2023 Edition

The Air Quality Test Guide

The Air Quality Test Summary
What: Indoor air quality testing determines whether pollutants are present in the air in sufficient quantities to pose health risks.
Who: Tests can be performed by a resident, or conducted by a professional.
Where: Testing is done inside the building or room where the air quality is in question.
When: Testing can be done anytime, but may take several days. Certain conditions should normally be met before tests are conducted, however.
How: Air quality tests are typically done by sampling the air or surfaces of a home over a specified period of time.
Type: Multiple tests are on the market and available professionally, depending on whether the tester is screening against a specific problem or multiple possibilities.
Why: Air quality testing ensures the air in a building is healthful.
Time: An air quality test may take several days to complete, depending on the type of test used.
Language: Varies.
Preparation: An assessment of the location should usually be done to get an idea of whether testing is necessary and what might be done if the test found a contaminant.
Cost: Air quality tests may be free in some circumstances. Others cost as little as $10. Thorough professional tests can cost several hundred dollars.

By Beau Johnson, Tests.com Contributing Writer

Because we spend every moment of our lives breathing, and most of us spend the vast majority of our lives indoors, it’s very important that we know the air is clean and healthy. An indoor air quality test can help ensure that there is nothing contaminating the air that might endanger health. A few of the most troublesome pollutant categories include harmful or unbalanced gases, microbes, and airborne particles. Fortunately, there is a test out there designed to detect them all.

Testing at Businesses or Public Buildings

Testing should be done in work places if there is a strong suspicion of air contamination. If, for example, an employee has chronic respiratory symptoms while at work that alleviate when they leave the office, and have checked for and removed possible irritants (indoor plants, smoke, perfume, mold growth), then the office should consider requesting an air quality test.

The National Institute for Occupational Safety and Health will conduct a Health Hazard Evaluation if a request is made and circumstances warrant. However, such testing is complicated and should not be done before other precautionary steps are taken. The Connecticut Department of Public Health, for instance, advises that air pollutants are found everywhere on “background” levels, meaning that they are not present in sufficient quantities to negatively affect health in most individuals. Air quality tests will always find some of these pollutants, though. Regulatory agencies also recommend having a plan for what could be done if a problem was detected. Haphazardly testing air without a strong indication of a specific problem and a plan to remedy it could just confuse the situation.

In Homes

Home testing or monitoring is less of a sticking point. Because homeowners are usually solely responsible for the air quality in the home and the health of the occupants, some air quality control is a must. And if there is an allergy, sinus or asthma sufferer in the house, or a specific air quality risk to protect against, testing is an especially good idea. Again, there are common-sense approaches to protecting air quality, such as removing pollutants, addressing leaks, and maintaining general cleanliness that should be done before testing for specific air quality problems.

Test Types

There are almost as many air quality tests as there are possible air contaminants. Many tests are designed to pick up multiple contaminants, however. Most tests are either air samples, bulk samples, or surface samples. Air samples assess the air inside a building, and some compare the inside air to the air outside. Bulk samples are material from a contaminated area used to identify the contaminant (typically mold). Surface samples test the amount of spores or microbes on an indoor surface using a swab, tape, or a Petri-type dish. Some of the most practical tests are designed to detect carbon monoxide, radon, and microbes such as mold, mildew, bacteria and fungi.

Carbon Monoxide

Every home should be equipped with a carbon monoxide detector. Carbon monoxide is a colorless odorless gas that if inhaled, deprives the brain of oxygen, leading to nausea, unconsciousness, and even death. It originates from the incomplete combustion of fossil fuels, and can be leaked from heaters and other appliances. A carbon monoxide detector can be purchased for as little as $10, and emits an alarm sound when the presence of carbon monoxide is detected.


Radon is another colorless, odorless, tasteless gas that is produced by the breakdown of uranium in the earth. The gas seeping into homes causes a greatly increased risk of lung cancer. The EPA recommends that all homes test for radon. The agency also provides maps to help people determine whether they live in an area with high risk of radon exposure. Radon tests are either passive or active—passive tests are simply opened and left in your home for a period of time to record radon levels. They are then sent to a laboratory for analysis. Active testing uses a powered device that continuously tracks radon levels in your home. Professional testing is also an option, and can sometimes be included in a general home inspection. Costs of radon testing range from $10 and up for self-testing kits, and anywhere from $50 to over $300 is common for professionals.

For more detailed information on radon testing, take a look at our full Guide to Radon Tests.


The simplest test for mold and mildew is one someone conducts with their eyes. People concerned about mold should look for staining or fuzzy growths on building materials and furniture, especially around known leaks or in high-moisture areas (including air conditioners and heaters). If mold or mildew is suspected without a visible source, a kit can be attained to test for the problem. While a bulk sample test may be used to determine if a type of mold is especially toxic, most mold and mildew tests are air or surface sample tests. Some can be self-read and others are meant to be returned for laboratory analysis after the sampling is complete. These tests will determine whether contaminants are present in abnormally high quantities. Tests for mold and other irritants can cost as little as $10, but there are other tests that start in the $30-range and go beyond $100 that test for multiple contaminants also, such as yeast, fungus, and harmful bacteria (such as Legionella). Home air can also be professionally analyzed, which can cost several hundred dollars. Should one decide to take this step, they should make sure that the tester is certified by the American Indoor Air Quality Council, the only organization that provides accredited certifications.

Interesting in an air quality test? Check out our Air Quality Test Directory. To learn more about air quality testing, read our interview with air quality test expert Daniel Friedman.