If you find that within the span of an hour or so, all of the carbon monoxide detectors you dutifully installed in your house start going off with double-beep alarms, there are two possibilities:
- There’s carbon monoxide in the house and you’re going to die
- You installed your detectors seven years ago and it’s time for them to jointly commit suicide
Odds are it’s the latter. Apparently there is actually some kind of a detector molecule or thingamajig that degrades over time, and seven years after being powered up they turn into pumpkins. Nothing you can do except throw them away.
The main question now is whether to buy new ones or not.