diff --git a/README.md b/README.md
index cafc0e1..381895d 100644
--- a/README.md
+++ b/README.md
@@ -108,6 +108,7 @@ Example markup:
 
 ## History
 
+* 0.9.3 Changed `Number.isNaN` to use `!angular.isNumber` instead (original function not available in all browsers yet) (see [#2](/../../issues/2)).
 * 0.9.2 Fixed error when not defining `when-not-visible` attributes and updated NG Docs (see [#1](/../../issues/1)).
 * 0.9.1 Removed (incorrectly) namespaced events, not supported in JQ-Lite.
 * 0.9.0 Fixed event unbinding when removing bound elements from the DOM.
diff --git a/dist/angular-scroll-animate.js b/dist/angular-scroll-animate.js
index b03d774..24978e8 100644
--- a/dist/angular-scroll-animate.js
+++ b/dist/angular-scroll-animate.js
@@ -89,7 +89,7 @@ angular.module('angular-scroll-animate', []).directive('whenVisible', ['$documen
 
           var delayPercent = parseFloat(scope.delayPercent);
 
-          if ((Number.isNaN(delayPercent)) || (delayPercent < 0 || delayPercent > 1)) {
+          if (!angular.isNumber(delayPercent) || (delayPercent < 0 || delayPercent > 1)) {
             throw new Error('Directive: angular-scroll-animate \'delay-percent\' attribute must be a decimal fraction between 0 and 1.');
           }
         }
diff --git a/src/angular-scroll-animate.js b/src/angular-scroll-animate.js
index da58040..687d102 100644
--- a/src/angular-scroll-animate.js
+++ b/src/angular-scroll-animate.js
@@ -89,7 +89,7 @@ angular.module('angular-scroll-animate', []).directive('whenVisible', ['$documen
 
           var delayPercent = parseFloat(scope.delayPercent);
 
-          if ((Number.isNaN(delayPercent)) || (delayPercent < 0 || delayPercent > 1)) {
+          if (!angular.isNumber(delayPercent) || (delayPercent < 0 || delayPercent > 1)) {
             throw new Error('Directive: angular-scroll-animate \'delay-percent\' attribute must be a decimal fraction between 0 and 1.');
           }
         }