How often should well water be tested for radon? By ProMatcher Staff Updated: 08/23/2016 Get Free Quotes Today! Answer: Same as the air. At least every 2 years Mass Radon Answer: Every other year unless otherwise recommended by the tester. Worsley Inspections LLC Answer: water test kits Alabama indoor air quality testing, LLC. Get Free Quotes From Local Pros ProMatcher Get Free Quotes Today! Find Local Pros Free Radon Gas Testing Cost Estimates Related Questions Should well water be tested for radon?Top answer: Yes How do I test for radon gas? How often should I test my home for radon?Top answer: Every other year What is Radon? How Much Does a Radon Inspection Cost?