diff --git a/Code/Mantid/Framework/MDAlgorithms/src/ConvertSpiceDataToRealSpace.cpp b/Code/Mantid/Framework/MDAlgorithms/src/ConvertSpiceDataToRealSpace.cpp
index 803ac29a8f8f39dcd5a78e7ec940f65895f05dbf..67ff4e27ed8a420248b98863f09e1c9877b06579 100644
--- a/Code/Mantid/Framework/MDAlgorithms/src/ConvertSpiceDataToRealSpace.cpp
+++ b/Code/Mantid/Framework/MDAlgorithms/src/ConvertSpiceDataToRealSpace.cpp
@@ -708,7 +708,7 @@ IMDEventWorkspace_sptr ConvertSpiceDataToRealSpace::createMonitorMDWorkspace(
         atoi(thisWorkspace->run().getProperty("run_number")->value().c_str()));
 
     detid_t detindex = 0;
-    double signal = static_cast<float>(vecmonitor[iws]);
+    float signal = static_cast<float>(vecmonitor[iws]);
     float error = 1;
     if (signal > 1)
       error = sqrt(signal);