Radon Levels in Grantham, NH
Grantham is in Sullivan County. Radon data is tracked at the county level by the EPA and CDC.
EPA predicts average indoor levels between 2–4 pCi/L in this county · Source: EPA, CDC
Tipper's take on radon in Grantham
Grantham is in Sullivan County, EPA Zone 2, a moderate risk classification. The EPA predicts average indoor radon levels between 2 and 4 pCi/L here. CDC data from Sullivan County puts the average measured radon level at 3.2 pCi/L.
"Moderate" is the zone people underestimate most. Some homes in Grantham will test at 1 pCi/L, others at 7 pCi/L. The county average doesn't tell you which side your home falls on.
A $15 test kit answers the question for good. If you're below 4 pCi/L, you can stop thinking about it. If you're above, mitigation systems in New Hampshire typically cost $800–$2,000 and work well.
Sources: EPA Radon Zone Map, CDC Environmental Public Health Tracking
Test Your Home in Grantham
A short-term test kit costs about $15, includes the lab fee, and gives you a result in 48 hours. It's the only way to know your home's actual radon level.
Radon Professionals Serving New Hampshire
No contractors in our directory are listed specifically for Grantham. These certified pros serve New Hampshire and may cover your area.
Full County Data
Radon data is tracked at the county level. For state comparisons, nearby counties, and detailed analysis, see the full county page.
Sullivan County, NH: Full Radon Data →Radon FAQ: Grantham, NH
What is the radon risk in Grantham?
Grantham is in Sullivan County, which the EPA classifies as Zone 2 (Moderate risk). The county average is 3.2 pCi/L. The EPA recommends testing every home regardless of zone. Radon levels vary house to house.
How do I test my home in Grantham for radon?
Place a short-term radon test kit in the lowest livable level of your home for 48 hours under closed-house conditions. Kits cost about $15 and include the lab fee. Keep windows and exterior doors closed during the test (normal entry/exit is fine). Results come back in about a week.
What should I do if radon is high in my Grantham home?
If your test result is at or above 4 pCi/L, the EPA recommends installing a mitigation system. A certified contractor can install one for $800–$2,000 in most cases. The system runs continuously and typically brings levels well below 2 pCi/L. Retest after installation to confirm.