diff --git a/Framework/LiveData/inc/MantidLiveData/ADARA/ADARA.h b/Framework/LiveData/inc/MantidLiveData/ADARA/ADARA.h
index a8bec6329f91b97c1c417c829290dc5bb4213108..9e7ffa447ea5a089697b98b8a1e7e3a843da25cc 100644
--- a/Framework/LiveData/inc/MantidLiveData/ADARA/ADARA.h
+++ b/Framework/LiveData/inc/MantidLiveData/ADARA/ADARA.h
@@ -1,5 +1,4 @@
-#ifndef __ADARA_H
-#define __ADARA_H
+#pragma once
 
 //
 // SNS ADARA SYSTEM - Common Library
@@ -205,5 +204,3 @@ public:
 enum { EPICS_EPOCH_OFFSET = 631152000 };
 
 } /* namespace ADARA */
-
-#endif /* __ADARA_H */
diff --git a/Framework/LiveData/inc/MantidLiveData/ADARA/ADARAPackets.h b/Framework/LiveData/inc/MantidLiveData/ADARA/ADARAPackets.h
index 7b118d6c300e8faedcc3201d22ed081d546305d5..fbe9f0cd19a38b446049d8c21f0cf37ee036f867 100644
--- a/Framework/LiveData/inc/MantidLiveData/ADARA/ADARAPackets.h
+++ b/Framework/LiveData/inc/MantidLiveData/ADARA/ADARAPackets.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef __ADARA_PACKETS_H
-#define __ADARA_PACKETS_H
+#pragma once
 
 #include <cstdint>
 #include <cstring>
@@ -752,5 +751,3 @@ private:
 };
 
 } // namespace ADARA
-
-#endif /* __ADARA_PACKETS_H */
diff --git a/Framework/LiveData/inc/MantidLiveData/ADARA/ADARAParser.h b/Framework/LiveData/inc/MantidLiveData/ADARA/ADARAParser.h
index f25b91e9d14f6bcfb5e20f323164fe2fa5e4494f..b1a2b2d3dc372aa5441090442fc2a2e4f8c1da6d 100644
--- a/Framework/LiveData/inc/MantidLiveData/ADARA/ADARAParser.h
+++ b/Framework/LiveData/inc/MantidLiveData/ADARA/ADARAParser.h
@@ -1,5 +1,4 @@
-#ifndef __ADARA_PARSER_H
-#define __ADARA_PARSER_H
+#pragma once
 
 #include <cstdint>
 #include <map>
@@ -196,5 +195,3 @@ private:
 };
 
 } // namespace ADARA
-
-#endif /* __ADARA_PARSER_H */
diff --git a/Framework/LiveData/inc/MantidLiveData/Exception.h b/Framework/LiveData/inc/MantidLiveData/Exception.h
index 6194ad0516145ba266a0e5c33eacab8d235e3342..6201c01339b302c8eb4053e06b6741868cfdd043 100644
--- a/Framework/LiveData/inc/MantidLiveData/Exception.h
+++ b/Framework/LiveData/inc/MantidLiveData/Exception.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_EXCEPTION_H_
-#define MANTID_LIVEDATA_EXCEPTION_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -34,5 +33,3 @@ public:
 } // namespace Exception
 } // namespace LiveData
 } // namespace Mantid
-
-#endif // MANTID_LIVEDATA_EXCEPTION_H_
diff --git a/Framework/LiveData/inc/MantidLiveData/FakeEventDataListener.h b/Framework/LiveData/inc/MantidLiveData/FakeEventDataListener.h
index 608aeefa423a693ce1c7a0c7bc35053c4af8b0b3..25580388434f9fb9439ef3615be15947392c5bd9 100644
--- a/Framework/LiveData/inc/MantidLiveData/FakeEventDataListener.h
+++ b/Framework/LiveData/inc/MantidLiveData/FakeEventDataListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_FAKEEVENTDATALISTENER_H_
-#define MANTID_LIVEDATA_FAKEEVENTDATALISTENER_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -71,5 +70,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_FAKEEVENTDATALISTENER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/FileEventDataListener.h b/Framework/LiveData/inc/MantidLiveData/FileEventDataListener.h
index fbc2d60623fb758ddd22f2b60ed5aadeabfeb43a..1b4610cff7e193f87844d08f25813b0c71bdd296 100644
--- a/Framework/LiveData/inc/MantidLiveData/FileEventDataListener.h
+++ b/Framework/LiveData/inc/MantidLiveData/FileEventDataListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_FILEEVENTDATALISTENER_H_
-#define MANTID_LIVEDATA_FILEEVENTDATALISTENER_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -70,5 +69,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_FILEEVENTDATALISTENER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/ISIS/FakeISISEventDAE.h b/Framework/LiveData/inc/MantidLiveData/ISIS/FakeISISEventDAE.h
index c2ab438c1f1234f3032eadf6839cd861a8180f2a..f69ecf450dbaf8c7e6b99a791f618c051f55b19b 100644
--- a/Framework/LiveData/inc/MantidLiveData/ISIS/FakeISISEventDAE.h
+++ b/Framework/LiveData/inc/MantidLiveData/ISIS/FakeISISEventDAE.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_FAKEISISEVENTDAE_H_
-#define MANTID_LIVEDATA_FAKEISISEVENTDAE_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -44,5 +43,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /*MANTID_LIVEDATA_FAKEEventSHISTODAE_H_*/
diff --git a/Framework/LiveData/inc/MantidLiveData/ISIS/FakeISISHistoDAE.h b/Framework/LiveData/inc/MantidLiveData/ISIS/FakeISISHistoDAE.h
index 7e69bb3786668907cbf88edfdcf5889a8436fa9d..1c82f0d4a6534de44faec573a1df98f4ff796e9c 100644
--- a/Framework/LiveData/inc/MantidLiveData/ISIS/FakeISISHistoDAE.h
+++ b/Framework/LiveData/inc/MantidLiveData/ISIS/FakeISISHistoDAE.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_FAKEISISHISTODAE_H_
-#define MANTID_LIVEDATA_FAKEISISHISTODAE_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -51,5 +50,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /*MANTID_LIVEDATA_FAKEISISHISTODAE_H_*/
diff --git a/Framework/LiveData/inc/MantidLiveData/ISIS/ISISHistoDataListener.h b/Framework/LiveData/inc/MantidLiveData/ISIS/ISISHistoDataListener.h
index 2d74f087bf3cf21f4a435f92ecb668afd9263c85..f4166f1ad9248ad23801df6823f4c40fb8190d5f 100644
--- a/Framework/LiveData/inc/MantidLiveData/ISIS/ISISHistoDataListener.h
+++ b/Framework/LiveData/inc/MantidLiveData/ISIS/ISISHistoDataListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_ISISHISTODATALISTENER_H_
-#define MANTID_LIVEDATA_ISISHISTODATALISTENER_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -127,5 +126,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_ISISHISTODATALISTENER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/ISIS/ISISLiveEventDataListener.h b/Framework/LiveData/inc/MantidLiveData/ISIS/ISISLiveEventDataListener.h
index 9c16f05a281ee8a95338a9121d6fd2d5fd46c8bf..d632e08f2e37e7f614a8c4c07080f4a485e337ee 100644
--- a/Framework/LiveData/inc/MantidLiveData/ISIS/ISISLiveEventDataListener.h
+++ b/Framework/LiveData/inc/MantidLiveData/ISIS/ISISLiveEventDataListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_ISISLIVEEVENTDATALISTENER_H_
-#define MANTID_LIVEDATA_ISISLIVEEVENTDATALISTENER_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -218,5 +217,3 @@ protected:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /*MANTID_LIVEDATA_ISISLIVEEVENTDATALISTENER_H_*/
diff --git a/Framework/LiveData/inc/MantidLiveData/ISIS/TCPEventStreamDefs.h b/Framework/LiveData/inc/MantidLiveData/ISIS/TCPEventStreamDefs.h
index a958d4420845a079cc15c67b37b7e6bdb0716a6a..ec3e2c6a63c7707d2eccda869cfefeb094687070 100644
--- a/Framework/LiveData/inc/MantidLiveData/ISIS/TCPEventStreamDefs.h
+++ b/Framework/LiveData/inc/MantidLiveData/ISIS/TCPEventStreamDefs.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef TCP_EVENT_STREAM_DEFS_H
-#define TCP_EVENT_STREAM_DEFS_H
+#pragma once
 
