Carbon monoxide and the car, in the garage and in the snow

Car exhaust contains carbon monoxide, a gas you can't see or smell. It builds up fast in an enclosed space, and it can also leak into the car through a damaged exhaust system. These checks keep it out of the air you and your passengers breathe.

In the garage

• Never run the engine in an attached garageThis applies even with the garage door open.
• Open a detached garage door firstOpen it before you start the engine, every time.
• Put a carbon monoxide detector near every sleeping areaUse battery-operated or battery backup detectors. Check the batteries each spring and fall when you change the clocks. A detector in the house warns you if fumes from the garage get inside.
• Never run a generator in the garageThis holds even with the garage doors and windows open. Run a generator outdoors, more than 20 feet from any window, door or vent.

The car itself

• Have the exhaust system checked once a yearA small leak in the exhaust can let carbon monoxide build up inside the car while you drive. Ask for the check at a regular service visit.
• Open the vents or windows when the tailgate is upDriving with only the tailgate or trunk open pulls exhaust into the car.

Stuck in the snow

• Stay in the carIn blowing snow and cold, it's easy to lose your way if you leave the car on foot.
• Clear snow from the tailpipeA blocked tailpipe sends exhaust back into the car. Check it before you run the engine, and again each time you start it.
• Run the engine about ten minutes each hourOpen a window slightly for fresh air while it runs.
• Make the car easy to findAt night, turn on the dome light while the engine runs. Tie a bright cloth to the antenna or a door.

The symptoms

• Know what poisoning feels likeThe most common symptoms are headache, dizziness, weakness, upset stomach, vomiting, chest pain and confusion. They're often mistaken for the flu. Breathing in a lot of carbon monoxide can make you pass out, or kill you. Infants, older adults and people with heart disease, anemia or breathing problems get sick from it more easily.
• Get fresh air at the first signIf anyone in the car feels this way, turn the engine off, get everyone into fresh air and get medical help.
• Know that some people won't feel itA person who is asleep or has been drinking can die from carbon monoxide poisoning before having any symptoms.

Before the next storm

Keep a snow brush in the car, since it clears the tailpipe as well as the windows. A winter car kit lists the rest of what to carry.