Fire departments on Whidbey are seeing an increase in carbon monoxide related calls, but often it’s just that the batteries or sensors in the carbon monoxide detectors have expired.

Oak Harbor Fire Chief Ray Merrill attributes the increase in carbon monoxide calls to a law passed in 2013 requiring existing apartments, condominiums, hotels, motels and single-family residences to install carbon monoxide detectors.

“Many people purchased and installed carbon monoxide alarms at that time,” Merrill said in a press release.

Merrill said most detectors have a 7- to 10-year lifespan and are starting to expire. He estimates his department has received about two dozen calls in the past six months related to carbon monoxide detectors.

“The irony is carbon monoxide alarms do not detect the presence of carbon monoxide when in end-of-life mode, and if carbon monoxide gas was present, the alarm may not activate,” Merrill said.

He said residents should check the expiration date of their detectors before calling, but added that residents should never hesitate to call if they are unsure.

South Whidbey Fire/EMS Deputy Chief of Operations Terry Ney said his department has also seen a rise in carbon monoxide calls.

“It’s just the end of life of the detectors, not indicative of an increase in carbon monoxide,” Ney said. He added that his department will still respond to calls and verify if there is any harmful gas.