The life expectancy of a smoke detector corresponds directly with the length of its warranty. Inexpensive detectors need to be replaced every year, while others with five- or 10-year warranties should be replaced once the warranty has expired. Properly disposing of obsolete smoke detectors is important. There are two basic types of smoke detectors: photoelectric and ionization chamber. Photoelectric smoke detectors can be easily disposed of in the recycling or trash bin, but ionization chamber detectors contain a small amount of radioactive americium 241 and need to be disposed of accordingly.

Smoke detectors that contain radioactive material are required to have a yellow international radiation symbol affixed to the unit. This symbol is typically found on the back of the detector and looks like a three-bladed fan on a yellow background with a large dot in the middle. If the detector does not have the symbol on it and it does not appear as though the symbol has been removed, it is safe to assume that there is no radioactive material in the detector, and the detector can be disposed of in the recycling or trash bin.

Proper disposal of ionization chamber smoke detectors containing radioactive material varies from state to state. Kansas does not have a regulated disposal policy for ionization chamber smoke detectors, so those detectors can also be disposed of in the regular trash bin. Remove the batteries from the detector and seal the detector in a plastic bag before disposing of it.

When possible, however, the safest way to dispose of an ionization chamber smoke detector is to package it up and mail it back to the manufacturer. Call the manufacturer to obtain proper shipping instructions before mailing any package. Label the outside of the box “For Recycling” when returning detectors to the manufacturer. The United States Postal Service maintains a list of smoke detector manufacturers and their addresses on the USPS website at about.usps.com.

Curie Environmental Services in Albuquerque, N.M. will recycle all brands of smoke detectors for a fee. Visit their website at curieservices.com for pricing and information on shipping the detectors to them.

However you choose to dispose of them, never disassemble ionization chamber detectors. Disassembling could result in radioactive contamination.

— Have a home improvement question for Fix-It Chick? Email it to Linda Cottin at hardware@sunflower.com.