As part of the home inspection I check the amount of Carbon dioxide in the home. The main reason for this test is to assess the air exchange in the home be it passive or mechanical.
The long-term exposure limit is 1000 parts per million (ppm) based on a 24-hour average. These levels may rise temporally to higher levels based on occupant levels and other activities. The main concern is long term levels.
Learn about sources of CO2, and health effects of higher levels and how to lower exposure to CO2 in your home by visiting Health Canada
Particulate and VOCs testing:
I also check the amount of particulates in the air as well as VOCs. The amount of particulate in the air will vary depending on many factors such as occupant activity such as cooking, showering, the use of cleaning products and chemicals along with smoking tobacco or marijuana. Because we do not know what activity took place in the home before arriving for the home inspection the test results need to be considered with the above in mind. If the test shows low levels in spite of what was going on in the home before the home inspection, then this is good news!
What if the levels are high? If the levels of particulate and/or VOCs are high along with high carbon dioxide levels, this would mean you need increased ventilation in the home. Increased ventilation will lower all 3, particulate, VOCs and carbon dioxide.
What if the levels are high but the carbon dioxide levels are low? At this point the first step is to identify the source of particulate and/or VOCs. If the source is not obvious then I would recommend a re test after you have taken possession of the home.
Keep in mind these two tests are considered preliminary air quality tests. The tests I am performing are NOT actual air quality tests.
An air quality test uses a pump to push air through a material that is later sent to a lab where the particulate is identified and counted. The lab report identifies the actual particulate.
So to sum it up, the tests that I am performing will measure the amount of particulate in the air, the amount of VOCs and formaldehyde. Air quality testing where a lab is involved will identify what kind of particulate is in the sampled air. If the amount of particulate and VOCs are typically low, then identifying that actual particulate in my opinion is not necessary in most cases and costing you money for nothing.
These tests are carried out primarily to ensure the building has acceptable air exchange. Air quality testing evolving a lab can range from $400 – $2000. The testing that I perform gives you a good starting point without any additional expense!
What about radon testing?
Only long term monitoring will tell you if you and your family are safe from the harmful side effects of radon. Unfortunately there is no test that can be performed in the time frame of a home inspection that can definitively identify that there is no radon present. Once you have moved in you should carry out a long term radon test. Here is one example of a test approved in Canada.
