECT2TEST_H_ */
diff --git a/Framework/DataHandling/test/LoadILLPolarizationFactorsTest.h b/Framework/DataHandling/test/LoadILLPolarizationFactorsTest.h
index 8da70044c44..25d0b1fb4b0 100644
--- a/Framework/DataHandling/test/LoadILLPolarizationFactorsTest.h
+++ b/Framework/DataHandling/test/LoadILLPolarizationFactorsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLPOLARIZATIONFACTORSTEST_H_
-#define MANTID_DATAHANDLING_LOADILLPOLARIZATIONFACTORSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -229,5 +228,3 @@ public:
     }
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADILLPOLARIZATIONFACTORSTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadILLReflectometryTest.h b/Framework/DataHandling/test/LoadILLReflectometryTest.h
index 16c47d12920..b1c9cd5b4fc 100644
--- a/Framework/DataHandling/test/LoadILLReflectometryTest.h
+++ b/Framework/DataHandling/test/LoadILLReflectometryTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLREFLECTOMETRYTEST_H_
-#define MANTID_DATAHANDLING_LOADILLREFLECTOMETRYTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -779,5 +778,3 @@ private:
     return loader;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADILLREFLECTOMETRYTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadILLSANSTest.h b/Framework/DataHandling/test/LoadILLSANSTest.h
index 89bcd122c50..46d7b6214cd 100644
--- a/Framework/DataHandling/test/LoadILLSANSTest.h
+++ b/Framework/DataHandling/test/LoadILLSANSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLSANSTEST_H_
-#define MANTID_DATAHANDLING_LOADILLSANSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -281,5 +280,3 @@ public:
 private:
   LoadILLSANS m_alg;
 };
-
-#endif /* MANTID_DATAHANDLING_LOADILLSANSTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadILLTOF2Test.h b/Framework/DataHandling/test/LoadILLTOF2Test.h
index 24c7dcd227e..af8c635b512 100644
--- a/Framework/DataHandling/test/LoadILLTOF2Test.h
+++ b/Framework/DataHandling/test/LoadILLTOF2Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADILLTOF2TEST_H_
-#define LOADILLTOF2TEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -243,5 +242,3 @@ public:
 private:
   std::string m_dataFile;
 };
-
-#endif /*LOADILLTOF2TEST_H_*/
diff --git a/Framework/DataHandling/test/LoadILLTest.h b/Framework/DataHandling/test/LoadILLTest.h
index 5930f13d441..2fa6ef09668 100644
--- a/Framework/DataHandling/test/LoadILLTest.h
+++ b/Framework/DataHandling/test/LoadILLTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADILLTEST_H_
-#define MANTID_DATAHANDLING_LOADILLTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -91,5 +90,3 @@ public:
     checkLoader("ILL/Figaro/000002", "LoadILLReflectometry");
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADILLTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadISISNexusTest.h b/Framework/DataHandling/test/LoadISISNexusTest.h
index 605cfae3892..4c691e3351c 100644
--- a/Framework/DataHandling/test/LoadISISNexusTest.h
+++ b/Framework/DataHandling/test/LoadISISNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADISISNEXUSTEST_H_
-#define LOADISISNEXUSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -1665,5 +1664,3 @@ public:
     TS_ASSERT(loader.execute());
   }
 };
-
-#endif /*LOADISISNEXUSTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadISISPolarizationEfficienciesTest.h b/Framework/DataHandling/test/LoadISISPolarizationEfficienciesTest.h
index 40292126ff9..fc554962b7a 100644
--- a/Framework/DataHandling/test/LoadISISPolarizationEfficienciesTest.h
+++ b/Framework/DataHandling/test/LoadISISPolarizationEfficienciesTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADISISPOLARIZATIONEFFICIENCIESTEST_H_
-#define MANTID_DATAHANDLING_LOADISISPOLARIZATIONEFFICIENCIESTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -165,5 +164,3 @@ private:
                             "3.30000,1.000000,0.00993287\n"
                             "4.50000,1.000000,0.00668106\n"};
 };
-
-#endif /* MANTID_DATAHANDLING_LOADISISPOLARIZATIONEFFICIENCIESTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadInstrumentFromNexusTest.h b/Framework/DataHandling/test/LoadInstrumentFromNexusTest.h
index 784e11cc01b..028d5813634 100644
--- a/Framework/DataHandling/test/LoadInstrumentFromNexusTest.h
+++ b/Framework/DataHandling/test/LoadInstrumentFromNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADINSTRUMENTFROMNEXUS_H_
-#define LOADINSTRUMENTFROMNEXUS_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -84,5 +83,3 @@ private:
     TS_ASSERT(alg.isExecuted());
   }
 };
-
-#endif /*LOADINSTRUMENTFROMNEXUS_H_*/
diff --git a/Framework/DataHandling/test/LoadInstrumentFromRawTest.h b/Framework/DataHandling/test/LoadInstrumentFromRawTest.h
index 4e88eabb87f..914a76005b2 100644
--- a/Framework/DataHandling/test/LoadInstrumentFromRawTest.h
+++ b/Framework/DataHandling/test/LoadInstrumentFromRawTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADINSTRUMENTTESTFROMRAW_H_
-#define LOADINSTRUMENTTESTFROMRAW_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -116,5 +115,3 @@ private:
   std::string inputFile;
   std::string wsName;
 };
-
-#endif /*LOADINSTRUMENTTESTFROMRAW_H_*/
diff --git a/Framework/DataHandling/test/LoadInstrumentTest.h b/Framework/DataHandling/test/LoadInstrumentTest.h
index 9d5ee155417..8263e32e057 100644
--- a/Framework/DataHandling/test/LoadInstrumentTest.h
+++ b/Framework/DataHandling/test/LoadInstrumentTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADINSTRUMENTTEST_H_
-#define LOADINSTRUMENTTEST_H_
+#pragma once
 
 #include "MantidAPI/Axis.h"
 #include "MantidAPI/ExperimentInfo.h"
@@ -948,5 +947,3 @@ public:
 
   void test_SNAP() { doTest("SNAP_Definition.xml", 1); }
 };
-
-#endif /*LOADINSTRUMENTTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadIsawDetCalTest.h b/Framework/DataHandling/test/LoadIsawDetCalTest.h
index 07218c7281f..2ef508bb91b 100644
--- a/Framework/DataHandling/test/LoadIsawDetCalTest.h
+++ b/Framework/DataHandling/test/LoadIsawDetCalTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DIFFRACTIONEVENTREADDETCALTEST_H_
-#define DIFFRACTIONEVENTREADDETCALTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -195,5 +194,3 @@ private:
   const std::string inputFile = "SNAP_34172_low.DetCal, SNAP_34172_high.DetCal";
   const std::string wsName = "testSNAP";
 };
-
-#endif /*DIFFRACTIONEVENTREADDETCALTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadLLBTest.h b/Framework/DataHandling/test/LoadLLBTest.h
index 4eb3dbf64e6..31d1b88277b 100644
--- a/Framework/DataHandling/test/LoadLLBTest.h
+++ b/Framework/DataHandling/test/LoadLLBTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADLLBTEST_H_
-#define MANTID_DATAHANDLING_LOADLLBTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -106,5 +105,4 @@ private:
     loader->setRethrows(true);
     return loader;
   }
-};
-#endif /* MANTID_DATAHANDLING_LOADLLBTEST_H_ */
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadLogTest.h b/Framework/DataHandling/test/LoadLogTest.h
index 2a3935a1c7f..c2812d8f294 100644
--- a/Framework/DataHandling/test/LoadLogTest.h
+++ b/Framework/DataHandling/test/LoadLogTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADLOGTEST_H_
-#define LOADLOGTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -314,5 +313,3 @@ private:
   std::string outputSpace;
   std::string inputSpace;
 };
-
-#endif /*LOADLOGTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadMLZTest.h b/Framework/DataHandling/test/LoadMLZTest.h
index c31e874af5b..7107779ba7c 100644
--- a/Framework/DataHandling/test/LoadMLZTest.h
+++ b/Framework/DataHandling/test/LoadMLZTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADMLZTEST_H_
-#define LOADMLZTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -100,5 +99,3 @@ private:
   Mantid::DataHandling::LoadMLZ loader;
   std::string m_dataFile;
 };
-
-#endif /*LoadMLZTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadMappingTableTest.h b/Framework/DataHandling/test/LoadMappingTableTest.h
index 3709ace829a..907b640facf 100644
--- a/Framework/DataHandling/test/LoadMappingTableTest.h
+++ b/Framework/DataHandling/test/LoadMappingTableTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADMAPPINGTABLETEST_H_
-#define LOADMAPPINGTABLETEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -94,5 +93,4 @@ private:
   std::string inputFile;
   std::string outputSpace;
   MatrixWorkspace_sptr work1;
-};
-#endif /*LOADMAPPINGTABLETEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadMaskTest.h b/Framework/DataHandling/test/LoadMaskTest.h
index d9d860485b4..9b68071bbe3 100644
--- a/Framework/DataHandling/test/LoadMaskTest.h
+++ b/Framework/DataHandling/test/LoadMaskTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADMASKTEST_H_
-#define MANTID_DATAHANDLING_LOADMASKTEST_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidKernel/Timer.h"
@@ -607,5 +606,3 @@ public:
 private:
   LoadMask loadFile;
 };
-
-#endif /* MANTID_DATAHANDLING_LOADMASKINGFILETEST_H_ */
diff --git a/Framework/DataHandling/test/LoadMcStasNexusTest.h b/Framework/DataHandling/test/LoadMcStasNexusTest.h
index fdf8a151d96..3b856f9d3c1 100644
--- a/Framework/DataHandling/test/LoadMcStasNexusTest.h
+++ b/Framework/DataHandling/test/LoadMcStasNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADMCSTASNEXUSTEST_H_
-#define LOADMCSTASNEXUSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -111,5 +110,4 @@ private:
   LoadMcStasNexus loadMcStasNexusAlg;
   std::string inputFile;
   std::string outputSpace;
-};
-#endif /*LOADMCSTASNEXUSTEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadMcStasTest.h b/Framework/DataHandling/test/LoadMcStasTest.h
index 9d1cfc97033..82f354c36db 100644
--- a/Framework/DataHandling/test/LoadMcStasTest.h
+++ b/Framework/DataHandling/test/LoadMcStasTest.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef LOADMCSTASTEST_H_
-#define LOADMCSTASTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -225,5 +224,3 @@ public:
 private:
   LoadMcStas loadFile;
 };
-
-#endif /*LoadMcStasTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadMuonLogTest.h b/Framework/DataHandling/test/LoadMuonLogTest.h
index 7a837547e68..9ae6a1b0142 100644
--- a/Framework/DataHandling/test/LoadMuonLogTest.h
+++ b/Framework/DataHandling/test/LoadMuonLogTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADMUONLOGTEST_H_
-#define LOADMUONLOGTEST_H_
+#pragma once
 
