Know the facts about carbon monoxide poisoning

The February blizzard that wreaked havoc across Cape Cod highlighted the need for residents to be aware of the dangers of carbon monoxide (CO) poisoning. When the power goes out during cold weather, staying warm becomes our greatest concern, which is why it’s so important to know how to do it safely.

In addition to the eight people in Provincetown who were involved in a mass casualty incident involving CO poisoning aboard a fishing vessel on Feb. 26, at least 10 others were brought to the Cape Cod Hospital Emergency Department on the night of the storm on Feb. 23 with signs of poisoning from the odorless gas.

To diagnose CO poisoning, doctors measure carboxyhemoglobin, which is the percentage of hemoglobin that is bound to carbon monoxide, according to Cape Cod Hospital emergency medicine physician Michael Hall, MD, MPH. Acute exposures with levels over 10 percent are considered toxic, he said.

“Carbon monoxide binds the hemoglobin with over 200 times greater affinity than oxygen,” he explained. “So, it displaces oxygen from the hemoglobin and then your blood isn’t able to deliver oxygen to the tissues. The antidote is 100 percent oxygen, and, in severe cases, they can actually put people in a dive chamber and do a hyperbaric oxygen, which is a high percentage of oxygen plus high pressure.”

The 10 cases Dr. Hall saw at Cape Cod Hospital on the night of the storm were all treated with high-flow oxygen for several hours. No one had a level of carboxyhemoglobin (over 25 percent) that would have triggered a transfer to Mass General Brigham for hyperbaric treatment.

“The common symptoms are headache, nausea and dizziness, but once people become confused or pass out, then it becomes very dangerous,” he said. “Fortunately, it’s reversible in most cases.”

Feels Like the Flu

Part of the problem with carbon monoxide poisoning is that the symptoms mimic the flu, so when people are exposed to it in the winter months, they might not think about carbon monoxide poisoning, said Fire Prevention Officer Scott Romer at the Brewster Fire Department.

“Carbon monoxide is colorless, odorless and tasteless,” he said. “A lot of times it’s referred to as the silent killer because there is no way to detect it without a detector.”

In Massachusetts, the law requires a CO detector on every floor of your home and one within 10 feet of every bedroom, he said. Unfortunately, not all people are aware of those laws because the Cape has so many summer homes with residents who live in other states that might not have the same law, he added.

Just about anything that burns any type of fossil or carbon-based fuel has the potential to create carbon monoxide, Romer said. That includes gasoline, diesel, kerosene, propane, coal and wood.

“It’s a product of incomplete combustion, so anything from your gas grill to your wood fireplace or woodstove have the capability of producing carbon monoxide,” he said. “Where we run into problems is when it’s not properly ventilated.”

Generators, Furnaces, Cars and Blocked Vents

A common culprit is a generator that is running in a confined space like a garage or basement. All generators need to be outside and Romer cautioned that people need to keep the wind direction in mind as well, because it could be blowing in some kind of opening.

“The other big one that we see is improperly installed heating equipment like your furnaces and boilers,” he said. “The issues we usually see with those are a failure of the venting system or a lack of maintenance, so the recommendation is that any installed heating equipment get serviced by a certified professional at least annually. That ensures that it’s burning clean. The cleaner it burns, the more complete the combustion is and the less the risk of carbon monoxide.”

Romer also cautions people to make sure their vents are clear and not blocked by snow. Some of the newer high-efficiency units have vents that are very close to the ground and at risk of being blocked by snow drifts.

Car exhaust is another danger. Cars should never be run inside a garage. In snowy weather, it’s important to make sure the exhaust pipe is not covered with snow when outdoors. During the February storm, a 21-year-old college student in Newport, R.I., died from carbon monoxide poisoning while sitting in his car charging his cell phone. Even if your exhaust pipe is not blocked, it’s not safe to sit in a running parked car for very long even if you are outdoors, Romer said.

“Another thing people will attempt to do sometimes is heat their house with some sort of gas oven or stove,” he said. “That has the potential to create a carbon monoxide situation if you’ve got the oven door open or you’re running it for a long period of time. It doesn’t have the time to vent properly. It’s very common for people to say, ‘We have gas, so we’ll open the oven to heat the house,’ so that’s another risk factor.”

Gas camping stoves, charcoal grills and Coleman lanterns should also never be used inside the house.

When Your Detector Goes Off

If your carbon monoxide detector goes off, you need to get out of the house as soon as possible and call your local fire department, Romer said. They have equipment that is much more sensitive than home detectors that can detect lower levels of carbon monoxide.

“We try to find out if it’s actually an issue or a faulty detector, but you should never, ever assume it’s a faulty detector until we come out and check it,” Romer said.

A Year-Round Concern

Winter isn’t the only time people risk getting carbon monoxide poisoning.

“Really, it’s a year-round threat, but there is always a bump when we have any kind of power outage from an extended winter storm,” Romer said. “People are trying to think of anything they can do to warm up.”