Abstract: Both an apparatus and method for testing smoke detector operation is provided. The apparatus and method is used to either standardize conventional smoke detectors, or to test the actuation of an alarm signal for smoke detectors. In one embodiment of the invention, a standard dispenser is used which contains a liquid suspension of substantially uniformly sized latex particulates which are introduced into the smoke detector. The substantially uniformly sized latex particulates enter the smoke detector and simulate combustion product particulates. The uniformly sized latex particulates are used to actuate an alarm signal for a conventional smoke detector to test the smoke detector operation. In this manner, there is provided both a system and a method of testing smoke detectors which does not leave a residue on or in the smoke detectors and advantageously does not effect the operation or operating life of a smoke detector.