 // These includes seem to make the difference between initialization of the
 // workspace names (workspace2D/1D etc), instrument classes and not for this
@@ -98,5 +97,4 @@ private:
   std::string inputFile;
   std::string outputSpace;
   std::string inputSpace;
-};
-#endif /*LOADMUONLOGTEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadMuonNexus1Test.h b/Framework/DataHandling/test/LoadMuonNexus1Test.h
index 975b99ef501..faf0615ea1b 100644
--- a/Framework/DataHandling/test/LoadMuonNexus1Test.h
+++ b/Framework/DataHandling/test/LoadMuonNexus1Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADMUONNEXUS1TEST_H_
-#define LOADMUONNEXUS1TEST_H_
+#pragma once
 
 // These includes seem to make the difference between initialization of the
 // workspace names (workspace2D/1D etc), instrument classes and not for this
@@ -1047,5 +1046,3 @@ public:
 private:
   LoadMuonNexus1 loader;
 };
-
-#endif /*LOADMUONNEXUS1TEST_H_*/
diff --git a/Framework/DataHandling/test/LoadMuonNexus2Test.h b/Framework/DataHandling/test/LoadMuonNexus2Test.h
index afac49784af..f528f96203c 100644
--- a/Framework/DataHandling/test/LoadMuonNexus2Test.h
+++ b/Framework/DataHandling/test/LoadMuonNexus2Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADMUONNEXUS2TEST_H_
-#define LOADMUONNEXUS2TEST_H_
+#pragma once
 
 // These includes seem to make the difference between initialization of the
 // workspace names (workspace2D/1D etc), instrument classes and not for this
@@ -491,5 +490,3 @@ public:
 private:
   LoadMuonNexus2 loader;
 };
-
-#endif /*LOADMUONNEXUS2TEST_H_*/
diff --git a/Framework/DataHandling/test/LoadMuonNexusTest.h b/Framework/DataHandling/test/LoadMuonNexusTest.h
index 599a5c430da..cb67f1f54cb 100644
--- a/Framework/DataHandling/test/LoadMuonNexusTest.h
+++ b/Framework/DataHandling/test/LoadMuonNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADMUONNEXUSTEST_H_
-#define LOADMUONNEXUSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -17,5 +16,3 @@ class LoadMuonNexusTest : public CxxTest::TestSuite {
 public:
   void testExec() {}
 };
-
-#endif /*LOADMUONNEXUSTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadNGEMTest.h b/Framework/DataHandling/test/LoadNGEMTest.h
index b465a46c2e9..ba6e07e92c9 100644
--- a/Framework/DataHandling/test/LoadNGEMTest.h
+++ b/Framework/DataHandling/test/LoadNGEMTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADNGEMTEST_H_
-#define LOADNGEMTEST_H_
+#pragma once
 
 #include <MantidAPI/AnalysisDataService.h>
 #include <MantidAPI/FileFinder.h>
@@ -201,5 +200,3 @@ private:
     return filepath;
   }
 };
-
-#endif // LOADNGEMTEST_H_
diff --git a/Framework/DataHandling/test/LoadNXSPETest.h b/Framework/DataHandling/test/LoadNXSPETest.h
index 3d75f47f8f1..6f97817c40b 100644
--- a/Framework/DataHandling/test/LoadNXSPETest.h
+++ b/Framework/DataHandling/test/LoadNXSPETest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNXSPETEST_H_
-#define MANTID_DATAHANDLING_LOADNXSPETEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -68,5 +67,3 @@ public:
     TS_ASSERT(good_confidence > no_confidence);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADNXSPETEST_H_ */
diff --git a/Framework/DataHandling/test/LoadNXcanSASTest.h b/Framework/DataHandling/test/LoadNXcanSASTest.h
index fd8baad407b..5291bdea121 100644
--- a/Framework/DataHandling/test/LoadNXcanSASTest.h
+++ b/Framework/DataHandling/test/LoadNXcanSASTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNXCANSASTEST_H_
-#define MANTID_DATAHANDLING_LOADNXCANSASTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -601,5 +600,4 @@ private:
 
     alg2D.setPropertyValue("OutputWorkspace", outWsName);
   }
-};
-#endif /* MANTID_DATAHANDLING_LOADNXCANSASTEST_H_ */
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadNexusLogsTest.h b/Framework/DataHandling/test/LoadNexusLogsTest.h
index e49f1fc4c43..0c2cabbf0c2 100644
--- a/Framework/DataHandling/test/LoadNexusLogsTest.h
+++ b/Framework/DataHandling/test/LoadNexusLogsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADNEXUSLOGSTEST_H_
-#define LOADNEXUSLOGSTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -299,5 +298,3 @@ private:
     return WorkspaceFactory::Instance().create("Workspace2D", 1, 1, 1);
   }
 };
-
-#endif /* LOADNEXUSLOGS_H_*/
diff --git a/Framework/DataHandling/test/LoadNexusMonitorsTest.h b/Framework/DataHandling/test/LoadNexusMonitorsTest.h
index f4b0c013a9b..a824d5e3298 100644
--- a/Framework/DataHandling/test/LoadNexusMonitorsTest.h
+++ b/Framework/DataHandling/test/LoadNexusMonitorsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADNEXUSMONITORSTEST_H_
-#define LOADNEXUSMONITORSTEST_H_
+#pragma once
 
 #include "MantidAPI/FrameworkManager.h"
 #include "MantidAPI/Run.h"
@@ -372,5 +371,3 @@ private:
   LoadNexusMonitors ld;
   LoadNexusMonitors2 ld2;
 };
-
-#endif /*LOADNEXUSMONITORSTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadNexusProcessed2Test.h b/Framework/DataHandling/test/LoadNexusProcessed2Test.h
index 50622570ef4..d233ecfe376 100644
--- a/Framework/DataHandling/test/LoadNexusProcessed2Test.h
+++ b/Framework/DataHandling/test/LoadNexusProcessed2Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADNEXUSPROCESSED2TEST_H_
-#define MANTID_DATAHANDLING_LOADNEXUSPROCESSED2TEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -310,5 +309,3 @@ public:
     TS_ASSERT(!wsOut->detectorInfo().isEquivalent(wsIn->detectorInfo()));
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADNEXUSPROCESSED2TEST_H_ */
diff --git a/Framework/DataHandling/test/LoadNexusProcessedTest.h b/Framework/DataHandling/test/LoadNexusProcessedTest.h
index 39dbbc8f813..5a43a2046be 100644
--- a/Framework/DataHandling/test/LoadNexusProcessedTest.h
+++ b/Framework/DataHandling/test/LoadNexusProcessedTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADNEXUSPROCESSEDTEST_H_
-#define LOADNEXUSPROCESSEDTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -1461,5 +1460,3 @@ public:
     TS_ASSERT(loader.execute());
   }
 };
-
-#endif /*LOADNEXUSPROCESSEDTESTRAW_H_*/
diff --git a/Framework/DataHandling/test/LoadNexusTest.h b/Framework/DataHandling/test/LoadNexusTest.h
index 5a75fce8a23..a2a28f08e82 100644
--- a/Framework/DataHandling/test/LoadNexusTest.h
+++ b/Framework/DataHandling/test/LoadNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADNEXUSTEST_H_
-#define LOADNEXUSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -143,5 +142,3 @@ private:
   std::string inputFile;
   std::string outputSpace;
 };
-
-#endif /*LOADNEXUSTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadPDFgetNFileTest.h b/Framework/DataHandling/test/LoadPDFgetNFileTest.h
index 72433c114a8..d305b1a9524 100644
--- a/Framework/DataHandling/test/LoadPDFgetNFileTest.h
+++ b/Framework/DataHandling/test/LoadPDFgetNFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADPDFGETNFILETEST_H_
-#define MANTID_DATAHANDLING_LOADPDFGETNFILETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -120,5 +119,3 @@ public:
     return;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADPDFGETNFILETEST_H_ */
diff --git a/Framework/DataHandling/test/LoadPLNTest.h b/Framework/DataHandling/test/LoadPLNTest.h
index 98f3862a5b5..564dd534236 100644
--- a/Framework/DataHandling/test/LoadPLNTest.h
+++ b/Framework/DataHandling/test/LoadPLNTest.h
@@ -1,5 +1,4 @@
-#ifndef LOADPLNTEST_H_
-#define LOADPLNTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -135,5 +134,3 @@ public:
     TS_ASSERT_DELTA(logpm("SampleRotation"), 13.001, 1.0e-3);
   }
 };
-
-#endif /*LOADPLNTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadPSIMuonBinTest.h b/Framework/DataHandling/test/LoadPSIMuonBinTest.h
index ad2e4ab4c4c..45b3ae72f56 100644
--- a/Framework/DataHandling/test/LoadPSIMuonBinTest.h
+++ b/Framework/DataHandling/test/LoadPSIMuonBinTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADPSIMUONBINTEST_H_
-#define MANTID_DATAHANDLING_LOADPSIMUONBINTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -196,5 +195,3 @@ private:
     return filepath;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADPSIMUONBINTEST_H_ */
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadParameterFileTest.h b/Framework/DataHandling/test/LoadParameterFileTest.h
index 2cbc7505b9e..5f2665851f4 100644
--- a/Framework/DataHandling/test/LoadParameterFileTest.h
+++ b/Framework/DataHandling/test/LoadParameterFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADPARAMETERFILETEST_H_
-#define LOADPARAMETERFILETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -239,5 +238,3 @@ private:
   std::string inputFile;
   std::string wsName;
 };
-
-#endif /*LOADPARAMETERFILETEST_H_*/
diff --git a/Framework/DataHandling/test/LoadPreNexusMonitorsTest.h b/Framework/DataHandling/test/LoadPreNexusMonitorsTest.h
index 77735d416d9..b32a79c5c21 100644
--- a/Framework/DataHandling/test/LoadPreNexusMonitorsTest.h
+++ b/Framework/DataHandling/test/LoadPreNexusMonitorsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADPRENEXUSMONITORSTEST_H_
-#define LOADPRENEXUSMONITORSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -76,5 +75,3 @@ private:
   Mantid::DataHandling::LoadPreNexusMonitors loader;
   std::string runinfoFile;
 };
-
-#endif /* LOADPRENEXUSMONITORSTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadPreNexusTest.h b/Framework/DataHandling/test/LoadPreNexusTest.h
index 9118d74536f..b7c27437420 100644
--- a/Framework/DataHandling/test/LoadPreNexusTest.h
+++ b/Framework/DataHandling/test/LoadPreNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADPRENEXUSTEST_H_
-#define MANTID_DATAHANDLING_LOADPRENEXUSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -68,5 +67,3 @@ public:
     AnalysisDataService::Instance().remove(outWSName);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADPRENEXUSTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadQKKTest.h b/Framework/DataHandling/test/LoadQKKTest.h
index 60558501020..1003fe6a1d2 100644
--- a/Framework/DataHandling/test/LoadQKKTest.h
+++ b/Framework/DataHandling/test/LoadQKKTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADQKKTEST_H_
-#define LOADQKKTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/SpectrumInfo.h"
@@ -74,5 +73,3 @@ public:
     }
   }
 };
-
-#endif // LOADQKKTEST_H_
diff --git a/Framework/DataHandling/test/LoadRKHTest.h b/Framework/DataHandling/test/LoadRKHTest.h
index e7ea85e46eb..780a70a3af4 100644
--- a/Framework/DataHandling/test/LoadRKHTest.h
+++ b/Framework/DataHandling/test/LoadRKHTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADRKHTEST_H_
-#define LOADRKHTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/Axis.h"
@@ -370,5 +369,3 @@ private:
     file.close();
   }
 };
-
-#endif // LOADRKHTEST_H_
diff --git a/Framework/DataHandling/test/LoadRaw3Test.h b/Framework/DataHandling/test/LoadRaw3Test.h
index 9b0032e63db..44ed9b419dc 100644
--- a/Framework/DataHandling/test/LoadRaw3Test.h
+++ b/Framework/DataHandling/test/LoadRaw3Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LoadRaw3TEST_H_
-#define LoadRaw3TEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/Axis.h"
@@ -1231,5 +1230,3 @@ public:
     TS_ASSERT(loader.execute());
   }
 };
-
-#endif /*LoadRaw3TEST_H_*/
diff --git a/Framework/DataHandling/test/LoadRawBin0Test.h b/Framework/DataHandling/test/LoadRawBin0Test.h
index 65b913b3645..6a098125181 100644
--- a/Framework/DataHandling/test/LoadRawBin0Test.h
+++ b/Framework/DataHandling/test/LoadRawBin0Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LoadRawBin0Test123_H_
-#define LoadRawBin0Test123_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -175,5 +174,3 @@ private:
   std::string inputFile;
   std::string outputSpace;
 };
-
-#endif /*LoadRawBin0Test_H_*/
diff --git a/Framework/DataHandling/test/LoadRawSaveNxsLoadNxsTest.h b/Framework/DataHandling/test/LoadRawSaveNxsLoadNxsTest.h
index 5067ae6b14e..dfb363245ae 100644
--- a/Framework/DataHandling/test/LoadRawSaveNxsLoadNxsTest.h
+++ b/Framework/DataHandling/test/LoadRawSaveNxsLoadNxsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADRAWSAVENXSLOADNXSTEST_H_
-#define LOADRAWSAVENXSLOADNXSTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/Axis.h"
@@ -235,5 +234,3 @@ private:
   std::string outputSpace;
   std::string outputFile;
 };
-
-#endif /* LOADRAWSAVENXSLOADNXSTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadRawSpectrum0Test.h b/Framework/DataHandling/test/LoadRawSpectrum0Test.h
index fae42744e5f..c2baba38295 100644
--- a/Framework/DataHandling/test/LoadRawSpectrum0Test.h
+++ b/Framework/DataHandling/test/LoadRawSpectrum0Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LoadRawSpectrum0Test_H_
-#define LoadRawSpectrum0Test_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -169,5 +168,3 @@ private:
   std::string inputFile;
   std::string outputSpace;
 };
-
-#endif /*LoadRawSpectrum0Test_H_*/
diff --git a/Framework/DataHandling/test/LoadSESANSTest.h b/Framework/DataHandling/test/LoadSESANSTest.h
index 00722d4b612..4a4bc4ffbcd 100644
--- a/Framework/DataHandling/test/LoadSESANSTest.h
+++ b/Framework/DataHandling/test/LoadSESANSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSESANSTEST_H_
-#define MANTID_DATAHANDLING_LOADSESANSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -115,5 +114,3 @@ private:
 
