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Test for radon where relevant

Radon is a radioactive soil gas that can build up in tight houses. Testing is cheap and the only way to know your level.

How

1. Test the lowest lived-in level, about 3 ft (0.9 m) off the floor in the middle of a room.
2. Use a short-term kit for a first check and a long-term (over 90 days) kit for a year-round average.
3. The US EPA action level is 4 pCi/L (150 Bq/m3); it suggests considering a fix between 2 and 4 pCi/L (75 to 150 Bq/m3). Check your own country's reference level.
4. If high, hire a licensed mitigation professional and retest a few months after the fix.
5. Retest after renovations or if you start using a basement as living space.

Sources

1. What is EPA's Action Level for Radon and What Does it Mean?. U.S. Environmental Protection Agency, accessed 2026-11
2. Testing for Radon in Your Home. U.S. Centers for Disease Control and Prevention, accessed 2026-11

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