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Fit CO alarms and smoke alarms, and monitor CO2

Carbon monoxide is colourless and odourless and can kill sleeping people before they notice symptoms. Every home with a combustion appliance, generator or attached workshop needs CO alarms.

How

1. Install battery or battery-backup CO alarms near every sleeping area, as the CDC recommends.
2. Test batteries twice a year and replace alarms per the manufacturer or about every 5 years.
3. Run generators only outdoors, more than 20 ft (6 m) from windows, doors and vents.
4. Never burn charcoal or use camp stoves indoors.
5. Add a CO2 monitor in bedrooms as a check that ventilation is working. Health Canada sets a long-term indoor exposure limit of 1,000 ppm as a 24-hour average; readings that climb above that overnight mean more fresh air is needed.
6. Fit smoke alarms to your local code and coordinate with the safety module's fire plan.

Safety: CO symptoms (headache, dizziness, nausea, confusion) are often mistaken for flu. If an alarm sounds, get everyone outside into fresh air and call emergency services.

Sources

1. Carbon Monoxide Poisoning Basics. U.S. Centers for Disease Control and Prevention, accessed 2026-11
2. Carbon dioxide in your home. Health Canada, accessed 2026-11

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