   LoadSESANS testAlg;
 };
-
-#endif /* MANTID_DATAHANDLING_LOADSESANSTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadSINQFocusTest.h b/Framework/DataHandling/test/LoadSINQFocusTest.h
index ec292846861..30d2bbdbfb7 100644
--- a/Framework/DataHandling/test/LoadSINQFocusTest.h
+++ b/Framework/DataHandling/test/LoadSINQFocusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSINQTEST_H_
-#define MANTID_DATAHANDLING_LOADSINQTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -65,5 +64,3 @@ public:
 private:
   std::string m_testFile;
 };
-
-#endif /* MANTID_DATAHANDLING_LOADSINQTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadSNSNexusTest.h b/Framework/DataHandling/test/LoadSNSNexusTest.h
index 18e059038ef..fd8b636cb30 100644
--- a/Framework/DataHandling/test/LoadSNSNexusTest.h
+++ b/Framework/DataHandling/test/LoadSNSNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADSNSNEXUSTEST_H_
-#define LOADSNSNEXUSTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -112,5 +111,3 @@ public:
     // TS_ASSERT_EQUALS(ws->sample().getName(),"NONE");
   }
 };
-
-#endif /*LOADSNSNEXUSTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadSNSspecTest.h b/Framework/DataHandling/test/LoadSNSspecTest.h
index 55e048213a1..6505003b5e3 100644
--- a/Framework/DataHandling/test/LoadSNSspecTest.h
+++ b/Framework/DataHandling/test/LoadSNSspecTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADSNSSPECTEST_H_
-#define LOADSNSSPECTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -114,5 +113,3 @@ public:
 private:
   Mantid::DataHandling::LoadSNSspec loader;
 };
-
-#endif /*LoadSNSSPECTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadSPETest.h b/Framework/DataHandling/test/LoadSPETest.h
index 11ab2661208..c97dd8f796e 100644
--- a/Framework/DataHandling/test/LoadSPETest.h
+++ b/Framework/DataHandling/test/LoadSPETest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADSPETEST_H_
-#define LOADSPETEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/Axis.h"
@@ -90,5 +89,3 @@ public:
 private:
   Mantid::DataHandling::LoadSPE loader;
 };
-
-#endif /*LoadSPETEST_H_*/
diff --git a/Framework/DataHandling/test/LoadSampleDetailsFromRawTest.h b/Framework/DataHandling/test/LoadSampleDetailsFromRawTest.h
index 54885ac9fc2..f69d170502f 100644
--- a/Framework/DataHandling/test/LoadSampleDetailsFromRawTest.h
+++ b/Framework/DataHandling/test/LoadSampleDetailsFromRawTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADSAMPLEDETAILSFROMRAWTEST_H_
-#define LOADSAMPLEDETAILSFROMRAWTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -71,5 +70,3 @@ private:
     TS_ASSERT(alg.isExecuted());
   }
 };
-
-#endif /*LOADSAMPLEDETAILSFROMRAWTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadSampleEnvironmentTest.h b/Framework/DataHandling/test/LoadSampleEnvironmentTest.h
index 4c82e4388b0..a85e19ea9e4 100644
--- a/Framework/DataHandling/test/LoadSampleEnvironmentTest.h
+++ b/Framework/DataHandling/test/LoadSampleEnvironmentTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOAD_ENVIRONMENTEST_H_
-#define LOAD_ENVIRONMENTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/FileFinder.h"
@@ -111,5 +110,3 @@ private:
     return cube;
   }
 };
-
-#endif /* LOAD_ENVIRONMENTTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadSampleShapeTest.h b/Framework/DataHandling/test/LoadSampleShapeTest.h
index e58ea987aac..bcd5e660083 100644
--- a/Framework/DataHandling/test/LoadSampleShapeTest.h
+++ b/Framework/DataHandling/test/LoadSampleShapeTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOAD_SHAPETEST_H_
-#define LOAD_SHAPETEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/FileFinder.h"
@@ -288,5 +287,4 @@ private:
     loadAlg->setRethrows(true);
     return loadAlg;
   }
-};
-#endif /* LOAD_SHAPETEST_H_ */
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadSassenaTest.h b/Framework/DataHandling/test/LoadSassenaTest.h
index 62d1bbbd270..b7d4dcefea2 100644
--- a/Framework/DataHandling/test/LoadSassenaTest.h
+++ b/Framework/DataHandling/test/LoadSassenaTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSASSENATEST_H_
-#define MANTID_DATAHANDLING_LOADSASSENATEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/WorkspaceGroup.h"
@@ -98,5 +97,3 @@ private:
   Mantid::DataHandling::LoadSassena m_alg;
 
 }; // end of class LoadSassenaTest
-
-#endif // MANTID_DATAHANDLING_LOADSASSENATEST_H_
diff --git a/Framework/DataHandling/test/LoadSaveAsciiTest.h b/Framework/DataHandling/test/LoadSaveAsciiTest.h
index 637184c2c42..05c4cd2b46f 100644
--- a/Framework/DataHandling/test/LoadSaveAsciiTest.h
+++ b/Framework/DataHandling/test/LoadSaveAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADSAVEASCIITEST_H_
-#define LOADSAVEASCIITEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -91,5 +90,3 @@ public:
     Poco::File(filename).remove();
   }
 };
-
-#endif /*LOADSAVEASCIITEST_H_*/
diff --git a/Framework/DataHandling/test/LoadSpecTest.h b/Framework/DataHandling/test/LoadSpecTest.h
index 2fdab530b67..3d0a3cb098b 100644
--- a/Framework/DataHandling/test/LoadSpecTest.h
+++ b/Framework/DataHandling/test/LoadSpecTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADSNSSPECTEST_H_
-#define LOADSNSSPECTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -104,5 +103,3 @@ public:
 private:
   Mantid::DataHandling::LoadSpec loader;
 };
-
-#endif /*LoadSNSSPECTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadSpice2dTest.h b/Framework/DataHandling/test/LoadSpice2dTest.h
index 51bc27170d0..7f0acac4d8a 100644
--- a/Framework/DataHandling/test/LoadSpice2dTest.h
+++ b/Framework/DataHandling/test/LoadSpice2dTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADSPICE2DTEST_H
-#define LOADSPICE2DTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -246,5 +245,4 @@ public:
 private:
   std::string inputFile;
   Mantid::DataHandling::LoadSpice2D spice2d;
-};
-#endif
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadSpiceAsciiTest.h b/Framework/DataHandling/test/LoadSpiceAsciiTest.h
index 9862a95a87e..4cfee433ed9 100644
--- a/Framework/DataHandling/test/LoadSpiceAsciiTest.h
+++ b/Framework/DataHandling/test/LoadSpiceAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSPICEASCIITEST_H_
-#define MANTID_DATAHANDLING_LOADSPICEASCIITEST_H_
+#pragma once
 
