As temperatures drop and folks settle indoors during the cold weather months, there’s naturally an increased use of furnaces and fireplaces. Even though these fuel-burning appliances are required to be safely designed, if they are not properly installed, inspected and maintained regularly, CO poisoning has the potential to pose a real danger in any home.
Keeping yourself and your loved ones safe from potential CO poisoning starts with two critical steps: annual inspections of all fuel-burning appliances in your home and having certified, working CO alarms in your home.
Yes, You Need Both!
While CO presents serious hazards, the Technical Standards and Safety Authority (TSSA) reminds you that doubling down on these defences can significantly reduce CO risks and any potential harm.
Annual inspections of all fuel-burning appliances:
Have all fuel burning appliances in homes inspected and maintained every year through the services of a TSSA-registered contractor who must employ certified technicians - the only businesses that are legally authorized to do fuel-related work in Ontario.
Visit TSSA’s-registered fuels contractor search tool to find or verify companies with a valid TSSA Registration
CO alarms*:
Have working, certified, carbon monoxide or smoke/carbon monoxide alarms* installed in your home. Make sure you test the alarms, replace batteries regularly and replace the alarms when they expire, typically every 7-10 years or according to the manufacturer’s instructions.
*Starting January 1, 2026, new CO alarm rules come into effect for existing homes — including detached and semi-detached houses, townhomes, and cottages – that will require CO alarms adjacent to each sleeping area (near all bedrooms) and on every storey of your home, even storeys without bedrooms, if your home has any of the following: a fuel-burning appliance (like a furnace, water heater or stove that uses natural gas, propane, oil, or wood), a fireplace, an attached garage, or air that comes from a fuel-burning appliance not contained within the home (e.g., an appliance in a utility shed).
For more info about the CO alarm requirements, contact your local fire department or visit Ontario.ca/CarbonMonoxide,
To learn more about CO visit COsafety.ca and check out some of the TSSA’s latest resources, including this CO Checklist video, the You Need Both info card, and CO backgrounder.
About Technical Standards and Safety Authority:
For TSSA, safety is a shared responsibility. At TSSA, we believe safety results from collaboration across the entire system—from equipment designers and manufacturers to installers, maintainers, owners, insurers, consumers, government, and the public. When everyone works together, we achieve better safety outcomes. That’s why partnership can help make Ontario a safer place.