diff --git a/Code/Mantid/Framework/MDAlgorithms/test/ConvertToDetectorFaceMDTest.h b/Code/Mantid/Framework/MDAlgorithms/test/ConvertToDetectorFaceMDTest.h
index 1446747ef8ae2d7fab7b51fea35eb2a91474a979..4fe0afeaf1ee928b9a24d6b43797e2f7dea5098b 100644
--- a/Code/Mantid/Framework/MDAlgorithms/test/ConvertToDetectorFaceMDTest.h
+++ b/Code/Mantid/Framework/MDAlgorithms/test/ConvertToDetectorFaceMDTest.h
@@ -77,6 +77,8 @@ public:
     TS_ASSERT(ws);
     if (!ws) return ws;
 
+    TS_ASSERT_EQUALS(ws->getNumExperimentInfo(), 1);
+
     for (size_t d=0; d<2; d++)
     {
       IMDDimension_const_sptr dim = ws->getDimension(d);