 #include "MantidDataHandling/LoadSpiceAscii.h"
 #include <cxxtest/TestSuite.h>
@@ -178,5 +177,3 @@ public:
     TS_ASSERT(!testalg.isExecuted());
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADSPICEASCIITEST_H_ */
diff --git a/Framework/DataHandling/test/LoadSpiceXML2DDetTest.h b/Framework/DataHandling/test/LoadSpiceXML2DDetTest.h
index 34dfa080d17..e41e36beb7c 100644
--- a/Framework/DataHandling/test/LoadSpiceXML2DDetTest.h
+++ b/Framework/DataHandling/test/LoadSpiceXML2DDetTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSPICEXML2DDETTEST_H_
-#define MANTID_DATAHANDLING_LOADSPICEXML2DDETTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -745,5 +744,3 @@ public:
     return datatablews;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADSPICEXML2DDETTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadStlTest.h b/Framework/DataHandling/test/LoadStlTest.h
index d3752f7b48c..670dc417e33 100644
--- a/Framework/DataHandling/test/LoadStlTest.h
+++ b/Framework/DataHandling/test/LoadStlTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOAD_STL_TEST_H_
-#define LOAD_STL_TEST_H_
+#pragma once
 #include "MantidDataHandling/LoadStl.h"
 #include "MantidGeometry/Objects/MeshObject.h"
 #include "MantidKernel/V3D.h"
@@ -71,5 +70,4 @@ public:
     TS_ASSERT_DIFFERS(HashV3DPair{}(pair2), HashV3DPair{}(pair3));
     TS_ASSERT_DIFFERS(HashV3DPair{}(pair1), HashV3DPair{}(pair3));
   }
-};
-#endif /* LOAD_STL_TEST_H_ */
\ No newline at end of file
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/LoadSwansTest.h b/Framework/DataHandling/test/LoadSwansTest.h
index 6240f7ab030..f1ce11d74b5 100644
--- a/Framework/DataHandling/test/LoadSwansTest.h
+++ b/Framework/DataHandling/test/LoadSwansTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADSWANSTEST_H_
-#define MANTID_DATAHANDLING_LOADSWANSTEST_H_
+#pragma once
 
 #include "MantidAPI/Run.h"
 #include "MantidDataHandling/LoadSwans.h"
@@ -76,5 +75,3 @@ public:
         outputWS->run().getPropertyValueAsType<double>("wavelength"), 3.5);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_LOADSWANSTEST_H_ */
diff --git a/Framework/DataHandling/test/LoadTBLTest.h b/Framework/DataHandling/test/LoadTBLTest.h
index 7230989f652..08b723dd30f 100644
--- a/Framework/DataHandling/test/LoadTBLTest.h
+++ b/Framework/DataHandling/test/LoadTBLTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADTBLTEST_H_
-#define LOADTBLTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -402,5 +401,3 @@ private:
     TS_ASSERT_THROWS_NOTHING(Poco::File(m_abspath).remove());
   }
 };
-
-#endif // LOADTBLTEST_H_
diff --git a/Framework/DataHandling/test/LoadTOFRawNexusTest.h b/Framework/DataHandling/test/LoadTOFRawNexusTest.h
index 38f83ef651f..9b229c327f9 100644
--- a/Framework/DataHandling/test/LoadTOFRawNexusTest.h
+++ b/Framework/DataHandling/test/LoadTOFRawNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADTOFRAWNEXUSTEST_H_
-#define LOADTOFRAWNEXUSTEST_H_
+#pragma once
 
 #include "MantidDataHandling/LoadTOFRawNexus.h"
 
@@ -275,5 +274,3 @@ public:
     TS_ASSERT(loader.execute());
   }
 };
-
-#endif /*LOADTOFRAWNEXUSTEST_H_*/
diff --git a/Framework/DataHandling/test/LoadTest.h b/Framework/DataHandling/test/LoadTest.h
index a24581987a9..b7ef50b9f1f 100644
--- a/Framework/DataHandling/test/LoadTest.h
+++ b/Framework/DataHandling/test/LoadTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOADTEST_H_
-#define LOADTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -364,5 +363,3 @@ public:
     }
   }
 };
-
-#endif /*LOADTEST_H_*/
diff --git a/Framework/DataHandling/test/MaskDetectorsInShapeTest.h b/Framework/DataHandling/test/MaskDetectorsInShapeTest.h
index 7cd274a36a6..9a6cac9aa9b 100644
--- a/Framework/DataHandling/test/MaskDetectorsInShapeTest.h
+++ b/Framework/DataHandling/test/MaskDetectorsInShapeTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MARKDEADDETECTORSINSHAPETEST_H_
-#define MARKDEADDETECTORSINSHAPETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -161,5 +160,4 @@ public:
 
     AnalysisDataService::Instance().remove(workspace);
   }
-};
-#endif /*MARKDEADDETECTORSINSHAPETEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/MaskDetectorsTest.h b/Framework/DataHandling/test/MaskDetectorsTest.h
index 3aa29b96412..9258e4f7859 100644
--- a/Framework/DataHandling/test/MaskDetectorsTest.h
+++ b/Framework/DataHandling/test/MaskDetectorsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MARKDEADDETECTORSTEST_H_
-#define MARKDEADDETECTORSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -822,5 +821,3 @@ public:
 private:
   MaskDetectors marker;
 };
-
-#endif /*MARKDEADDETECTORSTEST_H_*/
diff --git a/Framework/DataHandling/test/MaskSpectraTest.h b/Framework/DataHandling/test/MaskSpectraTest.h
index 5b4b45250da..da35a4c6537 100644
--- a/Framework/DataHandling/test/MaskSpectraTest.h
+++ b/Framework/DataHandling/test/MaskSpectraTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_MASKSPECTRATEST_H_
-#define MANTID_DATAHANDLING_MASKSPECTRATEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -127,5 +126,3 @@ public:
     TS_ASSERT_EQUALS(spectrumInfo.isMasked(3), true);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_MASKSPECTRATEST_H_ */
diff --git a/Framework/DataHandling/test/MeshFileIOTest.h b/Framework/DataHandling/test/MeshFileIOTest.h
index ebf640ff103..77ac5a8ebb3 100644
--- a/Framework/DataHandling/test/MeshFileIOTest.h
+++ b/Framework/DataHandling/test/MeshFileIOTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LOAD_SHAPETEST_H_
-#define LOAD_SHAPETEST_H_
+#pragma once
 
 #include "MantidAPI/FileFinder.h"
 #include "MantidDataHandling/LoadBinaryStl.h"
@@ -161,5 +160,3 @@ private:
     }
   }
 };
-
-#endif
\ No newline at end of file
diff --git a/Framework/DataHandling/test/ModifyDetectorDotDatFileTest.h b/Framework/DataHandling/test/ModifyDetectorDotDatFileTest.h
index 129e2471472..db4395595c9 100644
--- a/Framework/DataHandling/test/ModifyDetectorDotDatFileTest.h
+++ b/Framework/DataHandling/test/ModifyDetectorDotDatFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_MODIFYDETECTORDOTDAYFILETEST_H_
-#define MANTID_DATAHANDLING_MODIFYDETECTORDOTDAYFILETEST_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidKernel/Timer.h"
@@ -136,5 +135,3 @@ public:
     Poco::File(fullFilename).remove();
   }
 };
-
-#endif /* MANTID_DATAHANDLING_MODIFYDETECTORDOTDAYFILETEST_H_ */
diff --git a/Framework/DataHandling/test/MoveInstrumentComponentTest.h b/Framework/DataHandling/test/MoveInstrumentComponentTest.h
index 6ff50b75352..d06d56d1706 100644
--- a/Framework/DataHandling/test/MoveInstrumentComponentTest.h
+++ b/Framework/DataHandling/test/MoveInstrumentComponentTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MOVEINSTRUMENTCOMPONENTTEST_H_
-#define MOVEINSTRUMENTCOMPONENTTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -146,5 +145,3 @@ private:
   boost::shared_ptr<Instrument> instrument;
   MatrixWorkspace_sptr WS;
 };
-
-#endif /*MOVEINSTRUMENTCOMPONENTTEST_H_*/
diff --git a/Framework/DataHandling/test/NXcanSASTestHelper.h b/Framework/DataHandling/test/NXcanSASTestHelper.h
index 979bd7b7ab7..208a518af2a 100644
--- a/Framework/DataHandling/test/NXcanSASTestHelper.h
+++ b/Framework/DataHandling/test/NXcanSASTestHelper.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLINGTEST_NXCANSASTESTHELPER_H
-#define MANTID_DATAHANDLINGTEST_NXCANSASTESTHELPER_H
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace_fwd.h"
 #include <Poco/TemporaryFile.h>
@@ -121,5 +120,4 @@ provide2DWorkspace(NXcanSASTestParameters &parameters);
 void set2DValues(Mantid::API::MatrixWorkspace_sptr ws);
 
 void removeFile(std::string filename);
-} // namespace NXcanSASTestHelper
-#endif
+} // namespace NXcanSASTestHelper
\ No newline at end of file
diff --git a/Framework/DataHandling/test/NexusTesterTest.h b/Framework/DataHandling/test/NexusTesterTest.h
index 62d4017ace1..b6faa1dcf55 100644
--- a/Framework/DataHandling/test/NexusTesterTest.h
+++ b/Framework/DataHandling/test/NexusTesterTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_NEXUSTESTERTEST_H_
-#define MANTID_DATAHANDLING_NEXUSTESTERTEST_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidKernel/Timer.h"
@@ -55,5 +54,3 @@ public:
     TS_ASSERT_LESS_THAN(0.0, LoadSpeed);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_NEXUSTESTERTEST_H_ */
diff --git a/Framework/DataHandling/test/ORNLDataArchiveTest.h b/Framework/DataHandling/test/ORNLDataArchiveTest.h
index a9bdff128de..c2eeba4b342 100644
--- a/Framework/DataHandling/test/ORNLDataArchiveTest.h
+++ b/Framework/DataHandling/test/ORNLDataArchiveTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ORNLDATAARCHIVETEST_H_
-#define ORNLDATAARCHIVETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -144,5 +143,3 @@ public:
     TS_ASSERT(arch);
   }
 };
-
-#endif // ORNLDATAARCHIVETEST_H_
diff --git a/Framework/DataHandling/test/PDLoadCharacterizationsTest.h b/Framework/DataHandling/test/PDLoadCharacterizationsTest.h
index d7b09ee9ef1..d4c8195d86a 100644
--- a/Framework/DataHandling/test/PDLoadCharacterizationsTest.h
+++ b/Framework/DataHandling/test/PDLoadCharacterizationsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_LOADPDCHARACTERIZATIONSTEST_H_
-#define MANTID_DATAHANDLING_LOADPDCHARACTERIZATIONSTEST_H_
+#pragma once
 
