Radon testing in Nashua, Manchester & nearby NH towns
Testing is the only way to know your home’s radon level. You can do it yourself (New Hampshire even offers free kits) or hire a professional — here’s how to choose.
Short-term vs. long-term tests
| Type | Length | Good for |
|---|---|---|
| Short-term | 2 to 90 days | A quick reading; real estate deadlines |
| Long-term | More than 91 days, up to a year | The best picture of your year-round average |
Source: NH DHHS. Short-term devices include charcoal kits and continuous monitors; long-term options include alpha-track kits. Radon rises and falls day to day and season to season, so a long-term test gives a truer average.
Free do-it-yourself kits for NH residents
The New Hampshire Radon Program provides free short-term test kits to state residents. Order one from the state’s kit page. (NHDES announcement) NH DHHS also runs a program with participating public libraries that lend handheld radon monitors. (NH DHHS)
Tips: test in the lowest lived-in level, keep the kit away from drafts, windows, and humid spots like bathrooms, and follow the timing instructions exactly.
Testing for a home sale
For real estate, NH DHHS describes using two test devices side by side (at least 4 inches apart) and averaging them; if the two disagree a lot, retest. Certification isn’t legally required for testing in NH, but the state recommends a nationally certified measurement professional, especially in a transaction. (NH DHHS)
Testing your well water
If you’re on a private well, test the water too. NHDES recommends at least two water tests, ideally a month apart, before deciding on treatment — results vary a lot from sample to sample. Because bedrock wells with high radon are more likely to have uranium or other radionuclides, NHDES also suggests testing for uranium and gross alpha. (NHDES)
What do the numbers mean?
- 4 pCi/L or higher (air): EPA recommends fixing your home.
- 2 to 4 pCi/L: EPA suggests considering a fix — there is no known completely safe level.
- Below 2 pCi/L: Retest occasionally and after renovations, such as finishing a basement. (EPA Citizen’s Guide)
High result? Read about radon mitigation or request a quote.
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