 #include "MantidKernel/WarningSuppressions.h"
 
@@ -195,5 +194,4 @@ struct TCPStreamEventDataSE {
 } // namespace LiveData
 } // namespace Mantid
 
-GNU_DIAG_ON("type-limits")
-#endif /* TCP_EVENT_STREAM_DEFS_H */
+GNU_DIAG_ON("type-limits")
\ No newline at end of file
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaBroker.h b/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaBroker.h
index 56d30af59670f4b26a623a912f3c3243095f30b4..5224cd0526f330946703bdd4e038d9ec22dd707b 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaBroker.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaBroker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_IKAFKABROKER_H_
-#define MANTID_LIVEDATA_IKAFKABROKER_H_
+#pragma once
 
 #include "MantidLiveData/Kafka/IKafkaStreamSubscriber.h"
 #include <memory>
@@ -32,5 +31,3 @@ public:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_IKAFKABROKER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaStreamDecoder.h b/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaStreamDecoder.h
index 722981f8d7c9a73fffb6f46bc302689cb2714916..53526b8efe93954487e6d31690305b2075dc12e5 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaStreamDecoder.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaStreamDecoder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_IKAFKASTREAMDECODER_H_
-#define MANTID_LIVEDATA_IKAFKASTREAMDECODER_H_
+#pragma once
 
 #include "MantidAPI/SpectraDetectorTypes.h"
 #include "MantidDataObjects/EventWorkspace.h"
@@ -242,5 +241,4 @@ protected:
   std::string getDetSpecMapForRun(const RunStartStruct &runStartStruct);
 };
 } // namespace LiveData
-} // namespace Mantid
-#endif // MANTID_LIVEDATA_IKAFKASTREAMDECODER_H_
+} // namespace Mantid
\ No newline at end of file
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaStreamSubscriber.h b/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaStreamSubscriber.h
index 9543b15db0821b52b7872423b5a0145aa6404db2..65cae78fb72498317cd697e5701428e6a1aecf91 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaStreamSubscriber.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/IKafkaStreamSubscriber.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_IKAFKASTREAMSUBSCRIBER_H_
-#define MANTID_LIVEDATA_IKAFKASTREAMSUBSCRIBER_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include <string>
@@ -45,5 +44,3 @@ public:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_IKAFKASTREAMSUBSCRIBER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaBroker.h b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaBroker.h
index 12fb4b74e1bb4f87a841a1ff501850aecf186f01..37af94fa1fdaf7050554e6c60f68f20fdb1a8227 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaBroker.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaBroker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_KAFKABROKER_H_
-#define MANTID_LIVEDATA_KAFKABROKER_H_
+#pragma once
 
 #include "MantidLiveData/Kafka/IKafkaBroker.h"
 
