Carbon Monoxide Safety
If your CO alarm sounds OR you feel CO symptoms:
- Get everyone out of the building immediately — including pets
- From outside, call 911 for medical help if anyone feels unwell
- Call FortisBC emergency line: 1-800-663-9911 for gas-related emergencies
- Do not re-enter until first responders give the all-clear
- Call us at 604-359-1081 to inspect and repair the appliance once safe
Carbon monoxide is colourless, odourless, and tasteless. It's produced any time a fuel-burning appliance has incomplete combustion or venting issues. A properly installed and maintained boiler is very safe — but maintenance and CO alarms aren't optional.
What is carbon monoxide?
Carbon monoxide (CO) is a gas produced when fuel — natural gas, propane, oil, wood — burns without enough oxygen. It binds to hemoglobin in your blood 200x more readily than oxygen, depriving organs of oxygen even at low concentrations.
Healthy combustion produces almost no CO. Faulty combustion (dirty burner, low gas pressure, cracked heat exchanger, blocked venting) can produce dangerous levels in minutes.
CO exposure symptoms
Symptoms mimic the flu — many CO poisonings are misdiagnosed as illness, especially early in winter.
Mild exposure
Headache, dizziness, fatigue, nausea
Moderate exposure
Confusion, drowsiness, rapid heart rate, chest pain
Severe exposure
Loss of consciousness, seizures, death
How CO can be produced by a boiler
A properly running, maintained boiler produces near-zero CO. These are the failure modes:
Prevention
Install CO alarms correctly
BC Building Code requires a CO alarm within 5m of any sleeping area when a fuel-burning appliance is present. Place one on each floor with a sleeping area.
Replace CO alarms every 7-10 years
CO alarm sensors degrade. Most have a date stamped on the back — replace when expired.
Annual boiler maintenance
Combustion analysis catches CO production before it reaches dangerous levels in living areas.
Keep vent terminals clear
After snow, check that outdoor vent terminations aren't buried. Keep landscaping back 3 feet.
Don't modify mechanical room
Sealing off combustion air openings to "stop drafts" can cause backdrafting.
Address backdraft conditions
High-CFM range hoods, dryer vents, and bathroom fans can pull combustion gases back into the house. Make-up air may be required.
BC Building Code on CO Alarms
Since 2018, the BC Building Code (Section 9.32.3.9) requires CO alarms in any dwelling unit containing a fuel-burning appliance, an attached garage, or a shared wall with a fuel-burning appliance.
Placement:
- Within 5m (16 ft) of every bedroom door
- On every floor with a sleeping area
- Combination smoke + CO alarms acceptable if both functions are present
Alarms must meet CSA 6.19 or UL 2034. Hard-wired or 10-year sealed-battery alarms are recommended.
Book a combustion safety inspection
Calibrated CO and combustion analysis of your boiler, vent inspection, ambient air check, and a written report. $199 — peace of mind for your family.
Related safety pages
CO safety inspection · $199 · Peace of mind for your family
Call GasBoilers.ca — A CanroHeat Division — for expert installation, repair, replacement, maintenance, and emergency service.