As winter approaches, the Maine Center for Disease Control and Prevention is reminding people of some simple steps they can take to prevent carbon monoxide poisoning. Since Nov. 1, 13 people have been poisoned in Maine by carbon monoxide gas because of improper use of gas-powered generators, faulty heating systems and working on running engines in a closed garage. In Maine, 68 percent of carbon monoxide poisonings happen between November and March.

Anything that burns fuel, such as an oil or propane boiler or wood stove, produces carbon monoxide gas. Carbon monoxide cannot be seen, smelled or tasted, and can quickly build up inside a home without anyone noticing. Improper placement and use of gas-powered generators during power outages is a significant concern, especially during the winter. One generator can produce as much carbon monoxide as 100 idling cars.

Anyone with a portable generator should have an extension cord long enough that the generator can run outside, at least 15 feet from windows and doors. Be prepared to keep the generator protected from rain, ice and snow.

Though it may also be tempting during the cold months to work on engines in garages while the motor is running, this can also be very dangerous. About one in five carbon monoxide poisonings each year occur in garages, sheds or barns while people conduct engine repair or maintenance. Even with windows or doors left open, carbon monoxide can build up inside to dangerous levels.

Warning signs of carbon monoxide poisoning are flu-like symptoms, such as headache, nausea, vomiting, dizziness, drowsiness, and confusion, but no fever. Carbon monoxide poisoning can cause loss of consciousness and death. People who are sleeping or intoxicated can die from carbon monoxide poisoning before ever experiencing symptoms.

While the best way to prevent carbon monoxide poisoning is to not let carbon monoxide gas build up in your home, having carbon monoxide detectors with a battery backup near every sleeping area can save lives and is especially important when heating your home. As of 2016, an estimated seven out of every 10 households in Maine had a carbon monoxide detector, nearly double the number in 2004.

Regularly check that all detectors have fresh batteries and are functioning properly. If the alarm on your detector goes off, assume it is because of carbon monoxide and not a dead battery and leave the house immediately. Call the fire department or 911 and do not go back into your home until the fire department tells you it is safe.

In addition, people who are exposed to carbon monoxide poisoning should get medical attention. Call the poison center at 800-222-1222 or your doctor after leaving the house.