Smoke Detector with (490-0466) Care and Maintenance Faxback Doc. # 15980 Silence Control The smoke detector is virtually maintenance free. However, under dusty conditions, a vacuum hose may be used to clear the sensing chamber of dust. REPAIR AND SERVICES The smoke alarm uses a very small amount of radioactive element which is safely contained within the chamber assembly. If the smoke detector is defective in any way, do not taper with the unit. Return the unit for servicing. There will be a service charge for repairing out of warranty units. (ALL-07/19/95)