@@ -32,5 +31,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_KAFKABROKER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaEventListener.h b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaEventListener.h
index 59f4a3b506006589b81c0fd898f4b267b5d8492b..773d3f550765df7a15b6a78e0952066cf6b83e91 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaEventListener.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaEventListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_KAFKAEVENTLISTENER_H_
-#define MANTID_LIVEDATA_KAFKAEVENTLISTENER_H_
+#pragma once
 //----------------------------------------------------------------------
 // Includes
 //----------------------------------------------------------------------
@@ -71,5 +70,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /*MANTID_LIVEDATA_KAFKAEVENTLISTENER_H_*/
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaEventStreamDecoder.h b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaEventStreamDecoder.h
index dad15c81599fb148b4c799614098ceb225964c7a..bc9166bb94a04f15c762c7e5889069ca592faca8 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaEventStreamDecoder.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaEventStreamDecoder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_KAFKAEVENTSTREAMDECODER_H_
-#define MANTID_LIVEDATA_KAFKAEVENTSTREAMDECODER_H_
+#pragma once
 
 #include "MantidAPI/SpectraDetectorTypes.h"
 #include "MantidDataObjects/EventWorkspace.h"
@@ -90,5 +89,3 @@ DLLExport std::vector<size_t> computeGroupBoundaries(
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_KAFKAEVENTSTREAMDECODER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaHistoListener.h b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaHistoListener.h
index b87aa1735433ac58fd46288c5af9f602f6e70270..f7c6b0f0c1538d707b503e63f066f173f757715a 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaHistoListener.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaHistoListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_ISISKAFKAHISTOLISTENER_H_
-#define MANTID_LIVEDATA_ISISKAFKAHISTOLISTENER_H_
+#pragma once
 //----------------------------------------------------------------------
 // Includes
 //----------------------------------------------------------------------
@@ -63,5 +62,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /*MANTID_LIVEDATA_ISISKAFKAHISTOLISTENER_H_*/
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaHistoStreamDecoder.h b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaHistoStreamDecoder.h
index 2608a036f6e0c6815976cc73ffd0214b4809bb12..b21c992a04202dbf74d2504451eb3fb6a81361f9 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaHistoStreamDecoder.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaHistoStreamDecoder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_ISISKAFKAHISTOSTREAMDECODER_H_
-#define MANTID_LIVEDATA_ISISKAFKAHISTOSTREAMDECODER_H_
+#pragma once
 
 #include "MantidDataObjects/Workspace2D.h"
 #include "MantidLiveData/Kafka/IKafkaBroker.h"
@@ -54,5 +53,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_ISISKAFKAHISTOSTREAMDECODER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaTopicSubscriber.h b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaTopicSubscriber.h
index 4d74fa43b5be0bac83a695ea5846ff62ed382f62..554d04fe95c45e319d9b7070d8bb84db5accd06c 100644
--- a/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaTopicSubscriber.h
+++ b/Framework/LiveData/inc/MantidLiveData/Kafka/KafkaTopicSubscriber.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_KAFKAEVENTSUBSCRIBER_H_
-#define MANTID_LIVEDATA_KAFKAEVENTSUBSCRIBER_H_
+#pragma once
 
 #include "MantidLiveData/Kafka/IKafkaStreamSubscriber.h"
 #include <librdkafka/rdkafkacpp.h>
@@ -73,5 +72,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_KAFKAEVENTSUBSCRIBER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/LiveDataAlgorithm.h b/Framework/LiveData/inc/MantidLiveData/LiveDataAlgorithm.h
index 0a83ec811889796e04f3a21eabf97ddff38e8529..bbc978fd02c027f4dec18167163f063d01844c17 100644
--- a/Framework/LiveData/inc/MantidLiveData/LiveDataAlgorithm.h
+++ b/Framework/LiveData/inc/MantidLiveData/LiveDataAlgorithm.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_LIVEDATAALGORITHM_H_
-#define MANTID_LIVEDATA_LIVEDATAALGORITHM_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/ILiveListener.h"
@@ -51,5 +50,3 @@ protected:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_LIVEDATAALGORITHM_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/LoadLiveData.h b/Framework/LiveData/inc/MantidLiveData/LoadLiveData.h
index 45b8ee4c7194dba7c733ec771aaaa5236107d56e..d4ef9927e3c53a6a2f95887b941630c984165b6d 100644
--- a/Framework/LiveData/inc/MantidLiveData/LoadLiveData.h
+++ b/Framework/LiveData/inc/MantidLiveData/LoadLiveData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_LOADLIVEDATA_H_
-#define MANTID_LIVEDATA_LOADLIVEDATA_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/Workspace_fwd.h"
@@ -62,5 +61,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_LOADLIVEDATA_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/MonitorLiveData.h b/Framework/LiveData/inc/MantidLiveData/MonitorLiveData.h
index 74697c2c27193049620e5eae40ac072a22147e68..c90bb568f97f5c5c074aa253c6d8dacc2ab211be 100644
--- a/Framework/LiveData/inc/MantidLiveData/MonitorLiveData.h
+++ b/Framework/LiveData/inc/MantidLiveData/MonitorLiveData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_MONITORLIVEDATA_H_
-#define MANTID_LIVEDATA_MONITORLIVEDATA_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidLiveData/DllConfig.h"
@@ -44,5 +43,3 @@ public:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_MONITORLIVEDATA_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/PrecompiledHeader.h b/Framework/LiveData/inc/MantidLiveData/PrecompiledHeader.h
index 29063241b264b9dea3606f104c097411392f15ef..7bbfdd105f077d6e7c3d3d828bb324574b819903 100644
--- a/Framework/LiveData/inc/MantidLiveData/PrecompiledHeader.h
+++ b/Framework/LiveData/inc/MantidLiveData/PrecompiledHeader.h
@@ -4,10 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_PRECOMPILEDHEADER_H_
-#define MANTID_LIVEDATA_PRECOMPILEDHEADER_H_
+#pragma once
 
