diff --git a/src/main/java/org/gcube/smartgears/extensions/resource/HealthResource.java b/src/main/java/org/gcube/smartgears/extensions/resource/HealthResource.java
index ef18a62..cf12869 100644
--- a/src/main/java/org/gcube/smartgears/extensions/resource/HealthResource.java
+++ b/src/main/java/org/gcube/smartgears/extensions/resource/HealthResource.java
@@ -82,7 +82,8 @@ public class HealthResource extends ApiResource {
 	}
 
     public void stop() {
-    	timer.cancel();
+    	if (timer!=null)
+    		timer.cancel();
     }
 
 	@Override