 #include <boost/shared_ptr.hpp>
 #include <cxxtest/TestSuite.h>
@@ -473,5 +472,3 @@ public:
   }
   */
 };
-
-#endif /* MANTID_DATAHANDLING_LOADPDCHARACTERIZATIONSTEST_H_ */
diff --git a/Framework/DataHandling/test/PrecompiledHeader.h b/Framework/DataHandling/test/PrecompiledHeader.h
index 619dc343fa4..01998fafe5c 100644
--- a/Framework/DataHandling/test/PrecompiledHeader.h
+++ b/Framework/DataHandling/test/PrecompiledHeader.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLINGTEST_PRECOMPILED_HEADER_H_
-#define MANTID_DATAHANDLINGTEST_PRECOMPILED_HEADER_H_
+#pragma once
 
 // cxxtest
 #include <cxxtest/WrappedTestSuite.h>
@@ -17,5 +16,3 @@
 #include <set>
 #include <string>
 #include <vector>
-
-#endif // MANTID_DATAHANDLINGTEST_PRECOMPILED_HEADER_H_
\ No newline at end of file
diff --git a/Framework/DataHandling/test/RawFileInfoTest.h b/Framework/DataHandling/test/RawFileInfoTest.h
index b6a772a0b42..db90b36c467 100644
--- a/Framework/DataHandling/test/RawFileInfoTest.h
+++ b/Framework/DataHandling/test/RawFileInfoTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef RAWFILEINFOTEST_H_
-#define RAWFILEINFOTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/ITableWorkspace.h"
@@ -135,5 +134,3 @@ private:
   // buildserver)
   const std::string m_filetotest;
 };
-
-#endif
diff --git a/Framework/DataHandling/test/RemoveLogsTest.h b/Framework/DataHandling/test/RemoveLogsTest.h
index 52a674bfc9d..eae8f6d8452 100644
--- a/Framework/DataHandling/test/RemoveLogsTest.h
+++ b/Framework/DataHandling/test/RemoveLogsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REMOVELOGSTEST_H_
-#define REMOVELOGSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -163,5 +162,3 @@ private:
   RemoveLogs m_remover;
   std::string m_sampleWorkspace;
 };
-
-#endif /*REMOVELOGSTEST_H_*/
diff --git a/Framework/DataHandling/test/RenameLogTest.h b/Framework/DataHandling/test/RenameLogTest.h
index 79da18f9978..3ad646c3272 100644
--- a/Framework/DataHandling/test/RenameLogTest.h
+++ b/Framework/DataHandling/test/RenameLogTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_RENAMELOGTEST_H_
-#define MANTID_DATAHANDLING_RENAMELOGTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -148,5 +147,3 @@ private:
   std::vector<Types::Core::DateAndTime> m_rawTimes;
   std::vector<double> m_rawValues;
 };
-
-#endif /* MANTID_DATAHANDLING_RENAMELOGTEST_H_ */
diff --git a/Framework/DataHandling/test/RotateInstrumentComponentTest.h b/Framework/DataHandling/test/RotateInstrumentComponentTest.h
index e07e026cd69..917664f79ee 100644
--- a/Framework/DataHandling/test/RotateInstrumentComponentTest.h
+++ b/Framework/DataHandling/test/RotateInstrumentComponentTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ROTATEINSTRUMENTCOMPONENTTEST_H_
-#define MANTID_DATAHANDLING_ROTATEINSTRUMENTCOMPONENTTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -104,5 +103,3 @@ private:
     return testWS;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_ROTATEINSTRUMENTCOMPONENTTEST_H_ */
diff --git a/Framework/DataHandling/test/RotateSourceTest.h b/Framework/DataHandling/test/RotateSourceTest.h
index 2dc5a59d5ad..5625b837f0a 100644
--- a/Framework/DataHandling/test/RotateSourceTest.h
+++ b/Framework/DataHandling/test/RotateSourceTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_ROTATESOURCETEST_H_
-#define MANTID_DATAHANDLING_ROTATESOURCETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -191,5 +190,3 @@ public:
     TS_ASSERT_DELTA(newPos.Z(), 1.0, 1E-5);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_ROTATESOURCETEST_H_ */
diff --git a/Framework/DataHandling/test/SampleEnvironmentFactoryTest.h b/Framework/DataHandling/test/SampleEnvironmentFactoryTest.h
index 5b4362eca0f..54989dbd17a 100644
--- a/Framework/DataHandling/test/SampleEnvironmentFactoryTest.h
+++ b/Framework/DataHandling/test/SampleEnvironmentFactoryTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAMPLEENVIRONMENTFACTORYTEST_H_
-#define MANTID_DATAHANDLING_SAMPLEENVIRONMENTFACTORYTEST_H_
+#pragma once
 
 #include "MantidDataHandling/SampleEnvironmentFactory.h"
 #include "MantidGeometry/Instrument/Container.h"
@@ -114,5 +113,3 @@ private:
     }
   };
 };
-
-#endif /* MANTID_DATAHANDLING_SAMPLEENVIRONMENTFACTORYTEST_H_ */
diff --git a/Framework/DataHandling/test/SampleEnvironmentSpecFileFinderTest.h b/Framework/DataHandling/test/SampleEnvironmentSpecFileFinderTest.h
index 6473c24a165..4ffa11066f7 100644
--- a/Framework/DataHandling/test/SampleEnvironmentSpecFileFinderTest.h
+++ b/Framework/DataHandling/test/SampleEnvironmentSpecFileFinderTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECFILEFINDERTEST_H
-#define MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECFILEFINDERTEST_H
+#pragma once
 
 #include "MantidDataHandling/SampleEnvironmentFactory.h"
 #include <cxxtest/TestSuite.h>
@@ -142,5 +141,3 @@ private:
   const std::string m_envName = "TestingEnv";
   const std::string m_badName = "BadEnv";
 };
-
-#endif // MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECFILEFINDERTEST_H
diff --git a/Framework/DataHandling/test/SampleEnvironmentSpecParserTest.h b/Framework/DataHandling/test/SampleEnvironmentSpecParserTest.h
index 92846ea1cfe..a043183b4c2 100644
--- a/Framework/DataHandling/test/SampleEnvironmentSpecParserTest.h
+++ b/Framework/DataHandling/test/SampleEnvironmentSpecParserTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECPARSERTEST_H_
-#define MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECPARSERTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -492,5 +491,3 @@ private:
     return parser.parse(name, "", instream);
   }
 };
-
-#endif /* MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECPARSERTEST_H_ */
diff --git a/Framework/DataHandling/test/SampleEnvironmentSpecTest.h b/Framework/DataHandling/test/SampleEnvironmentSpecTest.h
index c091fedda7d..c51a1eb2e49 100644
--- a/Framework/DataHandling/test/SampleEnvironmentSpecTest.h
+++ b/Framework/DataHandling/test/SampleEnvironmentSpecTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECTEST_H_
-#define MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -108,5 +107,3 @@ public:
                      const std::invalid_argument &);
   }
 };
-
-#endif /* MANTID_GEOMETRY_SAMPLEENVIRONMENTSPECTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveANSTOAsciiTest.h b/Framework/DataHandling/test/SaveANSTOAsciiTest.h
index 5c24ba29409..3ee6ca51d41 100644
--- a/Framework/DataHandling/test/SaveANSTOAsciiTest.h
+++ b/Framework/DataHandling/test/SaveANSTOAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEANSTOASCIITEST_H_
-#define SAVEANSTOASCIITEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -230,5 +229,3 @@ private:
   std::string m_filename, m_name, m_long_filename;
   std::vector<double> m_dataX, m_dataY, m_dataE;
 };
-
-#endif /*SAVEANSTOTEST_H_*/
diff --git a/Framework/DataHandling/test/SaveAscii2Test.h b/Framework/DataHandling/test/SaveAscii2Test.h
index 7631fce85b1..5d646f4c961 100644
--- a/Framework/DataHandling/test/SaveAscii2Test.h
+++ b/Framework/DataHandling/test/SaveAscii2Test.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEASCIITEST_H_
-#define SAVEASCIITEST_H_
+#pragma once
 