 // Algorithm
 #include "MantidAPI/Algorithm.h"
-
-#endif // MANTID_LIVEDATA_PRECOMPILEDHEADER_H_
diff --git a/Framework/LiveData/inc/MantidLiveData/SNSLiveEventDataListener.h b/Framework/LiveData/inc/MantidLiveData/SNSLiveEventDataListener.h
index 71ba12e70bb39221e5df31dd2708e4b14e93a8e6..24d4dc44806c7961c4c0b423b68686ee22408bac 100644
--- a/Framework/LiveData/inc/MantidLiveData/SNSLiveEventDataListener.h
+++ b/Framework/LiveData/inc/MantidLiveData/SNSLiveEventDataListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_SNSLIVEEVENTDATALISTENER_H_
-#define MANTID_LIVEDATA_SNSLIVEEVENTDATALISTENER_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -213,5 +212,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_FAKEEVENTDATALISTENER_H_ */
diff --git a/Framework/LiveData/inc/MantidLiveData/StartLiveData.h b/Framework/LiveData/inc/MantidLiveData/StartLiveData.h
index 00a7664d0d492980eb0554aaf55731307bc82a85..2445616c116046800137b8c36d4bbe2d89beb34e 100644
--- a/Framework/LiveData/inc/MantidLiveData/StartLiveData.h
+++ b/Framework/LiveData/inc/MantidLiveData/StartLiveData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_STARTLIVEDATA_H_
-#define MANTID_LIVEDATA_STARTLIVEDATA_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidLiveData/DllConfig.h"
@@ -50,5 +49,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_STARTLIVEDATA_H_ */
diff --git a/Framework/LiveData/src/ISIS/DAE/idc.h b/Framework/LiveData/src/ISIS/DAE/idc.h
index c55552a1fde5ed1a6419e1903e076baf95dffcc2..5d3c15ac9fce10424df52db3cc8165e1dee8f4f0 100644
--- a/Framework/LiveData/src/ISIS/DAE/idc.h
+++ b/Framework/LiveData/src/ISIS/DAE/idc.h
@@ -1,5 +1,4 @@
-#ifndef IDC_H
-#define IDC_H
+#pragma once
 /**
 
     @file idc.h
@@ -118,5 +117,3 @@ int IDCreport(int status, int code, const char *format, ...);
 #ifdef __cplusplus
 }
 #endif
-
-#endif /* IDC_H */
diff --git a/Framework/LiveData/src/ISIS/DAE/isisds_command.h b/Framework/LiveData/src/ISIS/DAE/isisds_command.h
index 145e9493c9327dbd47b43097163c239485e9a096..ec93de920c1ca63cf77ae20d9f06d1e275796994 100644
--- a/Framework/LiveData/src/ISIS/DAE/isisds_command.h
+++ b/Framework/LiveData/src/ISIS/DAE/isisds_command.h
@@ -17,8 +17,7 @@
 
 ///@cond nodoc
 
-#ifndef ISISDS_COMMAND_H
-#define ISISDS_COMMAND_H
+#pragma once
 
 using isisds_error_report_t = void (*)(int, int, const char *);
 
@@ -71,5 +70,3 @@ int isisds_report(int status, int code, const char *format, ...);
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */
-
-#endif /* ISISDS_COMMAND_H */
diff --git a/Framework/LiveData/src/Kafka/private/Schema/ai34_det_counts_generated.h b/Framework/LiveData/src/Kafka/private/Schema/ai34_det_counts_generated.h
index a5113b2b2db0c39cc793833a8cee6a1518264df5..155bbc15a42424f98a9b868a522b48efefaa8ac9 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/ai34_det_counts_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/ai34_det_counts_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_AI34DETCOUNTS_H_
-#define FLATBUFFERS_GENERATED_AI34DETCOUNTS_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -137,5 +136,3 @@ inline void FinishSizePrefixedPulseImageBuffer(
     flatbuffers::Offset<PulseImage> root) {
   fbb.FinishSizePrefixed(root, PulseImageIdentifier());
 }
-
-#endif  // FLATBUFFERS_GENERATED_AI34DETCOUNTS_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/df12_det_spec_map_generated.h b/Framework/LiveData/src/Kafka/private/Schema/df12_det_spec_map_generated.h
index 653d64c75b382d787126d8f4a2d4371a2573ea48..0756ea4a7b351a52fa338d0d9e0968252f85c5e2 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/df12_det_spec_map_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/df12_det_spec_map_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_DF12DETSPECMAP_H_
-#define FLATBUFFERS_GENERATED_DF12DETSPECMAP_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -137,5 +136,3 @@ inline void FinishSizePrefixedSpectraDetectorMappingBuffer(
     flatbuffers::Offset<SpectraDetectorMapping> root) {
   fbb.FinishSizePrefixed(root, SpectraDetectorMappingIdentifier());
 }
-
-#endif  // FLATBUFFERS_GENERATED_DF12DETSPECMAP_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/dtdb_adc_pulse_debug_generated.h b/Framework/LiveData/src/Kafka/private/Schema/dtdb_adc_pulse_debug_generated.h
index 919ce08b6b36dbcc152e702975c3208ff697590f..ef160b9d01f8e420b9a4acf74d4b234dcfe3442b 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/dtdb_adc_pulse_debug_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/dtdb_adc_pulse_debug_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_DTDBADCPULSEDEBUG_H_
-#define FLATBUFFERS_GENERATED_DTDBADCPULSEDEBUG_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -127,5 +126,3 @@ inline flatbuffers::Offset<AdcPulseDebug> CreateAdcPulseDebugDirect(
       threshold_time ? _fbb.CreateVector<uint64_t>(*threshold_time) : 0,
       peak_time ? _fbb.CreateVector<uint64_t>(*peak_time) : 0);
 }
-
-#endif  // FLATBUFFERS_GENERATED_DTDBADCPULSEDEBUG_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/ev42_events_generated.h b/Framework/LiveData/src/Kafka/private/Schema/ev42_events_generated.h
index eb82e270f8ba493f23f0d67fda1cb35518f0f977..9f3d6b611c5b404c92d3e8c3be95587dd0198945 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/ev42_events_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/ev42_events_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_EV42EVENTS_H_
-#define FLATBUFFERS_GENERATED_EV42EVENTS_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -293,5 +292,3 @@ inline void FinishSizePrefixedEventMessageBuffer(
     flatbuffers::Offset<EventMessage> root) {
   fbb.FinishSizePrefixed(root, EventMessageIdentifier());
 }
-
-#endif  // FLATBUFFERS_GENERATED_EV42EVENTS_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/f142_logdata_generated.h b/Framework/LiveData/src/Kafka/private/Schema/f142_logdata_generated.h
index 70ab14ed2d80c0cbbf83460055fb14d364d0f913..e27a36d05d450cd4d6bc2183e57a5750de0f359e 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/f142_logdata_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/f142_logdata_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_F142LOGDATA_H_
-#define FLATBUFFERS_GENERATED_F142LOGDATA_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -1811,5 +1810,3 @@ inline void FinishSizePrefixedLogDataBuffer(
   fbb.FinishSizePrefixed(root, LogDataIdentifier());
 }
 }
-
-#endif  // FLATBUFFERS_GENERATED_F142LOGDATA_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/base.h b/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/base.h
index 3045bc9db947dd58ecd52b6a36f3ddad6e12f95c..3e194f3bca41a8a5f5c08df5e6c338705261f4ee 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/base.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/base.h
@@ -1,5 +1,4 @@
-#ifndef FLATBUFFERS_BASE_H_
-#define FLATBUFFERS_BASE_H_
+#pragma once
 
