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If you suspect that the air quality in your home is poor, you should hire a professional who can test the air quality and give you an informed recommendation. Ask friends, realtors, or construction companies for referrals to a qualified specialist in your area. A professional will be able to test for degraded air due to:  Indoor mold Lead-based paint Dust particles and other allergens Smoke-related air pollution Air fresheners, candles, and incense Household cleaners Combustion particles or gases If you suspect that you have significant levels of radon in your home, you'll need to hire a professional to resolve the issue. You can contact your state or local health department for a list of recommended professionals who can help clear the radon out of your home. You can also use the Environmental Protection Agency's interactive map to find a qualified radon professional in your area: https://www.epa.gov/radon/find-information-about-local-radon-zones-and-state-contact-information If you are buying or selling a home, often testing the air for pollutants is a contingency of the loan you will be applying for. This is especially true in regions that have high levels of air pollution due to industry or even natural causes (like the common occurrence of forest fires). In these cases, at-home tests that you complete yourself will not be sufficient.  Hire a professional that has experience testing air quality in homes, preferably one that is recommended by your realtor, lender, or home inspector. If you don't have a recommendation for a professional, try to do some online research by reading online reviews from actual customers of various professionals in your areas. You can also check a prospective professional for certifications in the field – such as membership in the Indoor Air Quality Association or the International Association of Certified Indoor Air Consultants.
Pay a professional to test the air quality in your home. Hire a radon specialist to test for radon in your home. Use a professional test if you need an official test result.