 #include "MantidAPI/Axis.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -1047,5 +1046,4 @@ private:
         l2, polar, azimutal, nBins);
     AnalysisDataService::Instance().add(m_name, wsToSave);
   }
-};
-#endif /*SAVEASCIITEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SaveAsciiTest.h b/Framework/DataHandling/test/SaveAsciiTest.h
index 9de6e378b4a..10de218915c 100644
--- a/Framework/DataHandling/test/SaveAsciiTest.h
+++ b/Framework/DataHandling/test/SaveAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEASCIITEST_H_
-#define SAVEASCIITEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -165,5 +164,3 @@ public:
     AnalysisDataService::Instance().remove(WSname);
   }
 };
-
-#endif /*SAVEASCIITEST_H_*/
diff --git a/Framework/DataHandling/test/SaveBankScatteringAnglesTest.h b/Framework/DataHandling/test/SaveBankScatteringAnglesTest.h
index e6d658925c3..da2f92c5e88 100644
--- a/Framework/DataHandling/test/SaveBankScatteringAnglesTest.h
+++ b/Framework/DataHandling/test/SaveBankScatteringAnglesTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEBANKSCATTERINGANGLESTEST_H_
-#define MANTID_DATAHANDLING_SAVEBANKSCATTERINGANGLESTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -118,5 +117,3 @@ private:
     groupAlg->execute();
   }
 };
-
-#endif // MANTID_DATAHANDLING_SAVEBANKSCATTERINGANGLESTEST_H_
diff --git a/Framework/DataHandling/test/SaveCSVTest.h b/Framework/DataHandling/test/SaveCSVTest.h
index 04e0ab2d170..749b80f8ce0 100644
--- a/Framework/DataHandling/test/SaveCSVTest.h
+++ b/Framework/DataHandling/test/SaveCSVTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVECSVTEST_H_
-#define SAVECSVTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/WorkspaceFactory.h"
@@ -265,5 +264,3 @@ private:
     stream.close();
   }
 };
-
-#endif /*SAVECSVTEST_H_*/
diff --git a/Framework/DataHandling/test/SaveCalFileTest.h b/Framework/DataHandling/test/SaveCalFileTest.h
index 53fcaf4a7bd..29bf4eb9554 100644
--- a/Framework/DataHandling/test/SaveCalFileTest.h
+++ b/Framework/DataHandling/test/SaveCalFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVECALFILETEST_H_
-#define MANTID_DATAHANDLING_SAVECALFILETEST_H_
+#pragma once
 
 #include "MantidAPI/SpectrumInfo.h"
 #include "MantidDataHandling/LoadInstrument.h"
@@ -89,5 +88,3 @@ public:
       Poco::File(filename).remove();
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVECALFILETEST_H_ */
diff --git a/Framework/DataHandling/test/SaveCanSAS1dTest.h b/Framework/DataHandling/test/SaveCanSAS1dTest.h
index 85a6034dfe9..363f891be4d 100644
--- a/Framework/DataHandling/test/SaveCanSAS1dTest.h
+++ b/Framework/DataHandling/test/SaveCanSAS1dTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVECANSAS1DTEST_H
-#define SAVECANSAS1DTEST_H
+#pragma once
 #include <cxxtest/TestSuite.h>
 
 #include "MantidAPI/Axis.h"
@@ -276,5 +275,3 @@ private:
   std::string m_runNum;
   MatrixWorkspace_sptr ws;
 };
-
-#endif
diff --git a/Framework/DataHandling/test/SaveCanSAS1dTest2.h b/Framework/DataHandling/test/SaveCanSAS1dTest2.h
index 23d7628862c..af23d1e4c21 100644
--- a/Framework/DataHandling/test/SaveCanSAS1dTest2.h
+++ b/Framework/DataHandling/test/SaveCanSAS1dTest2.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVECANSAS1D2TEST_H
-#define SAVECANSAS1D2TEST_H
+#pragma once
 #include <cxxtest/TestSuite.h>
 
 #include "MantidAPI/Axis.h"
@@ -388,5 +387,3 @@ private:
   std::string m_runNum;
   MatrixWorkspace_sptr ws;
 };
-
-#endif
diff --git a/Framework/DataHandling/test/SaveDaveGrpTest.h b/Framework/DataHandling/test/SaveDaveGrpTest.h
index 8c702bf26a7..307f27d592b 100644
--- a/Framework/DataHandling/test/SaveDaveGrpTest.h
+++ b/Framework/DataHandling/test/SaveDaveGrpTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDAVEGRPTEST_H_
-#define MANTID_DATAHANDLING_SAVEDAVEGRPTEST_H_
+#pragma once
 
 #include "MantidDataHandling/SaveDaveGrp.h"
 #include "MantidTestHelpers/WorkspaceCreationHelper.h"
@@ -281,5 +280,3 @@ private:
     return inputWS;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEDAVEGRPTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveDetectorsGroupingTest.h b/Framework/DataHandling/test/SaveDetectorsGroupingTest.h
index e05d9560bcc..afd64124b1c 100644
--- a/Framework/DataHandling/test/SaveDetectorsGroupingTest.h
+++ b/Framework/DataHandling/test/SaveDetectorsGroupingTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDETECTORSGROUPINGTEST_H_
-#define MANTID_DATAHANDLING_SAVEDETECTORSGROUPINGTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/Run.h"
@@ -151,5 +150,3 @@ public:
     file.remove();
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEDETECTORSGROUPINGTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveDiffCalTest.h b/Framework/DataHandling/test/SaveDiffCalTest.h
index 6825892872f..748689f9985 100644
--- a/Framework/DataHandling/test/SaveDiffCalTest.h
+++ b/Framework/DataHandling/test/SaveDiffCalTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDIFFCALTEST_H_
-#define MANTID_DATAHANDLING_SAVEDIFFCALTEST_H_
+#pragma once
 
 #include <Poco/File.h>
 #include <cxxtest/TestSuite.h>
@@ -200,5 +199,3 @@ public:
       Poco::File(filename).remove();
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEDIFFCALTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveDspacemapTest.h b/Framework/DataHandling/test/SaveDspacemapTest.h
index 0882e71ac79..c0e1c660a89 100644
--- a/Framework/DataHandling/test/SaveDspacemapTest.h
+++ b/Framework/DataHandling/test/SaveDspacemapTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEDSPACEMAPTEST_H_
-#define MANTID_DATAHANDLING_SAVEDSPACEMAPTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidDataHandling/LoadDspacemap.h"
@@ -117,5 +116,3 @@ public:
       Poco::File(filename).remove();
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEDSPACEMAPTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveFITSTest.h b/Framework/DataHandling/test/SaveFITSTest.h
index 7bfa59e8e31..652e7f51cd4 100644
--- a/Framework/DataHandling/test/SaveFITSTest.h
+++ b/Framework/DataHandling/test/SaveFITSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEFITSTEST_H_
-#define MANTID_DATAHANDLING_SAVEFITSTEST_H_
+#pragma once
 
 #include "MantidDataHandling/SaveFITS.h"
 
@@ -143,5 +142,3 @@ public:
         saved.remove());
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEFITSTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveFocusedXYETest.h b/Framework/DataHandling/test/SaveFocusedXYETest.h
index 713c9f4ac62..19e3783fdca 100644
--- a/Framework/DataHandling/test/SaveFocusedXYETest.h
+++ b/Framework/DataHandling/test/SaveFocusedXYETest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEFOCUSEDXYETEST_H_
-#define SAVEFOCUSEDXYETEST_H_
+#pragma once
 
 #include "MantidDataHandling/SaveFocusedXYE.h"
 
@@ -646,5 +645,3 @@ private:
     return saver;
   }
 };
-
-#endif // SAVEFOCUSEDXYETEST_H_
diff --git a/Framework/DataHandling/test/SaveFullprofResolutionTest.h b/Framework/DataHandling/test/SaveFullprofResolutionTest.h
index 86972222444..9bfadb39e28 100644
--- a/Framework/DataHandling/test/SaveFullprofResolutionTest.h
+++ b/Framework/DataHandling/test/SaveFullprofResolutionTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEFullprofRESOLUTIONTEST_H_
-#define MANTID_DATAHANDLING_SAVEFullprofRESOLUTIONTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -308,5 +307,3 @@ public:
     return;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEFullprofRESOLUTIONTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveGDATest.h b/Framework/DataHandling/test/SaveGDATest.h
index b3be210d72e..221578a3638 100644
--- a/Framework/DataHandling/test/SaveGDATest.h
+++ b/Framework/DataHandling/test/SaveGDATest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEGDATEST_H_
-#define MANTID_DATAHANDLING_SAVEGDATEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -314,5 +313,3 @@ const std::string SaveGDATest::PARAMS_FILE_TEXT =
     "INS  2PRCF 2   0.000000E+00   0.151242E+03   0.103200E+02   0.000000E+00\n"
     "INS  2PRCF 3   0.000000E+00   0.000000E+00   0.000000E+00\n"
     "0.000000E+00\n";
-
-#endif // MANTID_DATAHANDLING_SAVEGDATEST_H_
diff --git a/Framework/DataHandling/test/SaveGSASInstrumentFileTest.h b/Framework/DataHandling/test/SaveGSASInstrumentFileTest.h
index 9a2c58bbff3..a01cb51288a 100644
--- a/Framework/DataHandling/test/SaveGSASInstrumentFileTest.h
+++ b/Framework/DataHandling/test/SaveGSASInstrumentFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_ALGORITHMS_SAVEGSASINSTRUMENTFILETEST_H_
-#define MANTID_ALGORITHMS_SAVEGSASINSTRUMENTFILETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -531,5 +530,3 @@ public:
     return true;
   }
 };
-
-#endif /* MANTID_ALGORITHMS_SAVEGSASINSTRUMENTFILETEST_H_ */
diff --git a/Framework/DataHandling/test/SaveGSSTest.h b/Framework/DataHandling/test/SaveGSSTest.h
index 33d0127fe12..e22ea6823ba 100644
--- a/Framework/DataHandling/test/SaveGSSTest.h
+++ b/Framework/DataHandling/test/SaveGSSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEGSSTEST_H_
-#define SAVEGSSTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/Axis.h"
@@ -367,5 +366,3 @@ private:
 
   SaveGSS *m_alg = nullptr;
 };
-
-#endif // SAVEGSSTEST_H_
diff --git a/Framework/DataHandling/test/SaveILLCosmosAsciiTest.h b/Framework/DataHandling/test/SaveILLCosmosAsciiTest.h
index 71418abceb7..84e267de227 100644
--- a/Framework/DataHandling/test/SaveILLCosmosAsciiTest.h
+++ b/Framework/DataHandling/test/SaveILLCosmosAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEILLCOSMOSASCIITEST_H_
-#define MANTID_DATAHANDLING_SAVEILLCOSMOSASCIITEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -307,5 +306,4 @@ private:
   int m_points{2};
   std::vector<double> m_data;
   std::vector<double> m_zeros;
-};
-#endif /*MANTID_DATAHANDLING_SAVEILLCOSMOSASCIITEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SaveIsawDetCalTest.h b/Framework/DataHandling/test/SaveIsawDetCalTest.h
index 595267c8288..2221f2f618f 100644
--- a/Framework/DataHandling/test/SaveIsawDetCalTest.h
+++ b/Framework/DataHandling/test/SaveIsawDetCalTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEISAWDETCALTEST_H_
-#define MANTID_DATAHANDLING_SAVEISAWDETCALTEST_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace.h"
 #include "MantidDataHandling/SaveIsawDetCal.h"
@@ -54,5 +53,3 @@ public:
       Poco::File(filename).remove();
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEISAWDETCALTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveMaskTest.h b/Framework/DataHandling/test/SaveMaskTest.h
index ac94fa2e0bb..e1584c0c7cf 100644
--- a/Framework/DataHandling/test/SaveMaskTest.h
+++ b/Framework/DataHandling/test/SaveMaskTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEMASKINGTOFILETEST_H_
-#define MANTID_DATAHANDLING_SAVEMASKINGTOFILETEST_H_
+#pragma once
 