 // clang-format off
 #if defined(FLATBUFFERS_MEMORY_LEAK_TRACKING) && \
@@ -277,5 +276,4 @@ inline size_t PaddingBytes(size_t buf_size, size_t scalar_size) {
   return ((~buf_size) + 1) & (scalar_size - 1);
 }
 
-}  // namespace flatbuffers
-#endif  // FLATBUFFERS_BASE_H_
+}  // namespace flatbuffers
\ No newline at end of file
diff --git a/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/flatbuffers.h b/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/flatbuffers.h
index 36f71c57d775358b2f76453aa8c0e01058aeecb6..ca05b405e0b42a29447edf20409d4df43f15984c 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/flatbuffers.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/flatbuffers.h
@@ -16,8 +16,7 @@
 
 // clang-format off
 
-#ifndef FLATBUFFERS_H_
-#define FLATBUFFERS_H_
+#pragma once
 
 #include "base.h"
 
@@ -2483,5 +2482,3 @@ volatile __attribute__((weak)) const char *flatbuffer_version_string =
 }  // namespace flatbuffers
 
 // clang-format on
-
-#endif // FLATBUFFERS_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/stl_emulation.h b/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/stl_emulation.h
index 59666122a9a472e5a2ce42889c3ff9c43105e589..f3bfb93fe2061a6e170ee06f7ea64c04fc677e1c 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/stl_emulation.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/flatbuffers/stl_emulation.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef FLATBUFFERS_STL_EMULATION_H_
-#define FLATBUFFERS_STL_EMULATION_H_
+#pragma once
 
 // clang-format off
 
@@ -234,5 +233,3 @@ inline void vector_emplace_back(std::vector<T> *vector, V &&data) {
 #endif  // !FLATBUFFERS_CPP98_STL
 
