A perspective on Carbon Monoxide

Carbon monoxide is a by-product of incomplete combustion and all oil and gas burning equipment has the potential to create carbon monoxide. Carbon monoxide is an odourless, tasteless invisible gas that is only slightly lighter than air so it will rise in a calm atmosphere. It is however easily mixed with any moving air which makes it move easily throughout a building. Because of its nature, this lighter than air gas can be found at floor level depending on air-flow.

Carbon monoxide is dangerous because it displaces the oxygen in the hemoglobin of our blood. Carbon monoxide molecules bond with hemoglobin 200 times more easily than oxygen. As more oxygen is unable to enter the blood stream, the effects of carbon monoxide begin.

Carbon monoxide is measured in parts per million, (ppm) in the atmosphere. This list shows common symptoms at increasing exposure levels.

200 ppm Slight headaches, tiredness, dizziness and nausea after 2-3 hours.

400 ppm Frontal headaches within 1-2 hrs, life threatening after 3 hours.

800 ppm Dizziness, nausea and convulsions within 45 minutes. Unconsciousness within 2 hours. Death within 2-3 hours.

1,600 ppm Headaches, dizziness and nausea within 20 minutes. Death within 1 hour.

3,200 ppm Headaches, dizziness and nausea within 5-10 minutes. Death within 30 minutes.

6,400 ppm Headaches, dizziness and nausea within 1-2 minutes. Death within 10-15 minutes.

To put this into perspective, walking across the intersection at Douglas and View will expose you to approximately 9ppm of carbon monoxide.

Carbon monoxide is also highly flammable. From the late 19th to the early 20th century the city of Victoria burned coal to produce “coal gas” which is carbon monoxide. In those days the gas in buildings was actually flammable carbon monoxide. Knowing the properties of carbon monoxide, no wonder people thought gas was so dangerous. We now have natural gas which is very safe.

In an apartment building the boiler room is separated from the rest of the building for fire protection. Also if something goes wrong you do not want flue gases and smoke entering the living areas. Boiler rooms receive fresh air from outside the building to provide enough combustion air for the boilers and water heaters. These fresh air supplies cannot be blocked. I have seen boiler rooms with combustion air blocked off because the room doubles as a work shop and feels cold in the winter. Restricting air to a boiler room can create incomplete combustion and carbon monoxide.

Carbon monoxide can be created by either restricting the amount of air or supplying too much air to the combustion process. Not enough air will create a dirty fire with soot and carbon monoxide. Too much air is called a lean fire and will create acrid odours and carbon monoxide. Both situations destroy the equipment efficiency and are potentially dangerous.

When we service combustion equipment, the carbon monoxide is tested for automatically within our digital flue gas analyzers. Modern combustion equipment cannot be set visually; they must be confirmed with an analyzer. All our analyzers show carbon monoxide in ppm and are calibrated annually by a third party.

It is not just boilers and water heaters that need attention. If you use a gas stove be sure to always use the exhaust hood. Carbon monoxide is created when heating up a pot full of cold water. The hotter the pot of water gets the less carbon monoxide is created. When the exhaust hood is used most gases are safely carried outside. Please make sure you have a carbon monoxide tester in your home if there is any fuel burning equipment. These detectors can be purchased at most hardware stores. Please check the batteries in the smoke detector at the same time.