diff --git a/gui/dialogs/random-failures.xml b/gui/dialogs/random-failures.xml
index 18334603e..2fdec4efe 100644
--- a/gui/dialogs/random-failures.xml
+++ b/gui/dialogs/random-failures.xml
@@ -31,9 +31,11 @@
           setprop("/sim/failure-manager/global-mcbf", m);
         };
 
+        props.globals.initNode("/sim/failure-manager/global-mtbf", 0);
+        props.globals.initNode("/sim/failure-manager/global-mcbf", 0);
+
         set_mtbf(getprop("/sim/failure-manager/global-mtbf"));
         set_mcbf(getprop("/sim/failure-manager/global-mcbf"));
-
       ]]>
     </open>
   </nasal>