Residents Cautioned to Reduce Risk of Carbon Monoxide Exposure

February 2 2026
• After carbon monoxide exposure in Needham sent two people to the hospital, the fire department and a local health expert discuss how families can stay safe.

Needham Fire Chief Tom Conroy calls carbon monoxide “the silent killer.” The gas is odorless, tasteless, colorless and poisonous.

“It can sneak up on you,” he said. “With carbon monoxide, depending on the concentration, it only takes a couple of breaths to impair you.”

On Tuesday, two construction workers at a new build on Tolman Street were found unresponsive in the home after exposure to the deadly gas. One was taken to Beth Israel Deaconess Hospital-Needham with serious injuries, while the other was intubated and put on a ventilator in a Boston hospital, Conroy said.

Upon arrival to the scene, Conroy said CO detectors were sounding, and his crews determined the heating system had somehow malfunctioned. Carbon monoxide can be produced by gas- and oil-burning furnaces, charcoal grills, portable generators and other fuel-burning appliances.

The winter months increase residents’ risks of carbon monoxide exposure, as dormant furnaces are switched on and generators are started up during power outages or storms, such as the one that recently dumped nearly two feet of snow. People may also warm their cars up in the garage, which could set off detectors, Conroy said.

“As we get into the wintertime and people’s heating systems kick on, they may not have had them serviced and they’re not burning cleanly,” he said. “We’ve run into quite a bit of times where people put generators in their garage and started them up, and it’s just not enough ventilation. The generator should be at least 15 feet away from the house.”

His department can receive up to five calls a day for carbon monoxide, some of which are false alarms but “many of them are viable alarms,” he said.

What makes carbon monoxide exposure potentially tricky to identify is the way it presents as the flu or a cold, said Dr. Cliff Berger, chief of cardiology at BID-Needham. Symptoms can be nonspecific, Berger said, the most common of which are headache, drowsiness, nausea and dizziness. In more severe cases, people can become confused, short of breath, experience chest pain or pass out, he said.

Carbon monoxide reduces the body’s oxygen levels. Typically, hemoglobin in red blood cells brings oxygen from the lungs to our tissues, but in the event of carbon monoxide poisoning, CO will preferentially bind to the hemoglobin instead of oxygen, thus displacing it, Berger said.

The Needham Fire Department uses CO detectors to measure levels within a home, and Berger said medical personnel can administer a blood test to measure carboxyhemoglobin, which, when above a certain level, indicates carbon monoxide poisoning.

“Obviously you have to have a suspicion for this. We do see lots of flu and viral infections this time of year,” he added, “so you have to think of it, and it has to be the right scenario where you think of it.”

Conroy said newer homes typically have more efficient systems, meaning they receive fewer calls of concern. In the event of a CO leak, fire crews will launch an investigation into the source, after which Eversource or another private contractor will remediate the issue. For new homes and homes that exchange hands, Conroy said the NFD will conduct inspections.

He advised residents to be diligent about checking their detectors.

“Make sure you have a carbon monoxide detector on every level of the home. Test it monthly, change the batteries in the device when we change our clocks,” Conroy said. “If they do go off, get out of the house and call 9-1-1 immediately.”

Opening windows, leaving the home and getting away from the source is important, Berger said. Having CO detectors “saves lives,” he said.

People should also be mindful about how they’re using appliances and running their cars, Berger said.

“With this time of year particularly, when there’s power failures and people are using home generators, make sure that they’re using them in well-ventilated spaces, that they’re not using any gas-powered appliances in a closed space or in an area near air intake in your home,” he said. “Idling your car where the exhaust is either in a garage that’s not well-ventilated or in an area where there’s air intake can be dangerous.”