diff --git a/cleanup-pipeline.groovy b/cleanup-pipeline.groovy
index 282b041..cf6252e 100644
--- a/cleanup-pipeline.groovy
+++ b/cleanup-pipeline.groovy
@@ -33,7 +33,7 @@
     def env_vars
 
     // default STACK_TYPE is heat
-    if (!env.getEnvironment().containsKey("STACK_TYPE") || STACK_TYPE == '') {
+    if (!common.validInputParam(STACK_TYPE)) {
         STACK_TYPE = 'heat'
     }