Carbon Monoxide Safety & Upcoming Ontario Fire Code Changes Carbon monoxide (CO) is often called the silent killer — and for good reason. It is colourless, odourless, and impossible to detect without an alarm. Even low-level exposure can cause headaches, dizziness, and confusion, while higher levels can be fatal within minutes. Most CO incidents are linked to fuel-burning appliances, fireplaces, or vehicles running in attached garages, making early detection critical. Effective January 1, 2026, updates to Ontario’s Fire Code will come into force to strengthen carbon monoxide protection in homes and residential buildings across the province. These changes are intended to improve early warning, reduce risk, and ultimately save lives. What’s Changing in 2026 Ontario Regulation 87/25 amends the Ontario Fire Code (O. Reg. 213/07) to expand carbon monoxide alarm requirements. The goal is to ensure CO detection in any building where a fuel-burning appliance or attached garage may pose a risk. Key Updates to the Ontario Fire Code More alarms required in homes If you live in a detached home, semi-detached home, townhouse, cottage, or similar dwelling with any of the following: a fuel-burning appliance, a fireplace, an attached garage, or ducted heat from a fuel-fired appliance located elsewhere, you must continue to have a carbon monoxide alarm installed near every sleeping area. New for 2026, an alarm will also be required on every storey of the home, including basements and floors without bedrooms. Expanded coverage in multi-unit residential buildings Apartments, condominiums, hotels, motels, boarding houses, and retirement homes will see expanded requirements. Carbon monoxide alarms will be required in: suites adjacent to service rooms containing fuel-burning appliances, suites adjacent to parking garages, service rooms themselves, and in some cases, public corridors heated by fuel-burning systems. Special rules for care and treatment occupancies Group homes, care facilities, and retirement homes will be subject to stricter installation requirements to protect residents who may require assistance evacuating in an emergency. Enforcement and responsibility Carbon monoxide alarms may be hardwired, battery-operated, or plug-in. Combination smoke/CO alarms are permitted if properly certified. Hardwired or plug-in alarms must include a battery backup to ensure operation during power outages. Property owners — including landlords and condominium boards — are responsible for installation and ongoing maintenance. Tenants must not remove or disable alarms and must report any issues. Failure to comply may result in fines ranging from ticketable offences to more significant penalties for repeated violations. Quick Safety Tips to Prepare Before 2026 Whether you’re a homeowner, landlord, or property manager, preparing early is strongly encouraged. 1. Identify fuel-burning sources Take inventory of anything that burns fuel, including furnaces, water heaters, fireplaces, woodstoves, generators, and attached garages. Have all fuel-burning appliances and venting systems inspected and maintained regularly by qualified technicians. This will help determine where alarms must be installed under the updated Fire Code. 2. Install alarms on every storey now Installing alarms well before the January 1, 2026 deadline allows time to confirm proper placement, budget for upgrades, and ensure consistent protection throughout the building. 3. Keep up with maintenance Test carbon monoxide alarms monthly and replace batteries at least annually, or sooner if the unit fails a test. Replace alarms according to manufacturer recommendations.Landlords and property managers should incorporate testing into routine maintenance schedules and keep records. Alarms must be tested when a tenancy changes or when electrical system modifications occur, and tenants must be provided with maintenance instructions. 4. Maintain proper ventilation Never operate unvented fuel-burning equipment indoors. Do not idle vehicles in garages — even with the door open. Carbon monoxide can accumulate quickly and seep into living spaces through doors, cracks, and shared ventilation systems.