Carbon Monoxide in Vehicles
Carbon monoxide (CO) is a colorless, odorless gas in engine exhaust. It can build up inside a vehicle or a garage and kill people who never realize they’re being poisoned. Many deaths happen in winter, when cars are run in garages or tailpipes get packed with snow.
- All drivers
- Home & family
- Work vehicles
Photo: clearing snow away from a car’s tailpipe
How CO gets in
- Running a vehicle in a garage, even with the garage door open. CO can also seep into the house.
- Keyless ignition cars left running by mistake in an attached garage.
- Snow blocking the tailpipe while the car runs, such as when stuck in a snowbank or warming up in a driveway.
- Exhaust system leaks or rusted holes in the floor or trunk.
- Driving with the tailgate, trunk or rear window open, which can pull exhaust inside.
- Running generators, heaters or grills inside or next to a vehicle, camper or van.
Symptoms
- Headache, dizziness, weakness
- Nausea or vomiting
- Confusion, sleepiness, blurred vision
- Loss of consciousness
Symptoms are often mistaken for the flu or tiredness. Sleeping or drinking people can die before they notice anything.
If you suspect CO
- Turn off the engine and get everyone into fresh air immediately.
- Call 911.
- Don’t go back into the vehicle or garage until it’s cleared and the cause is fixed.
- Get medical care even if symptoms fade.
Prevention
- Never run a vehicle in a garage, even briefly. Pull it out first.
- Make sure keyless vehicles are fully off when you park.
- Clear snow from the tailpipe before starting, and keep it clear if you’re stranded. Run the engine only about 10 minutes an hour and crack a window. See Winter Driving.
- Have the exhaust system inspected if it’s loud, rusted or damaged.
- Install CO alarms in your home, especially near an attached garage. See Smoke & CO Alarms.
- Never use generators or fuel-burning heaters inside vans, campers or work trailers without proper venting and CO alarms.
Standards & references
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