Photo: Non-working fire alarms were a likely factor in the death of a Belmont resident last month.

A pair of non-working residential fire alarms were a likely factor resulting in the death of a woman on Birch Hill Road last month, according to Belmont and State Fire officials.

While the cause of the 4 a.m. blaze on April 24 officially remains “undetermined,” it appears the fire was accidental, said Belmont Fire Chief David Frizzell and State Fire Marshal Peter Ostroskey in a joint statement on May 8.

“Fire investigators determined the fire started in the kitchen. They found no signs of an intentionally set fire. There was evidence of several potential accidental causes, but not enough to narrow it down to one most probable cause. Therefore, the fire will remain officially undetermined,” said the release.

Middlesex District Attorney Marian Ryan has identified the victim as Alison Bane, 55, who was the only occupant of the house. Bane, who previously lived in Arlington and Maine, graduated from Boston College in the 1980s with a BA and a law degree and practiced in Maine. The house is owned by a trust in her parents’ name.

There was one minor firefighter injury. A cat was rescued from the house and is being taken care of. Damage to the split-level single-family home is estimated at $150,000.

Frizell said first arriving firefighters did not hear any smoke alarms sounding. During the investigation, one battery-operated alarm on the lower level of the home had no battery and appeared to be of 1980s vintage. Pieces of a similar style smoke alarm were found on the second floor, but it may not have actually been installed. There were no carbon monoxide alarms in the home.

“It is important to replace smoke alarms … every ten years. Like every other appliance in your home, they do not last forever,” said Frizzell. “Time is your enemy in a fire where you may have less than three minutes to escape. Expired alarms cannot be counted on to work in a fire.”

Ostroskey said the Belmont incident was the second fatal fire in April where the smoke alarms were decades old and failed to work when residents needed them most.

“I urge everyone to take the time this spring to ensure all smoke alarms that need them to have fresh batteries and replace any alarms that are more than 10 years old.” he added.

“Ask yourself, ‘when did I last replace these smoke alarms? Were they here when I moved in?’ Smoke alarms made in the last decade have a date stamped on them. Older alarms do not.”

Investigators from the Belmont Fire and Police Departments and State Police assigned to the Office of the State Fire Marshal and to the Office of the Middlesex District Attorney jointly investigated the fire. The Department of Fire Services’ Code Compliance Unit provided assistance.

For more information on smoke alarms, go to: https://www.mass.gov/service-details/smoke-and-carbon-monoxide-alarms