--- a/mod/quiz/accessrules.php
+++ b/mod/quiz/accessrules.php
@@ -3,6 +3,9 @@
  * This class keeps track of the various access rules that apply to a particular
  * quiz, with convinient methods for seeing whether access is allowed.
  */
+define('SECUREWINDOW', 1);
+define('SAFEBROWSER', 2);
+
 class quiz_access_manager {
     private $_quizobj;
     private $_timenow;
@@ -45,10 +48,10 @@ class quiz_access_manager {
             $this->_rules[] = $this->_passwordrule;
         }
         if (!empty($quiz->popup)) {
-            if ($quiz->popup == 1) {
+            if ($quiz->popup == SECUREWINDOW) {
                 $this->_securewindowrule = new securewindow_access_rule($this->_quizobj, $this->_timenow);
                 $this->_rules[] = $this->_securewindowrule;
-            } elseif ($quiz->popup == 2) {
+            } elseif ($quiz->popup == SAFEBROWSER) {
                 $this->_safebrowserrule = new safebrowser_access_rule($this->_quizobj, $this->_timenow);
                 $this->_rules[] = $this->_safebrowserrule;
             }
-- 
1.6.3.3