 }  // namespace flatbuffers
-
-#endif  // FLATBUFFERS_STL_EMULATION_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/fwdi_forwarder_internal_generated.h b/Framework/LiveData/src/Kafka/private/Schema/fwdi_forwarder_internal_generated.h
index 47352549e8ddff7d634adb3c6949bcf65575b49f..b3768219368b8d4e47aff1b097ce7f423970c95d 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/fwdi_forwarder_internal_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/fwdi_forwarder_internal_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_FWDIFORWARDERINTERNAL_H_
-#define FLATBUFFERS_GENERATED_FWDIFORWARDERINTERNAL_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -184,5 +183,3 @@ inline bool Verifyforwarder_internalVector(flatbuffers::Verifier &verifier, cons
   }
   return true;
 }
-
-#endif  // FLATBUFFERS_GENERATED_FWDIFORWARDERINTERNAL_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/hs00_event_histogram_generated.h b/Framework/LiveData/src/Kafka/private/Schema/hs00_event_histogram_generated.h
index cb2b43fef9eef7b1ae824dc5276ab69184bd5a13..6c493177734a3abaa8dad98f1fd24f8e449a9742 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/hs00_event_histogram_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/hs00_event_histogram_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_HS00EVENTHISTOGRAM_H_
-#define FLATBUFFERS_GENERATED_HS00EVENTHISTOGRAM_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -799,5 +798,3 @@ inline void FinishSizePrefixedEventHistogramBuffer(
   fbb.FinishSizePrefixed(root, EventHistogramIdentifier());
 }
 }
-
-#endif  // FLATBUFFERS_GENERATED_HS00EVENTHISTOGRAM_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/is84_isis_events_generated.h b/Framework/LiveData/src/Kafka/private/Schema/is84_isis_events_generated.h
index 9c590c7e825b934a261cc76cf8872dd41624906e..df79562d5c0fadbbc1c4f0a07c1c7bf89e9c8a3d 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/is84_isis_events_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/is84_isis_events_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_IS84ISISEVENTS_H_
-#define FLATBUFFERS_GENERATED_IS84ISISEVENTS_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -109,5 +108,3 @@ inline flatbuffers::Offset<ISISData> CreateISISData(
   builder_.add_run_state(run_state);
   return builder_.Finish();
 }
-
-#endif  // FLATBUFFERS_GENERATED_IS84ISISEVENTS_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/tdct_timestamps_generated.h b/Framework/LiveData/src/Kafka/private/Schema/tdct_timestamps_generated.h
index b94f5e5816d52efcbc52f50ffb5b56669757db44..fcdc732224be2be942424753e3b2faa27b06e7e9 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/tdct_timestamps_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/tdct_timestamps_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_TDCTTIMESTAMPS_H_
-#define FLATBUFFERS_GENERATED_TDCTTIMESTAMPS_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -139,5 +138,3 @@ inline void FinishSizePrefixedtimestampBuffer(
     flatbuffers::Offset<timestamp> root) {
   fbb.FinishSizePrefixed(root, timestampIdentifier());
 }
-
-#endif  // FLATBUFFERS_GENERATED_TDCTTIMESTAMPS_H_
diff --git a/Framework/LiveData/src/Kafka/private/Schema/y2gw_run_info_generated.h b/Framework/LiveData/src/Kafka/private/Schema/y2gw_run_info_generated.h
index 73c52edc0b4ad08c8a8208a315e15f79b57d57b7..9ddc3e27a75fb17943e4f2446100493b92e751e1 100644
--- a/Framework/LiveData/src/Kafka/private/Schema/y2gw_run_info_generated.h
+++ b/Framework/LiveData/src/Kafka/private/Schema/y2gw_run_info_generated.h
@@ -2,8 +2,7 @@
 // automatically generated by the FlatBuffers compiler, do not modify
 
 
-#ifndef FLATBUFFERS_GENERATED_Y2GWRUNINFO_H_
-#define FLATBUFFERS_GENERATED_Y2GWRUNINFO_H_
+#pragma once
 
 #include "flatbuffers/flatbuffers.h"
 
@@ -393,5 +392,3 @@ inline void FinishSizePrefixedRunInfoBuffer(
     flatbuffers::Offset<RunInfo> root) {
   fbb.FinishSizePrefixed(root, RunInfoIdentifier());
 }
-
-#endif  // FLATBUFFERS_GENERATED_Y2GWRUNINFO_H_
diff --git a/Framework/LiveData/test/ADARAPacketTest.h b/Framework/LiveData/test/ADARAPacketTest.h
index 27662f4d9803679597e0e7b73a72d71a98a53858..3fad6ea886552210c8feec08818ec771c00896a0 100644
--- a/Framework/LiveData/test/ADARAPacketTest.h
+++ b/Framework/LiveData/test/ADARAPacketTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_ADARAPACKETTEST_H_
-#define MANTID_LIVEDATA_ADARAPACKETTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -288,5 +287,3 @@ private:
     return (((pulseId >> 32) == high) && ((pulseId & 0xFFFFFFFF) == low));
   }
 };
-
-#endif /* MANTID_LIVEDATA_ADARAPACKETTEST_H_ */
diff --git a/Framework/LiveData/test/ADARAPackets.h b/Framework/LiveData/test/ADARAPackets.h
index d3c3646d1e06ad48d7a82f1242cd4a49651218f0..c1411a7a5458cdbc7c540f448b1278d0969ab57f 100644
--- a/Framework/LiveData/test/ADARAPackets.h
+++ b/Framework/LiveData/test/ADARAPackets.h
@@ -4,13 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_ADARAPACKETS_H_
-#define MANTID_LIVEDATA_ADARAPACKETS_H_
-
-#ifndef MANTID_LIVEDATA_ADARAPACKETTEST_H_
-#error                                                                         \
-    "This file should only be included by MantidLiveData/test/AdaraPacketTest.h"
-#endif
+#pragma once
 
 // This file includes sample packets for the AdaraPacketTest unit test. It's
 // intended to be included by ADARAPacketTest.h (but outside of the class
@@ -310,5 +304,3 @@ const unsigned char devDesPacket[2600] = {
     0x2f, 0x70, 0x72, 0x6f, 0x63, 0x65, 0x73, 0x73, 0x5f, 0x76, 0x61, 0x72,
     0x69, 0x61, 0x62, 0x6c, 0x65, 0x73, 0x3e, 0x0a, 0x3c, 0x2f, 0x64, 0x65,
     0x76, 0x69, 0x63, 0x65, 0x3e, 0x0a, 0x00, 0x00};
-
-#endif /* MANTID_LIVEDATA_ADARAPACKETS_H_ */
diff --git a/Framework/LiveData/test/FakeEventDataListenerTest.h b/Framework/LiveData/test/FakeEventDataListenerTest.h
index 94217ce7cfc3b950a23fd611dc64735abb301f1b..fa488d9a96be29472c352aacf073655077ceba91 100644
--- a/Framework/LiveData/test/FakeEventDataListenerTest.h
+++ b/Framework/LiveData/test/FakeEventDataListenerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_FAKEEVENTDATALISTENERTEST_H_
-#define MANTID_LIVEDATA_FAKEEVENTDATALISTENERTEST_H_
+#pragma once
 
