Smoke detectors are one of the most important safety features of a home. Properly installed, working smoke detectors will provide the early warning needed to safely escape a fire. But how do you make sure the detectors are working? One important way is to replace them after 10 years as recommended by the National Fire Protection Association (NFPA).
As electronic devices, detectors are subject to random failures. Field studies indicate that about 3% (3 in 100) of older smoke detectors fail within the first year. After 30 years nearly all of the detectors will have failed, most years earlier. At 10 years there is roughly a 30% chance of failure of older units. National studies found home smoke detectors, when they fail, tend to fail totally as opposed to experiencing a simple loss of sensitivity. Regular monthly testing by pressing and holding the test button will help discover detector failure as well as a dead or missing battery. Replace detectors designed without a test button unless part of a security system.
Recent changes in detector design makes electronic failure much less likely than with older models.
BOTTOM LINE: Test all smoke detectors monthly and replace all units over ten years old.
During an Arizona home inspection, the inspector may not know the age of your smoke detectors, so it may be a good idea to have them replaced if they are older than 10 years old or if any fail the test button test.