diff --git a/CLDConfig/cld_arc_steer.py b/CLDConfig/cld_arc_steer.py
index 32147ff..6265864 100644
--- a/CLDConfig/cld_arc_steer.py
+++ b/CLDConfig/cld_arc_steer.py
@@ -64,3 +64,6 @@ def setupCerenkov(kernel):
         )
 SIM.filter.mapDetFilter["ARCBARREL"] = "opticalphotons"
 SIM.filter.mapDetFilter["ARCENDCAP"] = "opticalphotons"
+
+# explicitly use the cylinder volume base particle handler
+SIM.part.userParticleHandler = "Geant4TCUserParticleHandler"