 #include "MantidAPI/LiveListenerFactory.h"
 #include "MantidDataObjects/EventWorkspace.h"
@@ -103,5 +102,3 @@ public:
 private:
   boost::shared_ptr<ILiveListener> fakel;
 };
-
-#endif /* MANTID_LIVEDATA_FAKEEVENTDATALISTENERTEST_H_ */
diff --git a/Framework/LiveData/test/FileEventDataListenerTest.h b/Framework/LiveData/test/FileEventDataListenerTest.h
index 1499b59d57a286522790a2315da2818d1596d39e..b44ef38218514572e10954cd9e8ef4aec4c4aed1 100644
--- a/Framework/LiveData/test/FileEventDataListenerTest.h
+++ b/Framework/LiveData/test/FileEventDataListenerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_FILEEVENTDATALISTENERTEST_H_
-#define MANTID_LIVEDATA_FILEEVENTDATALISTENERTEST_H_
+#pragma once
 
 #include "MantidAPI/LiveListenerFactory.h"
 #include "MantidDataObjects/EventWorkspace.h"
@@ -78,5 +77,3 @@ public:
     TS_ASSERT_THROWS(listener->extractData(), const std::runtime_error &)
   }
 };
-
-#endif /* MANTID_LIVEDATA_FILEEVENTDATALISTENERTEST_H_ */
diff --git a/Framework/LiveData/test/ISISHistoDataListenerTest.h b/Framework/LiveData/test/ISISHistoDataListenerTest.h
index 1aab075aa0e1bc5216593f917cc35f28213cee63..d2bf6a1516161f5427c5d9bf6575e92fb5cd927c 100644
--- a/Framework/LiveData/test/ISISHistoDataListenerTest.h
+++ b/Framework/LiveData/test/ISISHistoDataListenerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_ISISHISTODATALISTENERTEST_H_
-#define MANTID_LIVEDATA_ISISHISTODATALISTENERTEST_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -426,5 +425,3 @@ public:
 #endif
   }
 };
-
-#endif /* MANTID_LIVEDATA_ISISHISTODATALISTENERTEST_H_ */
diff --git a/Framework/LiveData/test/KafkaEventStreamDecoderTest.h b/Framework/LiveData/test/KafkaEventStreamDecoderTest.h
index ccee694011b962f8d849ceb88026907b98b40f38..6868ba59a2850896d9a40419f65e115498b57157 100644
--- a/Framework/LiveData/test/KafkaEventStreamDecoderTest.h
+++ b/Framework/LiveData/test/KafkaEventStreamDecoderTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_KAFKAEVENTSTREAMDECODERTEST_H_
-#define MANTID_LIVEDATA_KAFKAEVENTSTREAMDECODERTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -599,5 +598,3 @@ private:
   std::condition_variable m_callbackCondition;
   uint8_t m_niterations = 0;
 };
-
-#endif /* MANTID_LIVEDATA_KAFKAEVENTSTREAMDECODERTEST_H_ */
diff --git a/Framework/LiveData/test/KafkaHistoStreamDecoderTest.h b/Framework/LiveData/test/KafkaHistoStreamDecoderTest.h
index 4ebf592ae848061f28958534062218a77d89f413..bfe8bb97fec111f58dca8f8f5bc5f2a38d8f9d55 100644
--- a/Framework/LiveData/test/KafkaHistoStreamDecoderTest.h
+++ b/Framework/LiveData/test/KafkaHistoStreamDecoderTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_KAFKAHISTOSTREAMDECODERTEST_H_
-#define MANTID_LIVEDATA_KAFKAHISTOSTREAMDECODERTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -185,5 +184,3 @@ private:
   std::condition_variable m_callbackCondition;
   uint8_t m_niterations = 0;
 };
-
-#endif /* MANTID_LIVEDATA_KAFKAHISTOSTREAMDECODERTEST_H_ */
diff --git a/Framework/LiveData/test/KafkaTesting.h b/Framework/LiveData/test/KafkaTesting.h
index a214d0c3e38577117b27ba7e4c5e6423dbd32553..b13d76a6108ba15ad225300fbfb14ae64a241258 100644
--- a/Framework/LiveData/test/KafkaTesting.h
+++ b/Framework/LiveData/test/KafkaTesting.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_ISISKAFKATESTING_H_
-#define MANTID_LIVEDATA_ISISKAFKATESTING_H_
+#pragma once
 
 #include "MantidKernel/DateAndTimeHelpers.h"
 #include "MantidKernel/WarningSuppressions.h"
@@ -756,5 +755,3 @@ private:
   std::vector<int32_t> m_detid = {1001, 1002, 1100, 901000, 10100};
 };
 } // namespace KafkaTesting
-
-#endif // MANTID_LIVEDATA_ISISKAFKAEVENTSTREAMDECODERTESTMOCKS_H_
diff --git a/Framework/LiveData/test/KafkaTopicSubscriberTest.h b/Framework/LiveData/test/KafkaTopicSubscriberTest.h
index 4342a1534317ea8e17f46e8ca8aa40383914f635..4f01924026f7927f20e0da1e7ebb9269da535538 100644
--- a/Framework/LiveData/test/KafkaTopicSubscriberTest.h
+++ b/Framework/LiveData/test/KafkaTopicSubscriberTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_KAFKATOPICSUBSCRIBERTEST_H_
-#define MANTID_LIVEDATA_KAFKATOPICSUBSCRIBERTEST_H_
+#pragma once
 
