This is a Canadian model (thus the French), but every CO detector should have a manufactured date on the back. Check it, and when the detector is getting old, replace it. Photo by Brad Moon.
We’re still a month away from the November 4 ‘fall back’ where states (and provinces) that participate in Daylight Savings Time set their clocks back one hour. Besides celebrating a welcome hour of additional sleep, this is traditionally the time when people are encouraged to swap out the batteries in their smoke detectors. This is an excellent idea. I recently had an experience that’s resulted in adding another safety item to my twice-yearly DST checklist: checking the manufacturing date on our carbon monoxide detectors.
Like many homeowners, I bought CO detectors when we moved in, installed them on each floor of the house — and near the bedrooms — then pretty much forgot about them, other than the odd vacuuming to keep them clean and a passing glance to make certain the status light was green. Many CO detectors are plug-in or hard-wired (some with a battery back-up in case of power failure), so changing batteries isn’t the same concern as with smoke detectors.
However, they do have a ‘best before’ date. Of course I realized this when I bought them, but time has a way of passing quickly.
We re-discovered the fact a few days ago. I was working in the house, my daughter was home from school, complaining of a headache. One of the CO detectors went off. It wasn’t the single beep that indicates a known malfunction, it was the four beeps that indicate a real alarm. Maybe it was dirty? There were no gas appliances running and the fireplace wasn’t in use — therefore there were no sources of combustion in the house. I blew it out carefully with some compressed air, plugged it back in and ran the test cycle. Everything seemed fine. An hour later, a second CO detector went off. This was getting weird, but I went through the same routine, then opened a few windows, just in case. Everything was normal for a few hours. I wasn’t feeling groggy or anything that might make me suspect a problem. The other kids got home from school, my wife got home from work, we ate dinner, then the CO detectors went off again. Clearly, there was something going on and it was time to stop second guessing. We called the fire department. They asked if anyone had a headache and I immediately thought of my daughter. However, she was running around playing tetherball, so I declined the ambulance offer.
A few minutes later, everyone was in the backyard (including the dogs), the windows were closed and the fire truck arrived. The team was pretty cool, since this wasn’t an emergency. While a trio of firemen went in the house with carbon monoxide detectors, the driver invited my boys in to explore the truck.
After inspecting the house, the firemen gave us the all clear. Their readings were zero — not even trace amounts. Which makes sense given that there were no gas appliance running and we don’t have a garage. Although it seems like an incredible coincidence, it appeared that two CO detectors reached end-of-life on the same day. The third was fine. Inspection of the units that were sounding off showed a manufacturing date that is approaching the ‘best before’ date when they should be replaced. The firemen pointed out that this is a common problem and people frequently forget that they need to replace these detectors every five years or so (or sooner, depending on the model). They also made the point that it is that manufacture date, not the purchase date, that counts.
Carbon monoxide is invisible, colorless, tasteless, odorless and deadly; it’s even more dangerous for infants and children. That’s why it’s earn the nickname of ‘the silent killer’ and according to the CDC, it’s earned that title: between 199 and 2004, unintentional CO poisoning unrelated to fires claimed an average of 439 U.S. lives yearly. It’s also a relatively light gas that rises and is easily distributed throughout a home through heating/cooling ducts. All it takes is a gas furnace with a blocked vent or cracked heat exchanger or even fumes from running a car or lawn mower in an attached garage to begin poisoning home occupants.
Because you can’t see or smell the gas as it fills a home, a working CO detector is your only real defense against it (of course you should also make sure gas appliances and fireplaces are properly maintained). So when it’s time to fall back (and then to leap forward), after you swap out your smoke detector batteries, flip over your CO detectors to see if they’re getting old. I was lucky and the malfunctioning units gave false alarms, but they could have simply stopped working. And if you don’t have a CO detector, grab one now. They’ve come down in price in recent years and you can now buy a decent plug-in version for twenty bucks, which is cheap peace of mind.
