We’ve all experienced smoke detectors that start to chirp, indicating the battery is failing. This past week, I played “chase the chirp” (there were several grouped in close proximity) and finally discovered an old detector hiding in plain sight above our basement stairway landing. I wondered, does it need new batteries or replacement?

How Old is Your Smoke Detector?

I was curious to see the age of all three smoke detectors in this area and discovered they were original to the house, or 25 years old! As I researched what’s changed in smoke detectors since 1999, I was reminded of the new standard that went into effect July 1, 2024 (UL 217 8th Edition) that established additional requirements for detectors. The standard calls for a new type of detector, currently implemented as a dual-sensor detector.  

A dual-sensor detector uses multiple detectors to detect both slow smoldering fires (best found with a photo-voltaic sensor) and flame fires (best found with an ionization sensor). A dual-sensor detector can sense a wider range of fires and offers added safety to residents. In addition, they can assist by reducing false alarms from a steam shower or a kitchen cooking malfunction.

 

dual sensor smoke detector

 

Is Your Smoke Detector Expired?

To tell if your smoke detector is expired, you can look for the following signs of age.

Smoke Detector Manufacturer’s Date

It is usually printed on the back of the smoke detector along with the serial number. If you can’t find the date, the alarm is old and needs to be replaced. Smoke detectors can become less sensitive over time, so even if they still seem to work, they may not be able to detect smoke in an emergency. 

 

how to determine age of your smoke detector

 

The 10-Year Rule

The US National Fire Protection Association (NFPA) issued NFPA Standard 72, National Fire Alarm and Signalling Code (2010 edition), which states: “Replace all smoke alarms, including those that use ten-year batteries and hard-wired alarms, when they are ten years old or sooner if they don’t respond properly when tested.”

Discoloration of Smoke Detector

Yellowing of the smoke detector is another sign of age and can be caused by exposure to heat, oxygen, and UV light. 

 

Discoloration or yellowing smoke detectors

Listen for the Chirp

A chirping alarm either needs a new battery or may need to be replaced. Lastly, if you press the “test” button and it doesn’t make a sound, the alarm may need to be replaced. 

Safety First

I now have six new detectors on their way to better protect my family from a wider range of fires. If it’s been a while, please check your smoke detector’s date code as I did. You may be surprised to learn it’s time for upgrades!