Safety · checked 5 Oct 2026
The carbon monoxide alarm is going off
Safety, right now
- Get everyone outside into fresh air immediately. Don't delay for belongings.
- Call 911 from outside, even if everyone feels fine.
- Stay outside. Don't investigate, silence the alarm, or go back in.
Fix it now
- Get everyone outside immediately; take pets only if doing so won't delay escape.An alarming CO detector warns of a potentially deadly hazard.
- Call 911 outside. Count everyone; report symptoms and anyone missing.Emergency responders must check the home before you return.
- Stay outside until firefighters explicitly allow reentry, even if the alarm stops.Reentering can cause unconsciousness or death; never attempt an indoor rescue.
When to stop
Stop and get a heating and air technician if:
- Anyone has headache, dizziness, nausea, weakness, chest pain, or confusion: tell 911 immediately. From outside, also call Poison Control at 1-800-222-1222 for poisoning guidance; don't delay emergency help.
- Anyone is unconscious or not breathing: tell 911 immediately and follow dispatcher instructions. Never reenter to reach them.
- Responders identify a faulty appliance: keep it off until a qualified HVAC or appliance technician services it.
- The alarm sounds again after clearance: evacuate again, call 911 outside, and arrange qualified appliance inspection.
What it probably is
Malfunctioning fuel-burning furnace, water heater, or other applianceResponders detect CO; a qualified technician must identify the faulty appliance. Don't investigate yourself.For a pro
Blocked or improperly vented exhaustA professional finds a blocked flue or unsafe venting; homeowners cannot rule this out safely.For a pro
Generator, vehicle, grill, or other engine exhaust entering the homeFuel-burning equipment is operating indoors, in an attached garage, or near openings. Don't approach it.For a pro
Get it done
More than a quick fix? Vora gets quotes privately and recommends one heating and air technician.
Checked against
- CPSC: Carbon Monoxide Fact Sheet
- CDC: Carbon Monoxide Poisoning Basics
- CDC: What to Do to Protect Yourself During a Power Outage
- CDC: Avoid Carbon Monoxide Poisoning
Written for Vora from these public sources and checked on 5 Oct 2026. General guidance, not a substitute for a pro on site. In danger, leave and call 911.