Radon test results in every Worcester County town
The Massachusetts Department of Public Health collects residential radon results from certified labs. Across Worcester County, labs reported 63,361 tests from 2016 through 2025. About 35.7% of them came back at or above the EPA action level of 4 pCi/L. Every one of the county's 60 cities and towns had results at or above that level.
| Town | Tests reported (2016–2025) | Share at or above 4 pCi/L |
|---|---|---|
| Ashburnham | 476 | 49.8% |
| Athol | 417 | 28.8% |
| Auburn | 1,593 | 45.6% |
| Barre | 264 | 17.0% |
| Berlin | 439 | 31.2% |
| Blackstone | 683 | 17.7% |
| Bolton | 1,141 | 35.5% |
| Boylston | 795 | 50.9% |
| Brookfield | 277 | 23.8% |
| Charlton | 1,135 | 44.8% |
| Clinton | 945 | 23.8% |
| Douglas | 840 | 42.7% |
| Dudley | 923 | 57.9% |
| East Brookfield | 135 | 25.9% |
| Fitchburg | 1,554 | 36.2% |
| Gardner | 768 | 24.7% |
| Grafton | 2,353 | 33.1% |
| Hardwick | 105 | 10.5% |
| Harvard | 1,033 | 43.1% |
| Holden | 2,531 | 42.7% |
| Hopedale | 579 | 14.5% |
| Hubbardston | 259 | 35.1% |
| Lancaster | 745 | 39.9% |
| Leicester | 974 | 59.1% |
| Leominster | 2,138 | 30.2% |
| Lunenburg | 1,045 | 45.8% |
| Mendon | 595 | 24.4% |
| Milford | 2,354 | 18.0% |
| Millbury | 1,242 | 33.2% |
| Millville | 204 | 15.2% |
| New Braintree fewer than 100 tests; read with caution | 41 | 24.4% |
| North Brookfield | 217 | 21.2% |
| Northborough | 1,984 | 31.2% |
| Northbridge | 1,663 | 37.2% |
| Oakham | 137 | 44.5% |
| Oxford | 1,132 | 49.6% |
| Paxton | 562 | 43.6% |
| Petersham fewer than 100 tests; read with caution | 77 | 22.1% |
| Phillipston fewer than 100 tests; read with caution | 75 | 22.7% |
| Princeton | 472 | 38.1% |
| Royalston fewer than 100 tests; read with caution | 55 | 36.4% |
| Rutland | 895 | 45.6% |
| Shrewsbury | 3,971 | 40.7% |
| Southborough | 1,451 | 30.3% |
| Southbridge | 765 | 20.8% |
| Spencer | 809 | 37.8% |
| Sterling | 821 | 45.9% |
| Sturbridge | 1,012 | 18.9% |
| Sutton | 1,100 | 36.1% |
| Templeton | 342 | 23.1% |
| Upton | 1,118 | 31.8% |
| Uxbridge | 1,564 | 30.8% |
| Warren | 190 | 10.0% |
| Webster | 1,178 | 48.6% |
| West Boylston | 852 | 43.8% |
| West Brookfield | 240 | 14.6% |
| Westborough | 2,074 | 29.4% |
| Westminster | 642 | 45.6% |
| Winchendon | 415 | 28.2% |
| Worcester | 8,965 | 35.6% |
Source: Massachusetts Environmental Public Health Tracking, residential radon data, 2016–2025.
How to read these numbers
- These are tests, not homes. One house can be tested more than once, including after a mitigation system goes in.
- The figures cover homes whose owners chose to test, which may not represent every home in town.
- A town's share can't tell you your own level. Homes on the same street can test very differently. The only way to know is to test.
Once you have a number, read your result.