Here in Port St. Lucie, the step stool comes out every fall. As of late September 2026, with Fire Prevention Week coming up in October, plenty of us will do what I did for years: pull the smoke alarm off the ceiling, push in a fresh battery, press the test button, hear the beep, done for another year.
It feels like maintenance. I came down from Jersey thinking an alarm was an alarm, and as long as it chirped when the battery died, it was working. The northern house logic does not help you here, and neither does the beep.
What the U.S. Fire Administration says
The U.S. Fire Administration puts it plainly: “Age matters when it comes to smoke alarms. They need to be replaced 10 years from the manufacture date.” Not the battery. The whole unit, counted from the day it was made, not the day you screwed it to the ceiling.
Why a new battery doesn’t reset the clock
The part that wears out is the sensor. Dust and cobwebs settle into the sensing chamber year after year, and that buildup makes it harder for the alarm to detect smoke, however fresh the battery is.
The test button won’t tell you. It only confirms that the battery, the electronics and the horn work. It does not tell you the smoke sensor still does its job. So an old unit can pass the beep test every October while the one part you bought it for quietly gives out…