Carbon monoxide is invisible, odourless, and potentially deadly within minutes in an enclosed space. Learn where it comes from, where to install alarms, what symptoms to watch for, and what to do if an alarm sounds.
Carbon monoxide (CO) is produced by anything that burns fuel. It has no reliable smell, colour, or taste, so your senses cannot warn you. In an enclosed space, dangerous concentrations can build quickly.
CO alarms are the only reliable household warning. Combine working alarms with maintained fuel-burning equipment, clear vents, and a plan that gets everyone outside immediately if an alarm sounds.
1. Remember That CO Is Invisible
Carbon monoxide is odourless and colourless. Do not wait for a smell or visible sign. A working CO alarm near sleeping areas and on each level of the building is essential protection.
2. Install CO Alarms
Install a carbon monoxide alarm near every sleeping area and on each level, following the manufacturer's instructions and local requirements. Test alarms regularly, replace batteries as directed, and replace the whole unit at the end of its service life.
3. Know the Symptoms
Headache, dizziness, nausea, weakness, and confusion can resemble the flu but may occur without a fever. If more than one person feels unwell at the same time, treat the situation seriously and move outside.
4. If a CO Alarm Sounds
Get everyone to fresh air immediately, then call 911. Do not go back inside to silence the alarm, find the source, or retrieve belongings. Wait for emergency responders to say it is safe, and seek medical attention if anyone has symptoms.
5. Know Common Sources
Common sources include furnaces, water heaters, fireplaces, stoves, generators, vehicles, and attached garages. Have fuel-burning equipment inspected and serviced by a qualified technician, and keep combustion-air and exhaust vents clear.
6. Never Run Fuel-Burning Equipment Indoors
Never run a vehicle, generator, barbecue, or other fuel-burning equipment in a garage, room, or other enclosed space. Opening a door or window is not a safe substitute for outdoor operation and proper clearance.
CO and Fire Protection Go Together
Smoke alarms, CO alarms, escape plans, and maintained extinguishers all support a safer home or workplace. InspectExtinguishers helps businesses and fire extinguisher service companies track equipment locations, inspections, deficiencies, and service history while they manage broader fire-safety responsibilities.
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