When temperatures fall, carbon monoxide dangers rise

COMonitor_bloglargeYou can’t see it, smell it or taste it. But carbon monoxide is a dangerous, deadly gas. When temperatures start to cool and furnaces, space heaters and fireplaces are put to use, that’s when we see more people come into our emergency department with carbon monoxide (or CO) poisoning.

Inhaling CO is toxic because the gas takes the place of oxygen in hemoglobin in our blood. Hemoglobin delivers oxygen in the body. CO also binds a lot stronger than oxygen, so it’s stubborn and you have to flood the system with oxygen to wash it out. 

Many sources can cause CO poisoning because it’s a common byproduct of combustion. The gas can accumulate when burning materials (wood, charcoal, kerosene) or using gas-powered equipment and engines without proper ventilation. Gas furnaces can malfunction and allow fumes to collect in a building. Sometimes animals can nest in a ventilation system and prevent fumes from escaping.


Unfortunately, there isn’t one key symptom of CO poisoning. There are several non-specific symptoms such as headache, fatigue, dizziness, feeling lightheaded and confusion. As it gets more serious, you might experience nausea, vomiting, numbness or tingling, weakness and, ultimately, pass out. Continued exposure would cause the heart to stop.

The symptoms during initial or mild exposure can seem like the flu, but the key difference is there is no fever or overall body aches. Additionally, unlike the flu, symptoms will improve if you get fresh air.

What to do

If you suspect CO poisoning or you have a detector that has sounded an alarm, get out. Go outside to fresh air and call 911. The fire department has hand-held monitors that can detect and measure the amount of CO present, and paramedics can begin medical care.

If you come into a home or building where people may have been exposed, your brief exposure to help them outside to safety can be tolerated.


The primary goal is to release the CO out of the blood as quickly as possible. It can cause damage to the heart, lungs, brain and kidneys. Severe or prolonged exposure can also cause lasting neurocognitive effects. Pregnant women, their fetuses and people with significant chronic disease are more at risk when exposed to CO.

If you simply remove yourself from the area and go outside, it would take about 300 minutes (five hours) to reduce your CO level by half, and longer to get it completely out of your system. If you use an oxygen mask from paramedics or the emergency department, it would take about 100 minutes (1.6 hours) to reduce it by half. 

Here at Ohio State Wexner Medical Center, we have six hyperbaric oxygen chambers that provide high levels of oxygen at increased pressure. This pushes oxygen in and carbon monoxide out at a much faster rate. We use hyperbaric oxygen therapy to treat CO poisoning as well as other conditions including serious infections, burns, wound healing and decompression sickness.


The best way to avoid CO poisoning is to prevent it. Maintain gas furnaces and ventilation systems. Make sure you have good ventilation when using fireplaces or space heaters. Using gas-powered tools indoors or in a garage also requires proper ventilation. Never warm up a car in an attached garage – even with the door open, fumes can seep through the walls and ceiling into the home.

Finally – just like smoke detectors, I believe a carbon monoxide detector is a must. It’s a simple way to identify a potential killer and keep you and your family safe.                                                                                                                                   
Daniel Bachmann is an emergency medicine physician and director of the hyperbaric medicine program at The Ohio State University Wexner Medical Center.