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Environmental and Workplace Health

Carbon Monoxide

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What is Carbon Monoxide?

Carbon monoxide (CO) is a gas that forms whenever you burn fuel like propane, natural gas, gasoline, oil, coal and wood. Because it is colourless, odourless and tasteless, carbon monoxide can't be detected without a carbon monoxide detector. Carbon monoxide can cause health problems before people even notice it is present.

What Are the Effects of Carbon Monoxide on Health?

When you inhale carbon monoxide, reduces your body's ability to carry oxygen in your blood.

The health effects can be very serious.

  • Exposure to low levels of CO may cause:
    • headaches
    • Fatigue
    • shortness of breath
    • flu-like symptoms
    • impaired motor functions (like difficulty walking or problems with balance)
  • At high levels, or if you are exposed to low levels for long periods of time, symptoms may include:
    • dizziness
    • chest pain
    • poor vision
    • difficulty thinking
  • At very high levels, CO exposure can cause:
    • convulsions
    • coma
    • death

What are the Sources of Carbon Monoxide?

Sources of CO include furnaces, gas water heaters/boilers, wood stoves, and other appliances that run on fuels.

If these devices are improperly installed or malfunction, they can release CO into your home.

  • Other sources of CO include:
    • exhaust fumes from vehicles or other gas-powered equipment, like lawnmowers, snow blowers, and power generators, used indoors or in your attached garage
    • chimneys that are blocked or dirty
    • fuel-burning cooking appliances, like gas stoves, propane, natural gas or charcoal grills
    • tobacco smoke

How Can You Reduce Your Exposure to Carbon Monoxide?

Take these steps to protect your family from exposure to CO in your home.

Put at least one carbon monoxide detector in your home to warn you if CO levels pose an immediate threat.

  • Put CO detectors in hallways outside bedrooms where you can hear them when you sleep.
  • Choose CO detectors that are certified by the Canadian Standards Association (CSA) or the Underwriters Laboratories of Canada (ULC).
  • Follow the manufacturer's directions for installing, testing and replacing detectors. Store the manual in a handy place. (If it is hard-wired to the house's electrical supply, ensure it has a battery-powered back-up).
  • If your CO alarm sounds, leave your home right away.
  • Call local authorities (9-1-1) and do not go back home until a professional has fixed the problem.
  • Keep in mind that CO detectors and smoke detectors have different purposes. You need both to stay safe.

CO detectors are designed to prevent immediate carbon monoxide poisoning. A carbon monoxide detector is not a substitute for proper installation and maintenance of fuel-burning appliances.

Maintenance is the key to keeping CO levels low

  • Make sure fuel-burning appliances, like furnaces, fireplaces and gas stoves, are well maintained and working properly.
  • Have a professional inspect appliances and clean chimneys at least once a year. Make sure your chimney is not blocked by snow or ice, bird nests or other debris.

Leave it outside

  • Never use a barbecue or fuel-burning camping equipment inside your home, garage, vehicle, camper or tent or close to a window.
  • Never use a power generator indoors or in an attached garage (even with the door open) or close to a window.
  • Don't use kerosene or oil space heaters or lamps in enclosed areas, unless they are specifically designed for indoor use and in a well-ventilated room.
  • Keep your home completely free of tobacco smoke.

No idling

  • Never let vehicles idle in the garage, even when the garage door is open.
  • Never run gas-powered lawnmowers, trimmers, snow blowers or other gas-powered equipment in the garage.
  • Keep the door between your house and the garage closed when not needed and seal leaks between the garage and the home.

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