The Silent Killer

Carbon Monoxide

Continued exposure or high concentrations may cause severe headaches, brain damage, breathing difficulties, cardiac problems and even death.

What is Carbon Monoxide?

CO is a colourless, odourless, tasteless gas. It is a by-product of incomplete combustion (unburnt fuel such as gas, oil, wood, etc.)

Why is it Dangerous?

If there is CO in the air you breath, it will enter your blood system the same way oxygen does, through your lungs. The CO displaces the oxygen in your blood, depriving your body of oxygen. Low concentrations of CO can go undetected and can contribute to ongoing, unidentified illnesses. At high concentrations, it can be deadly.

What are the Symptoms?

Long term exposure to low concentrations may cause slight headaches, nausea, dizziness, confusion, fatigue and shortness of breath with only moderate exertion. Continued exposure or high concentrations may also cause severe headaches, brain damage, breathing difficulties, cardiac problems and even death.

Senior citizens, people with respiratory or coronary problems, pregnant women, unborn babies, infants and young children exposed even to low levels of CO for long time periods may have similar health affects as those exposed to high concentrations of CO.

Why is it Called the “Great Imitator”?

Symptoms of CO poisoning are very similar to the flu. Illness in your pets preceding illness in a family member may suggest CO poisoning.

What Can Produce CO in our Homes?

Anything that burns fuel or generates combustion gasses including gas stoves, fireplaces, barbecues, automobiles, ranges, space heaters, furnaces, boilers and water heaters.

Solid fuels, such as wood, always produce carbon monoxide when they are burned. Gas and liquid fuels may produce little or no CO.

What are the Most Common Sources of Carbon Monoxide?

Automobile exhaust in attached garages
This is responsible for 60% of all CO alarms. People who warm their cars up in the garage are trapping CO inside the garage; this can lead to CO finding its way into the home.

Gas cooking appliances
Reported to account for 20% of CO alarms. This may be a result of a misused, poorly maintained, poorly installed, or unvented cooking appliance.

Poor draft/venting for fuel burning appliances
This is one of the most common and serious causes for CO build up and has been reported to account for up to 19% of CO alarms. The products of combustion are not being safely expelled to the exterior. This could be due to venting problems, such as blocked chimney flues or inadequate venting for appliances or fireplaces. Other problems include poor installation and negative air pressure in the house; this can cause back drafting, often due to exhaust fans.

It is an imperative that we do not deprive our heating equipment and fuel burning appliances of air. Combustion air is essential for safe operation of furnaces, water heaters, and other fuel burning equipment.

Due to more energy-efficient, airtight homes, and less natural ventilation there are more problems with carbon monoxide today than 30 years ago.

How can I guard against carbon monoxide poisoning?

The first line of defence is to have your home heating systems, fuel burning appliances, flues and chimneys checked and/or cleaned annually.

The second line of defence is a CO detector.

CO detectors are designed to warn homeowners when CO reaches dangerous levels within the home. They sample the air at specific time intervals using a microchip inside the detector, which stores readings and keeps track of CO levels over time

CO detectors are designed to protect the average healthy human from death or serious injury under the current standards. However, people who are more susceptible cannot depend on these devices for total protection. In this case, more sensitive CO detecting equipment should be used.

Where to install a CO detector?

Install one or more CO detectors in accordance with the manufacturer’s recommendations; usually one per floor. Maintain and test regularly as instructed by the manufacturer.

How does all of this relate to your home inspection?

A home inspection may reveal a potential Carbon Monoxide source. Common deficiencies found during inspections include:

• Venting deficiencies

• Damaged or rusted flue pipes

• Dirty or blocked chimney flues

• Cracked heat exchangers

• Gas proofing deficiencies

• Inadequate combustion air

• Poorly installed equipment