diff --git a/test/test.js b/test/test.js
index bbc3a5838..065679120 100644
--- a/test/test.js
+++ b/test/test.js
@@ -135,7 +135,7 @@
   var isStrict = ui.isStrict;
 
   /** Used to test Web Workers. */
-  var Worker = !(ui.isForeign || ui.isSauceLabs || isModularize) && document && root.Worker;
+  var Worker = !(ui.isForeign || ui.isSauceLabs || isModularize) && (document && document.origin != 'null') && root.Worker;
 
   /** Used to test host objects in IE. */
   try {