Sally thought she was just getting the flu and figured both of her daughters were too, since they seemed tired and the 3-year-old had difficulty getting up after losing her balance while playing in the living room. But Sally grew worried when one of the girls fell asleep at the kitchen table and she herself started to vomit and became increasingly disoriented.
Just before losing consciousness, Sally phoned her husband at his office, and he called for medical help. Fortunately, help arrived in time, and the cause of the problem was identified. Improper venting of the gas furnace and clothes dryer had caused a buildup of carbon monoxide. When inhaled, the poisonous gas gets into the blood and significantly reduces the oxygen supply.
Each year, close to 100 Canadians die of accidental carbon monoxide poisoning, and many more require medical attention as a result of exposure to toxic levels. Most households have at least one potential source of carbon monoxide, which is difficult to detect because it’s odorless and colorless. Health Canada biologist Marc Bourgeau says that, in some cases, it can remain at low levels and go undetected for days or weeks, with poisoning symptoms mistaken for the flu or food poisoning. But, in other cases, it can reach potentially lethal levels in a matter of hours.
Any appliance or heating device that uses a combustible fuel, such as gas, oil, wood, kerosene or charcoal, can produce carbon monoxide if it is improperly installed or vented or poorly maintained, or if it breaks down. To guard against the silent killer, George Smith of the Canada Safety Council recommends taking the following precautions:
* Chimneys, flues, oil and gas furnaces and gas water heaters should have annual professional inspections for cracks, corrosion and leaks. External vents – essential for gas appliances – and chimneys should also be checked for blockages, such as loose insulation, leaves or birds’ nests.
* If you have a wood-burning stove, have the stovepipe professionally cleaned at least twice a year to ensure proper ventilation. To avoid incomplete combustion, burn only dry seasoned wood.
* Watch for signs of carbon monoxide buildup in your home: stale, smelly stuffy air, excessive soot around a fireplace, furnace or chimney; excessive smoke from a wood-burning fireplace or stove; no draft in the chimney of a wood-burning fireplace.
* If you have a gas range or cooking top, an exhaust fan is a must. But avoid running kitchen or bathroom exhaust fans for long periods of time because they can remove too much air from your home and rob a furnace or gas water heater of adequate air for complete combustion. Confining gas-fired equipment in a tight space – e.g., partitioning it off from the rest of the room – can also impede the air supply.
* Never leave a car idling more than a minute or two in a garage attached to a home or in the underground of an apartment building. Carbon monoxide can seep into the dwelling. Warm up your car outside instead.
* Never barbecue in an enclosed space, such as a garage, even if the door is open.
* Cottagers who use portable kerosene heaters should partially open a window to ensure adequate ventilation. Never leave a heater unattended; if the flame goes out and the heater is left on, carbon monoxide can be released.
* Install a carbon monoxide detector that sounds an alarm; about $35 to $70 at many hardware stores.
At low levels
Persistent headaches. Feeling ill at home but better after you leave.
At high levels
Dizziness. Confusion. Vomiting. Drowsiness. Blurry vision. Loss of muscle control. Rapid heartbeat and pulse. Tightness in the chest.
At extremely high levels
Fainting. Coma. Can lead to brain damage or death.
If you suspect that there’s carbon monoxide in your home, leave at once; call the gas company or fire department.