diff --git a/coffee/chosen.jquery.coffee b/coffee/chosen.jquery.coffee
index 6ebcfbd8703..2efa5c79c1d 100644
--- a/coffee/chosen.jquery.coffee
+++ b/coffee/chosen.jquery.coffee
@@ -141,7 +141,7 @@ class Chosen extends AbstractChosen
     this.results_reset(evt) if evt.target.nodeName is "ABBR" and not @is_disabled
 
   search_results_mousewheel: (evt) ->
-    delta = -evt.originalEvent.wheelDelta or evt.originalEvent.detail if evt.originalEvent
+    delta = evt.originalEvent.deltaY or -evt.originalEvent.wheelDelta or evt.originalEvent.detail if evt.originalEvent
     if delta?
       evt.preventDefault()
       delta = delta * 40 if evt.type is 'DOMMouseScroll'
diff --git a/coffee/chosen.proto.coffee b/coffee/chosen.proto.coffee
index 25c48ea8d5f..1450144c84f 100644
--- a/coffee/chosen.proto.coffee
+++ b/coffee/chosen.proto.coffee
@@ -137,7 +137,7 @@ class @Chosen extends AbstractChosen
     this.results_reset(evt) if evt.target.nodeName is "ABBR" and not @is_disabled
 
   search_results_mousewheel: (evt) ->
-    delta = -evt.wheelDelta or evt.detail
+    delta = evt.deltaY or -evt.wheelDelta or evt.detail
     if delta?
       evt.preventDefault()
       delta = delta * 40 if evt.type is 'DOMMouseScroll'