The CO alarm is going off. Believe it.
Carbon monoxide has no smell, no color, no taste. The alarm is the only sense you have for it — treat it as fact.
Do this now
- Get everyone outside to fresh air. Count heads, pets included.
- Call 911 from outside. Tell them it's a CO alarm.
- If anyone is dizzy, confused, nauseated, or sleepy, say so — that's CO poisoning until proven otherwise.
- Stay out until responders clear the house and find the source.
Where CO comes from
Anything that burns fuel indoors, badly vented: furnace, water heater, gas stove, fireplace, a car idling in an attached garage — and after storms, the classic killer, a generator running in a garage or too close to the house. CO deaths spike in the exact weeks power outages do.
The symptoms lie to you
Low-grade CO poisoning feels like the flu without the fever: headache, fatigue, nausea. The dangerous part is that it makes people sleepy and confused — the two things that stop them from leaving. If the alarm sounds at night, do not sit on the edge of the bed deciding whether you feel fine. Walk everyone out first and feel fine outside.
After the all-clear
Find and fix the source before anyone sleeps in the house again — a technician for the furnace or water heater, not hope. Replace CO alarms per their date stamp (most last 5–10 years), put one on every sleeping level, and never silence a chirping one without replacing the battery that day.
Do not
- Don't open windows and wait it out inside — leave first.
- Don't assume it's a false alarm because you can't smell anything. You can never smell CO.
- Don't run a generator in the garage, even with the door open — 20+ feet from the house, outdoors.
- Don't re-enter until the fire department clears it.
Common questions
My CO alarm went off but I feel fine — is it real?
Treat it as real. CO is undetectable by your senses, and early poisoning feels like ordinary tiredness. Go outside, call 911, and let a meter make the call.
What are carbon monoxide poisoning symptoms?
Headache, dizziness, weakness, nausea, confusion, and sleepiness — flu-like, but without a fever, and often affecting the whole household at once.
Where should CO alarms be installed?
On every level of the home and outside each sleeping area — and replace units by their expiration date, typically 5–10 years.
Sources — official guidance
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