CARBON MONOXIDE - Q & A

What is carbon monoxide and why should I be concerned?

Carbon monoxide is a dangerous poisonous gas. It is often referred to as the Silent Killer, because it has no odour or taste and cannot be seen. The presence of carbon monoxide inhibits the blood's capacity to transport oxygen throughout the body, which can eventually lead to brain damage. In any enclosed space even a small accumulation of carbon monoxide can be dangerous.

What are the potential sources of carbon monoxide?

Although many products of combustion can cause discomfort and adverse health effects, it is carbon monoxide (CO) that presents the greatest threat to life. CO is produced by incomplete combustion of fuels such as natural gas, propane, heating oil, kerosene, coal, charcoal, gasoline or wood. The incomplete combustion of fuel can occur in any device that depends on burning for energy or heat such as furnaces, boilers, room heaters, hot water heaters, stoves or grills and in any gasoline powered vehicle or engine. Tobacco smoke also adds CO to the air you breathe.

When properly installed and maintained, Your natural gas furnace and hot water heater do not pollute your air space with carbon monoxide. Natural gas is known as a "clean burning" fuel because under correct operating conditions the combustion products are water vapour and carbon dioxide, which are not toxic. Carbon dioxide is present in the air we exhale and is necessary for plant life. The products of combustion are vented from furnaces, fireplaces and water heaters to the outside by means of a duct or chimney.

For correct operation of fuel burning equipment there must be:

• An adequate supply of air for combustion
• Proper venting of the products of combustion through the chimney, duct or vent to the outside

Typical Carbon Monoxide Problems:

1. Equipment problems, due to defects, poor maintenance, damaged and cracked heat exchangers
2. Collapsed or blocked chimneys or flues, dislodged, disconnected, or damaged vents
3. Downdraft in chimneys or flues caused by improper flue runs, poor location of flue exhaust or wind conditions
4. Improper installation or operation of equipment, chimneys or vents
5. Air tightness of house envelope results in a lack of air for the combustion process for units using chimneys
6. Exhaust ventilation/fireplace competing for air supply

What are the potential sources of carbon monoxide in my home/office?

1. Clogged chimney
2. Wood stove
3. Wood or gas fireplace
4. Automobile and garage
5. Gas water heater
6. Gas or kerosene heater
7. Gas or oil furnace
8. Gas appliances like stove or dryer
9. Cigarette smoke

What are the possible symptoms of carbon monoxide poisoning?

Carbon monoxide is colourless, odourless, tasteless and very toxic. When inhaled, it produces an effect known as chemical asphyxiation. Injury is due to the combining of CO with the available hemoglobin in the blood which lowers the oxygen-carrying capacity of the blood. In the presence of carbon monoxide, the body is quickly affected by oxygen starvation.

The following symptoms are related to carbon monoxide poisoning and should be discussed with all members of the household so that you know what to look for:

• Extreme exposure (400 PPM for 4 hours) - unconsciousness, convulsions, cardio-respiratory failure, vomiting, fast heart rate, coma
• Medium exposure (400 PPM for 2 hours) - severe throbbing headache, drowsiness, confusion, vomiting, fast heart rate
• Mild exposure (400 PPM for 1 hour) - slight headache, nausea, fatique

Many people confuse these symptoms with those of the flu or the start of a cold. Young children and household pets may be the first to be affected. Exposure during sleep is particularly dangerous because the victim usually does not awaken.

For most people, mild symptoms generally will be felt after approximately 4 hours of exposure to 100 ppm of carbon monoxide. Higher levels and exposure times will lead to more severe symptoms or death.

What should I do?

Prevention is your best protection.

• Have your furnace, gas fireplace and any other fuel burning appliances inspected annually by a qualified technician.
• Have your chimney and flue cleaned professionally.
• Make sure burner flames on furnaces and cook stoves are blue, not yellow-orange.
• Never run an automobile or gasoline engine in an enclosed space.
• Install a carbon monoxide detector in or near each sleeping area in your home.

Where should I install my CO detector?

Because carbon monoxide moves freely in the air, it doesn't need to be mounted near the ceiling. Unlike smoke alarms, CO detectors can be placed at any height in your home from floor to ceiling. As the human body is most vulnerable to the effects of carbon monoxide during sleeping hours, the suggested location is outside primary sleeping areas on each level of your home. The electronic sensor detects carbon monoxide, measures the concentration and sounds a loud alarm before a potentially harmful level is reached.

Do not place the detector:

• Where the temperature may drop below 4.4°C or exceed 37.8°C
• Near paint thinner fumes or household cleaning supplies
• Within 1.5 metres of open flame appliances such as stoves, fireplaces and furnaces
• In exhaust streams from gas engines, automobiles, vents, flues or chimneys.

How does carbon monoxide escape from my sealed gas fireplace?

There are 2 main areas where CO can escape:

• From around the glass on the fireplace
• From the holes through which small pipes and wires enter the fire box from the lower compartment

These areas must be inspected yearly for faulty or cracked gaskets and seals. If the gasket on the glass is cracked, you may get uncharacteristic black or smokey deposits on the glass or carbon on the upper exterior of the fireplace. If your vent is blocked, the unit may spill CO but more than likely the fire will go out from lack of oxygen or the high temperature limit present on most units will shut it down. Again the vent should be checked yearly. Because gas fireplaces run intermittently for short time periods and not usually when you are sleeping, low levels of carbon monoxide poisoning may go undetected for years if not inspected.

Where do I get a good CO detector?

Carbon monoxide detectors are available at most hardware and lumber outlets. I sell a low cost, high quality CO detector made by American Sensors. Call or E-mail me if you are interested in more information about this product.

Is my family at risk?

Take this Healthy Home Quiz to see how your home stands - health and safety -wise.

1. Do you keep a list of emergency phone numbers near the telephone?
2. Do you have your heating system inspected annually?
3. Do you schedule regular maintenance for gas appliances (water heater, gas fireplace, furnace)?
4. Do you have your chimney and flue cleaned professionally?
5. If you have an attached garage, is it ventilated properly?
6. Do you have a carbon monoxide detector in your home outside every sleeping area?

If you answered yes to all the questions, this means you take home safety seriously. If you answered no to any question, you and your family are at risk.

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