Over the last few winters Edmontonians have been hearing carbon monoxide horror stories with saddening regularity and increasing frequency. Our area’s frosty winter weather means that furnaces run for extraordinarily long periods, and we all work hard to try and get that car warm before we have to climb in on weekday mornings. We’ve heard horrifying stories about homes where the owners simply left their fireplace chimney flue open, which then sucked in carbon monoxide expelled by the furnace’s chimney. But the risks of carbon monoxide are, in reality, pretty minor – as long as homeowners are aware of a few, simple carbon monoxide safety tips.
What is it?
In case you slept your way through high school chemistry class like I did, carbon monoxide is a colourless and odourless gas that is a by-product of fossil fuel combustion. Carbon monoxide (chemical symbol CO, if you want to impress your friends at a party) is constantly being dispelled in fairly large quantities from your furnace through its chimney, and through your car’s exhaust (and from volcanic eruptions and thunderstorms, in case you really want to be impressive at that party). It is harmless in small quantities, and only dangerous in higher concentrations. Part of the threat comes from the fact that you often can’t tell that the level is too high – until its too late. Early exposure to CO causes only flu-like symptoms like headaches, nausea, dizziness and burning eyes. In very severe cases, after prolonged exposure to dangerously high concentrations, CO poisoning can cause brain damage and death.
What causes it?
The most common cause of CO poisoning is running a vehicle in a garage where the door is not open. Though there doesn’t seem to be any rules guiding how far the garage door should be left open, its clearly safest to just leave it open all the way. Also common are problems with a blocked or cracked furnace chimney, or a leaking heat exchanger in a furnace. Since all gas and propane-burning appliances give off some CO, using such an appliance in an enclosed area like a home or vehicle is another common cause.
How do I protect myself?
Its pretty simple and easy – here’s a few tips:
- Have a qualified service technician inspect fuel-burning appliances, especially your furnace, once a year – and clean them if needed.
- Install at least one carbon monoxide detector, and replace the batteries regularly. When you’re purchasing the CO detector, be sure to get one that is CSA or ULC approved. Also be sure to follow all the manufacturer’s installation instructions to the letter, including where in the home they should be installed. Try to avoid putting them in unheated, humid areas, near vents or within two metres of heating and cooking appliances since that can cause sensor damage or false alarms.
- Check your vent pipes, exhaust fans and chimneys yearly – or get an inspector to do it. Cracks, corrosion or blockage (birds’ nests are a common one) may interrupt ventilation and cause carbon monoxide build up.
- Keep your fireplace flue closed when its not in use.
- Never run your car in the garage unless the garage door is wide open, and you give it some time to air out after you leave. New is the threat of remote starters – be very careful to keep remotes away from kids and pets if you keep your car in the garage, and consider disabling the starter when your car’s in the garage.
- Never use natural gas, propane or charcoal grills, space heaters, pressure-washers or outdoor fuel-burning apparatus inside your home or garage – or any other enclosed space (like a tent or vehicle).