diff --git a/date_api/date_api.module b/date_api/date_api.module
index d85a8a5..8dc2cba 100644
--- a/date_api/date_api.module
+++ b/date_api/date_api.module
@@ -403,7 +403,7 @@ class DateObject extends DateTime {
    *   A single date part.
    */
   public function removeGranularity($g) {
-    if ($key = array_search($g, $this->granularity)) {
+    if (($key = array_search($g, $this->granularity)) !== FALSE) {
       unset($this->granularity[$key]);
     }
   }