Indoor Air Pollution and Testing

Indoor pollution can stem from a variety of sources, externally from the air outside, but it can also
originate from indoors. This may become particularly problematic during colder seasons when we seal
up our homes to conserve heat.

Let’s quickly review some of the most common air pollutants. We’ll cover how these pollutants can be
detected as well as what to do about them if you do detect them.

Gases from combustion

Combustion devices such as cookstoves, heating stoves, fireplaces, and space heaters, can release
deadly pollutants such as carbon monoxide (CO) and nitrogen dioxide (NO2) into the atmosphere. CO
can lead to a variety of symptoms such as headaches, nausea, and even death. Around 500 people in the
U.S die from exposure to CO every year. Because it is odorless and without color, the best way to detect
the gas is by installing CO detectors near bedrooms and near combustion appliances. NO2 can lead to
shortness of breath, and long-term exposure can lead to more serious complications such as infection or
emphysema. Unlike CO, NO2 is easier to detect because it has a reddish-brown color and produces an acrid
odor. NO2 detectors can still be useful for detecting low levels.
Radon is another gas difficult to detect because it has no color and it is odorless. Unfortunately, it is also
very dangerous, causing lung cancer and responsible for the deaths of around 20 thousand Americans
every year. Soil usually contains trace amounts of decaying uranium, which emits radon. Usually it
dissipates in the air, harmlessly, but it can also flow into buildings through gaps and can reach dangerous
levels in the lower floors of a building.


Much like radon, asbestos can be found naturally in soil. It was also commonly used as a building
material prior to around 1980. This is why that if you’re living in an old building it may be a good idea to
test for asbestos. Along with causing lung cancer, it can lead to long-term lung scarring and
mesothelioma. Because the risks are so high, when you’re checking for asbestos it’s advised that you
contact a professional to do your testing for you.


Mold grows in damp, human conditions in the presence of a wide range of organic material such as
wood, carpet, upholstery, and an infestation can take root in places you’re not able to see, such as
behind walls. Symptoms of exposure to mold can vary from coughing, wheezing, headache, and skin
irritation. It can also exacerbate underlying respiratory issues such as for people who have asthma. Be
wary of areas in your home that is quick to accumulate moisture, such as around pipes or in bathrooms.
You may not be able to see mold but you may be able to smell it. If you suspect you may have mold,
contacting a professional is usually your best bet. Be careful of using do it yourself mold testing kits, as
they are often inaccurate and are difficult to interpret.