What is Carbon Monoxide (CO)?

Carbon monoxide is a colorless and odorless gas that is a product of incomplete combustion.  When combustion is complete, carbon dioxide is produced.  Because we don’t assume that all combustion will be complete, codes require most combustion appliances to exhaust to the outdoors.  Combustion appliances and other sources of CO include the following:

• Boilers
• Hot water heaters (gas-fired)
• Furnaces
• Stoves and ovens
• Fireplaces
• Vehicle exhaust / attached garages
• Gas fired lawncare and cleaning equipment
• Portable generators
• Propane forklifts
• Unvented heaters
• Cigarette smoke

What are the health effects of CO?

When you breathe in air, the oxygen is transferred to your blood and picked up by the hemoglobin in your red blood cells. Your red blood cells then deliver the oxygen throughout your body where it is needed.  When you breathe in carbon monoxide, it can also be picked up by the hemoglobin.  In fact, your hemoglobin have an affinity for CO that is 200 times greater than oxygen!

When hemoglobin are saturated with carbon monoxide, your body is unable to deliver the oxygen needed.  Early symptoms may include headaches and fatigue.  At much higher concentrations, effects include confusion, loss of consciousness, and eventually death.

You mean my CO detector might not fully protect me?

We recommend installing CO detectors to alert you to deadly levels of CO.  However, not all carbon monoxide problems result in your detector alarming. Did you know that many people have low-level CO problems that never get discovered? UL rules prevent carbon monoxide detectors from alarming at levels below 70 ppm. However, the Environmental Protection Agency has identified a long-term exposure to 9 ppm as being harmful to health.

How do we test for carbon monoxide?

We set up a worst-case scenario by operating exhaust fans and other devices that depressurize the home or building. When your home or building gets temporarily depressurized, combustion gases can get pulled indoors down through the flue rather than being exhausted outdoors. Because your space may only be depressurized for short periods of time, it may be difficult to schedule our inspection to measure at the exact right time.  Therefore, we operate exhaust fans to create the worst-case scenario of negative pressure when performing detailed measurements of carbon monoxide.

Once we have established a worst case scenario, we’ll test each combustion appliance separately and in combination with others.

We also test carbon monoxide by logging concentrations over a day or two and looking at the trends in the resulting charts.  We may find a spike in CO that is related to a specific activity or piece of equipment.