 #include "MantidDataHandling/SaveMask.h"
 
@@ -99,5 +98,3 @@ public:
     cleanfile.remove(false);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEMASKINGTOFILETEST_H_ */
diff --git a/Framework/DataHandling/test/SaveNISTDATTest.h b/Framework/DataHandling/test/SaveNISTDATTest.h
index 44400c291ff..2e8fda3652c 100644
--- a/Framework/DataHandling/test/SaveNISTDATTest.h
+++ b/Framework/DataHandling/test/SaveNISTDATTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVENISTDATTEST_H_
-#define SAVENISTDATTEST_H_
+#pragma once
 
 #include "MantidDataHandling/Load.h"
 #include "MantidDataHandling/SaveNISTDAT.h"
@@ -54,5 +53,3 @@ public:
     Poco::File(outputFile).remove();
   }
 };
-
-#endif /*SAVENISTDATTEST_H_*/
diff --git a/Framework/DataHandling/test/SaveNXSPETest.h b/Framework/DataHandling/test/SaveNXSPETest.h
index e9691bdfbd7..71525257205 100644
--- a/Framework/DataHandling/test/SaveNXSPETest.h
+++ b/Framework/DataHandling/test/SaveNXSPETest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVENXSPETEST_H_
-#define SAVENXSPETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -229,5 +228,3 @@ private:
     return boost::make_tuple(dims, signal, error);
   }
 };
-
-#endif /*SAVENXSPETEST_H_*/
diff --git a/Framework/DataHandling/test/SaveNXTomoTest.h b/Framework/DataHandling/test/SaveNXTomoTest.h
index 471f7bb2908..82a7768c5a6 100644
--- a/Framework/DataHandling/test/SaveNXTomoTest.h
+++ b/Framework/DataHandling/test/SaveNXTomoTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVENXTOMOTEST_H_
-#define SAVENXTOMOTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -418,5 +417,3 @@ private:
   std::string m_inputWS;
   int m_axisSize;
 };
-
-#endif /*SAVENXTOMOTEST_H_*/
diff --git a/Framework/DataHandling/test/SaveNXcanSASTest.h b/Framework/DataHandling/test/SaveNXcanSASTest.h
index 849c03ad294..6607bbdffff 100644
--- a/Framework/DataHandling/test/SaveNXcanSASTest.h
+++ b/Framework/DataHandling/test/SaveNXcanSASTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENXCANSASTEST_H_
-#define MANTID_DATAHANDLING_SAVENXCANSASTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -1005,5 +1004,3 @@ private:
     file.close();
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVENXCANSASTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveNexusESSTest.h b/Framework/DataHandling/test/SaveNexusESSTest.h
index 94771441e27..99b1845310e 100644
--- a/Framework/DataHandling/test/SaveNexusESSTest.h
+++ b/Framework/DataHandling/test/SaveNexusESSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENEXUSESSTEST_H_
-#define MANTID_DATAHANDLING_SAVENEXUSESSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -262,5 +261,3 @@ public:
     auto ws_out = test_utility::reload(handle.fullPath());
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVENEXUSESSTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveNexusGeometryTest.h b/Framework/DataHandling/test/SaveNexusGeometryTest.h
index 8c200e4f0c9..436664f8d3b 100644
--- a/Framework/DataHandling/test/SaveNexusGeometryTest.h
+++ b/Framework/DataHandling/test/SaveNexusGeometryTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVENEXUSGEOMETRYTEST_H_
-#define MANTID_DATAHANDLING_SAVENEXUSGEOMETRYTEST_H_
+#pragma once
 
 #include "MantidAPI/IEventWorkspace.h"
 #include "MantidAPI/ITableWorkspace.h"
@@ -215,5 +214,3 @@ public:
     TS_ASSERT(!saver.isExecuted());
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVENEXUSGEOMETRYTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveNexusProcessedTest.h b/Framework/DataHandling/test/SaveNexusProcessedTest.h
index 903e54a0629..b3bf80278c4 100644
--- a/Framework/DataHandling/test/SaveNexusProcessedTest.h
+++ b/Framework/DataHandling/test/SaveNexusProcessedTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVENEXUSPROCESSEDTEST_H_
-#define SAVENEXUSPROCESSEDTEST_H_
+#pragma once
 
 // These includes seem to make the difference between initialization of the
 // workspace names (workspace2D/1D etc), instrument classes and not for this
@@ -1086,5 +1085,4 @@ private:
   std::string inputFile;
   std::string outputSpace;
   bool clearfiles;
-};
-#endif /*SAVENEXUSPROCESSEDTEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SaveNexusTest.h b/Framework/DataHandling/test/SaveNexusTest.h
index 833d1e5749a..724b6ef0eea 100644
--- a/Framework/DataHandling/test/SaveNexusTest.h
+++ b/Framework/DataHandling/test/SaveNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVENEXUSTEST_H_
-#define SAVENEXUSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -114,5 +113,4 @@ private:
   SaveNexus algToBeTested;
   std::string outputFile;
   std::string title;
-};
-#endif /*SAVENEXUSTEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SaveOpenGenieAsciiTest.h b/Framework/DataHandling/test/SaveOpenGenieAsciiTest.h
index 217b3f919d2..518f60d7bce 100644
--- a/Framework/DataHandling/test/SaveOpenGenieAsciiTest.h
+++ b/Framework/DataHandling/test/SaveOpenGenieAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEOPENGENIEASCIITEST_H_
-#define SAVEOPENGENIEASCIITEST_H_
+#pragma once
 #include "MantidDataHandling/SaveOpenGenieAscii.h"
 
 #include "MantidDataHandling/Load.h"
@@ -94,5 +93,3 @@ private:
     return alg;
   }
 };
-
-#endif /* SAVEOPENGENIEASCIITEST_H_ */
diff --git a/Framework/DataHandling/test/SavePARTest.h b/Framework/DataHandling/test/SavePARTest.h
index 49cfb85448a..53aecc977af 100644
--- a/Framework/DataHandling/test/SavePARTest.h
+++ b/Framework/DataHandling/test/SavePARTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEPARTEST_H_
-#define SAVEPARTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -176,5 +175,3 @@ private:
     return inputWS;
   }
 };
-
-#endif /*SAVEPARTEST_H_*/
diff --git a/Framework/DataHandling/test/SavePDFGuiTest.h b/Framework/DataHandling/test/SavePDFGuiTest.h
index 4bdfe538813..d2a2d0245d8 100644
--- a/Framework/DataHandling/test/SavePDFGuiTest.h
+++ b/Framework/DataHandling/test/SavePDFGuiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEPDFGUITEST_H_
-#define MANTID_DATAHANDLING_SAVEPDFGUITEST_H_
+#pragma once
 
 #include <Poco/File.h>
 #include <cxxtest/TestSuite.h>
@@ -129,5 +128,3 @@ public:
     AnalysisDataService::Instance().deepRemoveGroup(groupName);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVEPDFGUITEST_H_ */
diff --git a/Framework/DataHandling/test/SavePHXTest.h b/Framework/DataHandling/test/SavePHXTest.h
index 09bc1f29161..4f1aa9d45fb 100644
--- a/Framework/DataHandling/test/SavePHXTest.h
+++ b/Framework/DataHandling/test/SavePHXTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEPHXTEST_H_
-#define SAVEPHXTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <fstream>
@@ -206,5 +205,3 @@ private:
     return inputWS;
   }
 };
-
-#endif /*SAVEPHXTEST_H_*/
diff --git a/Framework/DataHandling/test/SaveParameterFileTest.h b/Framework/DataHandling/test/SaveParameterFileTest.h
index ec70ec0e1f9..ceef868a513 100644
--- a/Framework/DataHandling/test/SaveParameterFileTest.h
+++ b/Framework/DataHandling/test/SaveParameterFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEPARAMETERFILETEST_H_
-#define SAVEPARAMETERFILETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -195,5 +194,3 @@ public:
 private:
   MatrixWorkspace_sptr m_ws;
 };
-
-#endif /*SAVEPARAMETERFILETEST_H_*/
diff --git a/Framework/DataHandling/test/SaveRKHTest.h b/Framework/DataHandling/test/SaveRKHTest.h
index 028860043a7..3eff74e3cde 100644
--- a/Framework/DataHandling/test/SaveRKHTest.h
+++ b/Framework/DataHandling/test/SaveRKHTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVERKHTEST_H_
-#define SAVERKHTEST_H_
+#pragma once
 
 #include "MantidAPI/WorkspaceFactory.h"
 #include "MantidDataHandling/SaveRKH.h"
@@ -279,5 +278,3 @@ private:
     return ws;
   }
 };
-
-#endif // SAVERKHTEST_H_
diff --git a/Framework/DataHandling/test/SaveRMCProfileTest.h b/Framework/DataHandling/test/SaveRMCProfileTest.h
index ed3643e8760..78630f05465 100644
--- a/Framework/DataHandling/test/SaveRMCProfileTest.h
+++ b/Framework/DataHandling/test/SaveRMCProfileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVERMCPROFILETEST_H_
-#define MANTID_DATAHANDLING_SAVERMCPROFILETEST_H_
+#pragma once
 
