Index: trunk/ippMonitor/def/detProcessedExp_failure.d
===================================================================
--- trunk/ippMonitor/def/detProcessedExp_failure.d	(revision 19726)
+++ trunk/ippMonitor/def/detProcessedExp_failure.d	(revision 28043)
@@ -13,5 +13,5 @@
 ARGS  ARG1 basename=$detProcessedExp.path_base
 
-OP    OP1  $detProcessedExp.bg / $detProcessedExp.bg_stdev
+OP    OP1  $detProcessedExp.bg_stdev > 0.0 ? $detProcessedExp.bg / $detProcessedExp.bg_stdev : NAN
 
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