diff --git a/src/moab/MPBSI.c b/src/moab/MPBSI.c
index 19ce61e..cbb4ff8 100644
--- a/src/moab/MPBSI.c
+++ b/src/moab/MPBSI.c
@@ -3179,6 +3179,8 @@ int MPBSNodeUpdate(
       {
       MUStrCpy(tmpBuffer,AP->value,sizeof(tmpBuffer));
 
+      memset(N->FBM,0,sizeof(N->FBM));
+
       ptr = MUStrTok(tmpBuffer,", \t",&TokPtr);
 
       while (ptr != NULL)