| Metric | No. of homes reporting (n = 2382) | Average radon level ± SEM, Bq/m3 | Observed radon level, Bq/m3 | |
|---|---|---|---|---|
| Minimum | Maximum | |||
| Year of construction | ||||
| 1890-1939 | 60 | 72 ± 7 | < 15 | 361 |
| 1940-1959 | 174 | 94 ± 7 | < 15 | 722 |
| 1960-1979 | 547 | 120 ± 4 | < 15 | 1100 |
| 1980-1999 | 721 | 106 ± 3 | < 15 | 1069 |
| 2000-2009 | 432 | 132 ± 6 | < 15 | 1274 |
| 2010 or later | 195 | 218 ± 29 | < 15 | 3441 |
| Not reported | 253 | - | ||
| Building type | ||||
| Condominium/apartment | 12 | 81 ± 17 | < 15 | 167 |
| Single-family detached | 1819 | 126 ± 4 | < 15 | 3441 |
| Duplex | 113 | 108 ± 10 | < 15 | 925 |
| Townhouse | 50 | 76 ± 12 | < 15 | 498 |
| Not reported | 388 | 136 ± 6 | < 15 | 1014 |
| Foundation | ||||
| Basement | 1973 | 125 ± 4 | < 15 | 3441 |
| Slab | 28 | 120 ± 21 | < 15 | 472 |
| Bilevel | 89 | 106 ± 6 | < 15 | 309 |
| Crawl space | 30 | 95 ± 20 | < 15 | 607 |
| Not reported | 262 | 144 ± 8 | < 15 | 1014 |
| Floor tested | ||||
| Basement | 1360 | 137 ± 4 | < 15 | 3227 |
| Bilevel | 58 | 91 ± 6 | < 15 | 240 |
| Ground | 485 | 62 ± 4 | < 15 | 1005 |
| First | 246 | 101 ± 7 | < 15 | 1274 |
| Second/third | 31 | 92 ± 13 | 17 | 326 |
| Not reported | 202 | 176 ± 22 | 17 | 3441 |
| Room | ||||
| Bedroom | 282 | 125 ± 7 | < 15 | 1198 |
| Living space | 1740 | 117 ± 3 | < 15 | 2346 |
| Utility space | 105 | 224 ± 48 | < 15 | 3441 |
| Not reported | 255 | 147 ± 8 | < 15 | 1014 |
| Total | 2382 | 127 ± 3 | < 15 | 3441 |
Note: SEM = standard error of the mean.