CO alarms
A CO alarm near the bedrooms is the last line of defence when outages bring generators, fuel heaters and the risk of carbon monoxide.
Used for: Emergency kit
Our picks
Detects
Carbon monoxide only
Smoke and carbon monoxide
Power Tie
Plug-in with a 9 V backup
Sealed 10-year battery
Mounting
Needs a socket; sits low on the wall
Wall or ceiling, no socket needed
Battery
Replaceable 9 V
Sealed: whole alarm goes at 10 years
Warranty
7 years
10 years
Canada Tie
US model, no CSA 6.19 stated
US model, no CSA 6.19 stated
Choose the First Alert CO3-P01 Plug-In Carbon Monoxide Alarm with Battery Backup if you want a CO alarm you can plug in anywhere, with a battery you can replace
Choose the First Alert SMCO210 10-Year Battery Smoke and CO Alarm if you want one sealed alarm for smoke and CO that ignores outages
Before you buy
- Check the listing US alarms should list UL 2034; in Canada look for a Canadian certification mark such as CSA on the alarm and the box.
- Place near sleeping areas Fit one outside sleeping areas and on every level, as CPSC and Health Canada advise.
- Replace on time CO sensors wear out. Note the end-of-life date and replace the alarm when it warns you.
Guides
Best-of
The best generators for a power outage in Canada
Five portable generators with CO shut-off for winter outages, ranked for Canadian homes: size, safe hookup, fuel and the Canadian mark.
Comparison
Portable power station vs generator for a power outage
Silent and indoor-safe, or energy for days: how a 1 kWh power station and a 4,500 W dual fuel inverter compare through a real outage.
CO alarm questions
Where should I put a CO alarm?
Health Canada says the most important place is the hallway outside sleeping areas. The US CPSC advises battery or battery-backup alarms on every level and outside sleeping areas, interconnected where possible, and tested monthly.
What should a Canadian buyer look for?
An alarm certified for use in Canada. Health Canada says the certification mark, such as CSA, must be on both the alarm and the packaging. Both alarms we list are US models listed to UL 2034; neither states a Canadian (CSA 6.19) listing, so we mark them US only.
What do I do if the CO alarm sounds?
Get everyone out at once, call 9-1-1 from outside and don’t go back in until responders say it is safe, says Health Canada. Never run a generator, barbecue or camp stove indoors or in the garage. Our generator roundup covers safe placement.