A smoke alarm that doesn't may or may not alert residents to fire over time, is the subject of a national recall.

The United States Consumer Product Safety Commission initiated the recall of Kidde NightHawk combination smoke/carbon monoxide alarms on Nov. 10.  The recall includes 3.6 million units in the U.S. and 1.5 million units in Canada.

The recall is happening as the alarm can fail to continue to chirp when it reaches its seven-year end of life, leading consumers to believe it is still doing it job. This is not good as it can fail to alert the consumer to a fire or carbon monoxide incident in their home.

 Alarms with the model number KN-COSM-IB and manufacture dates between June 1, 2004 and December 31, 2010 are affected by the recall.  To see more about the recall from the company go HERE.