 #include "MantidLiveData/Kafka/KafkaTopicSubscriber.h"
 #include <cxxtest/TestSuite.h>
@@ -36,5 +35,3 @@ public:
     TS_ASSERT_EQUALS(topic, subscriber->topics()[0]);
   }
 };
-
-#endif /* MANTID_LIVEDATA_KAFKATOPICSUBSCRIBERTEST_H_ */
diff --git a/Framework/LiveData/test/LiveDataAlgorithmTest.h b/Framework/LiveData/test/LiveDataAlgorithmTest.h
index 629fd22dd07effbd30575b56323f3e2d61f7c957..b4f761f06a6e04f51400f241371c28d22db1b705 100644
--- a/Framework/LiveData/test/LiveDataAlgorithmTest.h
+++ b/Framework/LiveData/test/LiveDataAlgorithmTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_LIVEDATAALGORITHMTEST_H_
-#define MANTID_LIVEDATA_LIVEDATAALGORITHMTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -137,5 +136,3 @@ public:
     }
   }
 };
-
-#endif /* MANTID_LIVEDATA_LIVEDATAALGORITHMTEST_H_ */
diff --git a/Framework/LiveData/test/LoadLiveDataTest.h b/Framework/LiveData/test/LoadLiveDataTest.h
index 95aedb8bf47331581b704fd9898b9671bdc120fb..7e20e02bbb5593439a56f9cd38fbdda0414a6ad6 100644
--- a/Framework/LiveData/test/LoadLiveDataTest.h
+++ b/Framework/LiveData/test/LoadLiveDataTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_LOADLIVEDATATEST_H_
-#define MANTID_LIVEDATA_LOADLIVEDATATEST_H_
+#pragma once
 
 #include "MantidAPI/FrameworkManager.h"
 #include "MantidAPI/LiveListenerFactory.h"
@@ -516,5 +515,3 @@ public:
     AnalysisDataService::Instance().clear();
   }
 };
-
-#endif /* MANTID_LIVEDATA_LOADLIVEDATATEST_H_ */
diff --git a/Framework/LiveData/test/MonitorLiveDataTest.h b/Framework/LiveData/test/MonitorLiveDataTest.h
index fe9ae43854722f1c84d64250aca33ea691433c11..c1be650ab509aa94bdde42bdd97e45900372a2cb 100644
--- a/Framework/LiveData/test/MonitorLiveDataTest.h
+++ b/Framework/LiveData/test/MonitorLiveDataTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_MONITORLIVEDATATEST_H_
-#define MANTID_LIVEDATA_MONITORLIVEDATATEST_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidKernel/Timer.h"
@@ -247,5 +246,3 @@ public:
     }
   }
 };
-
-#endif /* MANTID_LIVEDATA_MONITORLIVEDATATEST_H_ */
diff --git a/Framework/LiveData/test/SNSLiveEventDataListenerTest.h b/Framework/LiveData/test/SNSLiveEventDataListenerTest.h
index b2c98086c518454011cfbefb66c0b6e7ef57fe36..19e08de1481a4b9c56ffc580031dbc2e26a9cee9 100644
--- a/Framework/LiveData/test/SNSLiveEventDataListenerTest.h
+++ b/Framework/LiveData/test/SNSLiveEventDataListenerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_SNSLIVEEVENTDATALISTENERTEST_H_
-#define MANTID_LIVEDATA_SNSLIVEEVENTDATALISTENERTEST_H_
+#pragma once
 
 /* This code is largely based on Russell Taylor's test for the
  * FakeEventDataLister class. */
@@ -105,5 +104,3 @@ public:
 private:
   boost::shared_ptr<ILiveListener> sns_l;
 };
-
-#endif /* MANTID_LIVEDATA_SNSLIVEEVENTDATALISTENERTEST_H_ */
diff --git a/Framework/LiveData/test/StartLiveDataTest.h b/Framework/LiveData/test/StartLiveDataTest.h
index 61ec3723be8ecaccaae36c0bf97bb1950f84da63..2e4299377f8e2adb9340f2154c915f14103efc3a 100644
--- a/Framework/LiveData/test/StartLiveDataTest.h
+++ b/Framework/LiveData/test/StartLiveDataTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_STARTLIVEDATATEST_H_
-#define MANTID_LIVEDATA_STARTLIVEDATATEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -161,5 +160,3 @@ public:
 private:
   StartLiveData alg;
 };
-
-#endif /* MANTID_LIVEDATA_STARTLIVEDATATEST_H_ */
diff --git a/Framework/LiveData/test/TestDataListener.h b/Framework/LiveData/test/TestDataListener.h
index 88931547be9eef63404feda2b9ec184d707c251a..5949fa4ed8163ef964db31d5df6b2f7282546200 100644
--- a/Framework/LiveData/test/TestDataListener.h
+++ b/Framework/LiveData/test/TestDataListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_TESTDATALISTENER_H_
-#define MANTID_LIVEDATA_TESTDATALISTENER_H_
+#pragma once
 
 #include "MantidAPI/LiveListener.h"
 #include "MantidAPI/Run.h"
@@ -60,5 +59,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_TESTDATALISTENER_H_ */
diff --git a/Framework/LiveData/test/TestGroupDataListener.h b/Framework/LiveData/test/TestGroupDataListener.h
index 3dbe24d0f4fa690b65dd6c273f952ccc4fb2292c..e8d84dcc378feb345d0a69106c1d191f09cee068 100644
--- a/Framework/LiveData/test/TestGroupDataListener.h
+++ b/Framework/LiveData/test/TestGroupDataListener.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_LIVEDATA_TESTGROUPDATALISTENER_H_
-#define MANTID_LIVEDATA_TESTGROUPDATALISTENER_H_
+#pragma once
 
 //----------------------------------------------------------------------
 // Includes
@@ -49,5 +48,3 @@ private:
 
 } // namespace LiveData
 } // namespace Mantid
-
-#endif /* MANTID_LIVEDATA_TESTGROUPDATALISTENER_H_ */