diff --git a/Calorimeter/CaloGeoHelpers/CaloGeoHelpers/ATLAS_CHECK_THREAD_SAFETY b/Calorimeter/CaloGeoHelpers/CaloGeoHelpers/ATLAS_CHECK_THREAD_SAFETY
new file mode 100644
index 0000000000000000000000000000000000000000..056c0eb3a2bc6c413719689e8a2772cf24674024
--- /dev/null
+++ b/Calorimeter/CaloGeoHelpers/CaloGeoHelpers/ATLAS_CHECK_THREAD_SAFETY
@@ -0,0 +1 @@
+Calorimeter/CaloGeoHelpers