Run a generator only outdoors, more than 20 feet from windows, doors and vents, and have a battery-powered or battery backup CO alarm. If an alarm sounds, leave the home immediately and call the fire department.
Why this matters
The CDC says more than 400 Americans die each year from unintentional CO poisoning not linked to fires, and more than 100,000 people visit an emergency department and more than 14,000 are hospitalized. Sleeping or intoxicated people can die from CO before they show any symptoms.
Where to put a generator
Never use a generator inside your home or garage, even with the doors and windows open. Run it only outdoors, more than 20 feet from windows, doors and vents. America's Poison Centers also say never to run a generator, gas-powered tool, charcoal grill or portable camping fuel device inside a home, garage, vehicle or tent.
Alarms
Use a battery-powered or battery backup CO detector in your home when using a generator. The CDC says to install detectors near every sleeping area, check the batteries when you change your clocks in spring and fall, and replace detectors following the manufacturer's instructions or every 5 years. America's Poison Centers suggest mounting alarms in the hallway near sleeping areas about five feet above the floor.
Symptoms
Common symptoms are headache, dizziness, weakness, upset stomach, vomiting, chest pain and confusion, and they are often described as flu-like. Poison Control says headache, nausea or flu-like symptoms that improve when you get outdoors, or several people in the same place developing symptoms together, can be a sign. Children and pets are often affected first.
If you suspect CO poisoning
If a CO alarm sounds, leave the home immediately and call your local fire department. If someone is unconscious, not breathing or having seizures, call 911 right away. Otherwise call Poison Control at 1-800-222-1222, which is free, confidential and open 24 hours a day.
Other sources of CO during an outage
Never burn charcoal indoors, use a portable gas camp stove indoors, or heat your house with a gas oven. Never run a car or truck in an attached garage, even with the garage door open.
Report generator poisonings
The CDC asks people to report any generator-related poisoning to the Consumer Product Safety Commission.
Opening a door or window does not make it safe to run a generator in a garage or house. Keep it outdoors and well away from openings.
Check your own location
See current official alerts and the impact for your ZIP code.
Sources
Reviewed by the Storm Incoming editorial team on October 26, 2026. Follow local emergency officials if their instructions differ.