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Flu or flue?

This article was published in November 2019 and may be outdated.

With the heating season upon us, the risk of carbon monoxide exposure increases.

Carbon monoxide (CO) exposure is caused by faulty or improperly vented heating equipment. Anything that burns propane, heating oil, kerosene, coal and wood can cause dangerous levels of CO in your home and workplace if not properly vented.

Furnaces, room heaters, fireplaces, hot water heaters, stoves or grills and any gas-powered vehicle or engine produce CO. Automobiles left running in garages, gas barbecues used inside the house, grills or kerosene heaters that are not properly vented, or dirty or plugged chimney flues or vents may also create unsafe levels of CO.

Carbon monoxide is an invisible, odourless, tasteless gas often referred to as “the silent killer.”

CO levels can build up even in warmer weather. Fifty-two people were evacuated from a Winnipeg hotel last July after Winnipeg Fire Paramedic Service emergency crews detected dangerous levels of CO inside the premises. More than 40 people were taken to hospital for treatment.

It’s believed CO had built up in the hotel because of inadequate ventilation related to gas-fired appliances, causing a negative air pressure. Instead of being safely vented, exhaust was being drawn back into the building.

Negative air pressure can also happen in your house during the winter heating season, particularly if you live in a newer home that’s well-insulated. In most instances, negative air pressure is caused by an inadequate amount of fresh air getting into the house. It can be addressed by installation of a proper fresh-air intake by a qualified contractor to supply air to your furnace.

Signs you may have negative air pressure in your home include: stale air; mould or mildew in bathrooms; smoking fireplaces; condensation on windows; or a water heater pilot light that keeps going out.

Family members complaining about not feeling well could also be a sign — and can’t be ignored.

Exposure to CO can mimic the common flu, but without a fever. Early exposure may cause nausea, headache, and drowsiness. Prolonged exposure can result in loss of consciousness, brain damage and death.

To keep CO out of your home or business, follow these tips:

  • Have your heating system inspected and maintained regularly by a licensed heating contractor.
  • If you have a wood-burning fireplace or stove; make sure it has a fresh-air intake duct.
  • Install a carbon monoxide alarm near sleeping areas, and on each level of your home. The alarm will not prevent CO, but will alert you to the presence of CO before dangerous levels are reached.
  • If you have a CO alarm, be familiar with its beep patterns, check the expiration date and follow the manufacturer’s instructions to regularly test the unit and replace the batteries. Most alarms will last up to 10 years.
  • If your CO alarm sounds, don’t ignore it. If you suspect equipment malfunction, turn off the fuel-burning appliance or equipment, open all windows and doors, go outside and call Manitoba Hydro for an inspection at 1-888-624-9376.
  • If anyone has symptoms of CO poisoning, open all windows and doors, evacuate everyone immediately, and call 911.

Learn more about carbon monoxide safety.