Househould Hazardous Waste
Special Wastes-  Smoke Detectors

Smoke Detectors

(Low Level Radioactive Material)

Uses:

 

Smoke detectors are an important life saving device that should be in every home.  There are essentially two types of smoke detectors available; these are the Photoelectric and Ionization smoke detectors.

Photoelectric smoke detectors use a beam of light to detect smoke.  When smoke enters the smoke detector chamber, it interrupts the beam of light and the smoke alarm goes off.

Ionization detectors work in much the same way but instead of a beam of light they use an electrical current created by a low level radioactive source (usually americium-241).  When smoke enters the smoke detector chamber it interrupts this electrical current and the smoke alarm goes off.

Ionization detectors are an extremely reliable and highly effective method of detecting even small amounts of smoke.  Their high reliability and effectiveness is due to the sensitive nature of the current created by the americium-241.  Although highly reliable, americium-241 is a low level radioactive source that must be properly handled and disposed of.

Americum-241 emits alpha radiation particles to create the electrical current used for detecting smoke.  Although the alpha exposure to humans is essentially zero (they are blocked in a few centimeters of air and/or the plastic case of the smoke detector), this low level radioactive source needs to be properly handled and disposed of. 

Handling and disposal:

 

• Do not remove, handle or cause americium-241 to become airborne.  Leave the entire smoke detector unit intact.

• Contact the manufacturer of your smoke detector for proper disposal information. CLICK HERE for a list of smoke detector manufacturers and their contact information (Special thanks to the County of Santa Barbara Public Works Department Resource Recovery & Waste Management Division for development of the manufacturers list) .