Carbon Monoxide: Silent But DeadlyHome Safety

Problem: Carbon monoxide is a colourless, odourless gas. And it's toxic. Even the smallest amount of exposure can cause serious health problems, especially for the most vulnerable, including children and the elderly. What makes it all the more dangerous is, because we can't see it, smell it or taste it, it can be in our homes without us knowing. Thankfully, though, once you know how carbon monoxide gets into the house and how to safeguard against it, you can protect your home and your family.

Where does carbon monoxide come from?
Carbon monoxide (CO) is a gas that forms when fuel-propane, natural gas, gasoline, oil, coal or wood-is burned. And, any appliance or device that burns these types of fuel can produce it, from furnaces and fireplaces, gas stoves and barbecues to cars. Inside your home, fuel-burning equipment that is properly installed and maintained produces little CO, which is safely vented outside. However, if not properly installed or maintained, the gas can leak into the house (and quickly rise to dangerous levels).

When carbon monoxide levels rise in your home, even though you can't see it or smell it, there are warning signs. Carbon monoxide reduces the amount of oxygen in your blood. Signs of exposure range from headache (this is the most common and earliest symptom), shortness of breath, tiredness and other flu-like symptoms. Indications of more serious levels of gas include nausea, dizziness, chest pain and disorientation (these symptoms can also occur if a person has been exposed to low levels of CO for long periods of time). At very high levels, this gas can cause convulsions, unconsciousness, coma, brain damage or death.

What can be done to prevent carbon monoxide?

Solution: The best defence is to ensure carbon monoxide has no way of getting inside the house. This involves proper maintenance and a few helpful pointers.

• To begin with, it's important to have your furnace checked annually by a professional to ensure it's in good working order.
• Chimneys and vents should be inspected each year for cracks, blockages or damage, and fireplaces need to be examined for blocked or closed flues.
• Periodically, you can also check outside to make sure exhaust vents for the dryer, furnace, wood-burning or gas stove are clear of debris, including lint, leaves or snow. (Also, the flue and fresh air intake in wood-burning fireplaces should always be open when it's in use.)
• The garage is another source of concern, whether it's attached to the house or not. Never let a car idle in the garage, even if the door is open. In fact, it's best never to run any gas-powered equipment - whether a snow blower, lawn mower or tool - there.

How can I be sure my home and family are safe?

Solution: Once you've done your best to ensure your home is protected from possible carbon monoxide leaks, the next step is to install CO detectors. It's smart, and in some cities, it's the law.

There are three basic types of CO detectors:

1. Metal-oxide-semi-conductor (MOS) carbon monoxide detectors: These are connected to your home's power supply and use heated tin oxide which reacts with the gas to determine levels of exposure.
2. Biomimetic carbon monoxide detectors: These are often battery-operated and work with gel-coated discs that darken in the presence of CO to sound an alarm.
3. Electrochemical carbon monoxide detectors: These are available as plug-in or battery-operated models. A chemical reaction with the gas creates an electrical current that sets off an alarm.

Any type of CO detector is a good choice. What sets them apart is price and convenience. Hardwired CO detectors that tie into your home's power supply require professional installation. Plug-in or battery-operated models are less expensive and easily installed by a homeowner. In either case, you may want to consider a detector that also offers a memory that continually monitors CO levels, which can be reviewed at the press of a button.

Whichever type you choose, check that the product is certified by the Canadian Standards Association (CSA), and buy at least one (the first of which should be installed in the hallway near your family's bedrooms). If it's battery-operated, be sure to replace the batteries regularly. In fact, to be on the safe side, be sure to replace your carbon monoxide detectors at least every five years (some manufacturers say seven). Also: most detectors have a test button that should be pressed once a week to ensure the device is working.