 #include <Poco/File.h>
 #include <cxxtest/TestSuite.h>
@@ -136,5 +135,3 @@ public:
     AnalysisDataService::Instance().deepRemoveGroup(groupName);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SAVERMCPROFILETEST_H_ */
diff --git a/Framework/DataHandling/test/SaveReflCustomAsciiTest.h b/Framework/DataHandling/test/SaveReflCustomAsciiTest.h
index 06cbb34c3c7..5b66a08765e 100644
--- a/Framework/DataHandling/test/SaveReflCustomAsciiTest.h
+++ b/Framework/DataHandling/test/SaveReflCustomAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEREFLCUSTOMASCIITEST_H_
-#define SAVEREFLCUSTOMASCIITEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -254,5 +253,4 @@ private:
   }
   std::string m_filename, m_name, m_long_filename;
   std::vector<double> m_dataX, m_dataY, m_dataE;
-};
-#endif /*SAVEREFLCUSTOMASCIITEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SaveReflThreeColumnAsciiTest.h b/Framework/DataHandling/test/SaveReflThreeColumnAsciiTest.h
index 65f84327359..28660e35b80 100644
--- a/Framework/DataHandling/test/SaveReflThreeColumnAsciiTest.h
+++ b/Framework/DataHandling/test/SaveReflThreeColumnAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVEREFLTHREECOLUMNASCIITEST_H_
-#define SAVEREFLTHREECOLUMNASCIITEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -236,5 +235,3 @@ private:
   std::string m_filename, m_name, m_long_filename;
   std::vector<double> m_dataX, m_dataY, m_dataE;
 };
-
-#endif /*SAVEREFLTHREECOLUMNASCIITEST_H_*/
diff --git a/Framework/DataHandling/test/SaveReflectometryAsciiTest.h b/Framework/DataHandling/test/SaveReflectometryAsciiTest.h
index d0693246f20..7d25e466620 100644
--- a/Framework/DataHandling/test/SaveReflectometryAsciiTest.h
+++ b/Framework/DataHandling/test/SaveReflectometryAsciiTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVEReflectometryAsciiTEST_H_
-#define MANTID_DATAHANDLING_SAVEReflectometryAsciiTEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -778,5 +777,4 @@ private:
   bool not_empty(std::ifstream &in) {
     return in.peek() != std::ifstream::traits_type::eof();
   }
-};
-#endif /*MANTID_DATAHANDLING_SAVEReflectometryAsciiTEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SaveSESANSTest.h b/Framework/DataHandling/test/SaveSESANSTest.h
index f34feb0e4b1..5b8fe5282f1 100644
--- a/Framework/DataHandling/test/SaveSESANSTest.h
+++ b/Framework/DataHandling/test/SaveSESANSTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SAVESESANSTEST_H_
-#define MANTID_DATAHANDLING_SAVESESANSTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -136,5 +135,3 @@ private:
   const double ln2 = log(2.0);
   const double echoConstant = 1.5;
 };
-
-#endif /* MANTID_DATAHANDLING_SAVESESANSTEST_H_ */
diff --git a/Framework/DataHandling/test/SaveSPETest.h b/Framework/DataHandling/test/SaveSPETest.h
index 9c840ceb1f0..a47fca9b566 100644
--- a/Framework/DataHandling/test/SaveSPETest.h
+++ b/Framework/DataHandling/test/SaveSPETest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVESPETEST_H_
-#define SAVESPETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -206,5 +205,3 @@ private:
 private:
   IAlgorithm *saver;
 };
-
-#endif /*SAVESPETEST_H_*/
diff --git a/Framework/DataHandling/test/SaveStlTest.h b/Framework/DataHandling/test/SaveStlTest.h
index bf44d53a94e..9a02116c049 100644
--- a/Framework/DataHandling/test/SaveStlTest.h
+++ b/Framework/DataHandling/test/SaveStlTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVE_STL_TEST_H_
-#define SAVE_STL_TEST_H_
+#pragma once
 #include "MantidAPI/FileFinder.h"
 #include "MantidDataHandling//SaveStl.h"
 #include "MantidDataHandling/LoadBinaryStl.h"
@@ -88,5 +87,4 @@ public:
   const std::string cubePath =
       FileFinder::Instance().getFullPath("cubeBin.stl");
   std::string path;
-};
-#endif /*SAVE_STL_TEST_H_*/
\ No newline at end of file
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SaveTBLTest.h b/Framework/DataHandling/test/SaveTBLTest.h
index d2dc444cd4c..1c144f0a57d 100644
--- a/Framework/DataHandling/test/SaveTBLTest.h
+++ b/Framework/DataHandling/test/SaveTBLTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVETBLTEST_H_
-#define SAVETBLTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -451,5 +450,4 @@ private:
   std::string m_name;
   std::string m_filename;
   std::string m_abspath;
-};
-#endif /*SAVETBLTEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SaveToSNSHistogramNexusTest.h b/Framework/DataHandling/test/SaveToSNSHistogramNexusTest.h
index 13f7d3f663e..d7772ce2e7f 100644
--- a/Framework/DataHandling/test/SaveToSNSHistogramNexusTest.h
+++ b/Framework/DataHandling/test/SaveToSNSHistogramNexusTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SAVESNSNEXUSTEST_H_
-#define SAVESNSNEXUSTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmFactory.h"
 #include "MantidAPI/IAlgorithm.h"
@@ -58,5 +57,4 @@ private:
   SaveToSNSHistogramNexus algToBeTested;
   std::string outputFile;
   std::string title;
-};
-#endif /*SaveToSNSHistogramNexusTEST_H_*/
+};
\ No newline at end of file
diff --git a/Framework/DataHandling/test/SetBeamTest.h b/Framework/DataHandling/test/SetBeamTest.h
index d2a8534da5b..d8bf13d9939 100644
--- a/Framework/DataHandling/test/SetBeamTest.h
+++ b/Framework/DataHandling/test/SetBeamTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SETBEAMTEST_H_
-#define MANTID_DATAHANDLING_SETBEAMTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -121,5 +120,3 @@ private:
     return props;
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SETBEAMTEST_H_ */
diff --git a/Framework/DataHandling/test/SetSampleMaterialTest.h b/Framework/DataHandling/test/SetSampleMaterialTest.h
index 6adb0380a53..fe1273aa1f7 100644
--- a/Framework/DataHandling/test/SetSampleMaterialTest.h
+++ b/Framework/DataHandling/test/SetSampleMaterialTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SetSampleMaterialTEST_H_
-#define SetSampleMaterialTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -284,5 +283,3 @@ public:
     TS_ASSERT_DELTA(material.numberDensity(), 0.23 * (2. + 3.), 1e-12)
   }
 };
-
-#endif /*SetSampleMaterialTEST_H_*/
diff --git a/Framework/DataHandling/test/SetSampleTest.h b/Framework/DataHandling/test/SetSampleTest.h
index 8a8544c605e..875d08b4749 100644
--- a/Framework/DataHandling/test/SetSampleTest.h
+++ b/Framework/DataHandling/test/SetSampleTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SETSAMPLETEST_H_
-#define MANTID_DATAHANDLING_SETSAMPLETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -767,5 +766,3 @@ private:
   const std::string m_instName = "ISIS_Histogram";
   const std::string m_envName = "TestEnv";
 };
-
-#endif /* MANTID_ALGORITHMS_SETSAMPLETEST_H_ */
diff --git a/Framework/DataHandling/test/SetScalingPSDTest.h b/Framework/DataHandling/test/SetScalingPSDTest.h
index d31702a90e4..3813cb5add2 100644
--- a/Framework/DataHandling/test/SetScalingPSDTest.h
+++ b/Framework/DataHandling/test/SetScalingPSDTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SETSCALINGPSDTEST_H_
-#define SETSCALINGPSDTEST_H_
+#pragma once
 
 #include "MantidAPI/SpectrumInfo.h"
 #include "MantidDataHandling/LoadEmptyInstrument.h"
@@ -180,5 +179,3 @@ private:
   /// Constant shift
   const double m_y_offset;
 };
-
-#endif /*SETSCALINGPSDTEST_H_*/
diff --git a/Framework/DataHandling/test/SortTableWorkspaceTest.h b/Framework/DataHandling/test/SortTableWorkspaceTest.h
index 112e4d15de0..8c8b773cfab 100644
--- a/Framework/DataHandling/test/SortTableWorkspaceTest.h
+++ b/Framework/DataHandling/test/SortTableWorkspaceTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_SORTTABLEWORKSPACETEST_H_
-#define MANTID_DATAHANDLING_SORTTABLEWORKSPACETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -590,5 +589,3 @@ public:
     TS_ASSERT(!alg.isExecuted());
   }
 };
-
-#endif /* MANTID_DATAHANDLING_SORTTABLEWORKSPACETEST_H_ */
diff --git a/Framework/DataHandling/test/StartAndEndTimeFromNexusFileExtractorTest.h b/Framework/DataHandling/test/StartAndEndTimeFromNexusFileExtractorTest.h
index 20195f8a73a..ea9247a2dbf 100644
--- a/Framework/DataHandling/test/StartAndEndTimeFromNexusFileExtractorTest.h
+++ b/Framework/DataHandling/test/StartAndEndTimeFromNexusFileExtractorTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_DATAHANDLING_STARTANDENDTIMEFROMNEXUSFILEEXTRACTORTEST_H_
-#define MANTID_DATAHANDLING_STARTANDENDTIMEFROMNEXUSFILEEXTRACTORTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -89,5 +88,3 @@ private:
                endTimeExtracted == expectedEndTimeString);
   }
 };
-
-#endif /* MANTID_DATAHANDLING_STARTANDENDTIMEFROMNEXUSFILEEXTRACTORTEST_H_ */
diff --git a/Framework/DataHandling/test/UpdateInstrumentFromFileTest.h b/Framework/DataHandling/test/UpdateInstrumentFromFileTest.h
index f8b3191eafd..0ed7df3c1e8 100644
--- a/Framework/DataHandling/test/UpdateInstrumentFromFileTest.h
+++ b/Framework/DataHandling/test/UpdateInstrumentFromFileTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef UPDATEINSTRUMENTTESTFROMFILE_H_
-#define UPDATEINSTRUMENTTESTFROMFILE_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -311,5 +310,3 @@ private:
   std::string wsName;
   std::string xmlFile;
 };
-
-#endif /*UPDATEINSTRUMENTTESTFROMFILE_H_*/
diff --git a/Framework/DataHandling/test/XMLInstrumentParameterTest.h b/Framework/DataHandling/test/XMLInstrumentParameterTest.h
index 5689c599059..f17e095d5b2 100644
--- a/Framework/DataHandling/test/XMLInstrumentParameterTest.h
+++ b/Framework/DataHandling/test/XMLInstrumentParameterTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef XMLLOGFILETEST_H_
-#define XMLLOGFILETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -109,5 +108,3 @@ public:
     TS_ASSERT_DELTA(testParamEntry.createParamValue(dummy), 0.0, 0.0001);
   }
 };
-
-#endif /*XMLLOGFILETEST_H_*/
-- 
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