diff --git a/src/simulation/elements/POLO.cpp b/src/simulation/elements/POLO.cpp
index 26d51632b..b3b9e7bd1 100644
--- a/src/simulation/elements/POLO.cpp
+++ b/src/simulation/elements/POLO.cpp
@@ -30,7 +30,7 @@ Element_POLO::Element_POLO()
 	HeatConduct = 251;
 	Description = "Polonium, highly radioactive. Decays into NEUT and heats up.";
 
-	Properties = PROP_NEUTPASS|PROP_RADIOACTIVE|PROP_LIFE_DEC|PROP_DEADLY;
+	Properties = TYPE_PART|PROP_NEUTPASS|PROP_RADIOACTIVE|PROP_LIFE_DEC|PROP_DEADLY;
 
 	LowPressure = IPL;
 	LowPressureTransition = NT;