How long do CO and CO/Smoke combo alarms last?

ANSI/UL2034 specifications have changed to require all CO alarms and combination smoke/CO alarms to have an end of life feature. This is an industry wide change. This requirement went into effect for any production beginning on August 1, 2009. All BRK/First Alert carbon monoxide alarms manufactured on or after this date meet this requirement. This information is stated on the original packaging, label on the alarm and the manuals.

Recent breakthroughs in CO sensor technology and alarm design improvements allow most BRK CO alarms and combination smoke and CO alarms to a have a 10-year alarm life, a 10-year CO sensor life, and a 10-year warranty. Many also have batteries that last for 10 years. The end of life timer built into the alarm is a simple counter that begins working once the unit is activated either by plugging it in, hardwiring or inserting the battery. Then after approximately 120 months of operation (or other timing as coded in the alarm which may be 60 or 72 months) the unit will begin to sound 5 chirps. See the individual CO product on the BRK website and click on the ”sounds” tab to hear this alert. This silence feature can temporarily quiet the End of Life warning “chirp” for up to 2 days. You can silence the End of Life warning “chirp” by pressing the Test/Silence button. The horn will chirp, acknowledging that the End of Life feature has been activated. After approximately 2 days, the End of Life “chirp” will resume. After approximately 2-3 weeks the End of Life warning cannot be silenced