diff --git a/Event/EventOverlay/EventOverlayJobTransforms/share/skeleton.OverlayBS_tf.py b/Event/EventOverlay/EventOverlayJobTransforms/share/skeleton.OverlayBS_tf.py
index 29e7b85402215446198ab356d94e3c2ac28673ed..aad1b7fcd97d9195a77694829d757181a0cb9363 100644
--- a/Event/EventOverlay/EventOverlayJobTransforms/share/skeleton.OverlayBS_tf.py
+++ b/Event/EventOverlay/EventOverlayJobTransforms/share/skeleton.OverlayBS_tf.py
@@ -168,6 +168,18 @@ else:
     #DetFlags.overlay.LAr_setOff()
     DetFlags.overlay.Truth_setOn()
 
+## Tidy up NSW DetFlags: temporary measure
+DetFlags.sTGC_setOff()
+DetFlags.Micromegas_setOff()
+from AtlasGeoModel.CommonGMJobProperties import CommonGeometryFlags
+if (CommonGeometryFlags.Run() in ["RUN3", "RUN4"]):
+    DetFlags.sTGC_setOn()
+    DetFlags.Micromegas_setOn()
+
+from AtlasGeoModel.MuonGMJobProperties import MuonGeometryFlags
+if not MuonGeometryFlags.hasCSC():
+    DetFlags.CSC_setOff()
+
 DetFlags.Print()
 
 include ( "RecExCond/AllDet_detDescr.py" )
diff --git a/Event/EventOverlay/EventOverlayJobTransforms/share/skeleton.OverlayPool_tf.py b/Event/EventOverlay/EventOverlayJobTransforms/share/skeleton.OverlayPool_tf.py
index e57b2fa09273554d0a3be1f27a7e4d6a488c2bd4..80084846a2b2b77750f3495b69f1aab7248a9a6a 100644
--- a/Event/EventOverlay/EventOverlayJobTransforms/share/skeleton.OverlayPool_tf.py
+++ b/Event/EventOverlay/EventOverlayJobTransforms/share/skeleton.OverlayPool_tf.py
@@ -90,6 +90,18 @@ else:
 
     DetFlags.digitize.LVL1_setOff()
 
+## Tidy up NSW DetFlags: temporary measure
+DetFlags.sTGC_setOff()
+DetFlags.Micromegas_setOff()
+from AtlasGeoModel.CommonGMJobProperties import CommonGeometryFlags
+if (CommonGeometryFlags.Run() in ["RUN3", "RUN4"]):
+    DetFlags.sTGC_setOn()
+    DetFlags.Micromegas_setOn()
+
+from AtlasGeoModel.MuonGMJobProperties import MuonGeometryFlags
+if not MuonGeometryFlags.hasCSC():
+    DetFlags.CSC_setOff()
+
 DetFlags.Print()
 
 globalflags.DataSource.set_Value_and_Lock('geant4')