diff --git a/src/Physics/NuclearState/NuclearModelMap.cxx b/src/Physics/NuclearState/NuclearModelMap.cxx
index c31e176ab..0dd515e1b 100644
--- a/src/Physics/NuclearState/NuclearModelMap.cxx
+++ b/src/Physics/NuclearState/NuclearModelMap.cxx
@@ -155,7 +155,9 @@ void NuclearModelMap::LoadConfig(void)
   for(RgIMap::const_iterator it = entries.begin(); it != entries.end(); ++it){
     const std::string& key = it->first;
     // Does it start with the right string?
-    if(key.compare(0, keyStart.size(), keyStart.c_str()) == 0){
+    // Edit: Protect from descending keys (NuclearModel@Pdg should not descend into subalgs)
+    if( (key.compare(0, keyStart.size(), keyStart.c_str()) == 0) &&
+	(key.find("/") == std::string::npos) ){
       // The rest is the PDG code
       const int pdg = atoi(key.c_str()+keyStart.size());
       const int Z = pdg::IonPdgCodeToZ(pdg);