Pennsylvania Cities Ranked by Indoor Radon Levels
Measured averages from Airthings devices across Pennsylvania, USA. Action level: 4 pCi/L — the threshold at which remediation is recommended.
Duncannon has the highest measured indoor radon in Pennsylvania at 25.5 pCi/L, based on Airthings measurements across 507 cities.
Updated September 28, 2026
Highest city
25.5pCi/L
Duncannon
Pennsylvania city average
4.6pCi/L
across 507 cities
Above action level
233/ 507
cities
| # | Location | Avg level | vs action level |
|---|---|---|---|
| 1 | Duncannon | 25.5 pCi/L | 6.4× over |
| 2 | Prospect | 17.6 pCi/L | 4.4× over |
| 3 | Sand Hill | 17.6 pCi/L | 4.4× over |
| 4 | Jacobus | 17.3 pCi/L | 4.3× over |
| 5 | Zion | 16.4 pCi/L | 4.1× over |
| 6 | Greenville | 15.0 pCi/L | 3.8× over |
| 7 | Russellton | 14.9 pCi/L | 3.7× over |
| 8 | Kutztown | 14.6 pCi/L | 3.6× over |
| 9 | Palmerton | 14.1 pCi/L | 3.5× over |
| 10 | Apollo | 13.5 pCi/L | 3.4× over |
| 11 | Akron | 13.4 pCi/L | 3.3× over |
| 12 | Georgetown | 13.2 pCi/L | 3.3× over |
| 13 | Shippensburg | 13.2 pCi/L | 3.3× over |
| 14 | Manheim | 13.2 pCi/L | 3.3× over |
| 15 | Grill | 13.1 pCi/L | 3.3× over |
| 16 | Bloomsburg | 12.9 pCi/L | 3.2× over |
| 17 | Sun Valley | 12.8 pCi/L | 3.2× over |
| 18 | Robesonia | 12.4 pCi/L | 3.1× over |
| 19 | Industry | 12.1 pCi/L | 3.0× over |
| 20 | West Hills | 12.0 pCi/L | 3.0× over |
| 21 | Cherryville | 11.7 pCi/L | 2.9× over |
| 22 | Lebanon South | 11.7 pCi/L | 2.9× over |
| 23 | Lewistown | 11.7 pCi/L | 2.9× over |
| 24 | Shrewsbury | 11.7 pCi/L | 2.9× over |
| 25 | Hughesville | 11.6 pCi/L | 2.9× over |
| 26 | Quarryville | 11.5 pCi/L | 2.9× over |
| 27 | Strasburg | 11.3 pCi/L | 2.8× over |
| 28 | Centre Hall | 11.3 pCi/L | 2.8× over |
| 29 | Cementon | 11.2 pCi/L | 2.8× over |
| 30 | Wrightsville | 11.2 pCi/L | 2.8× over |
| 31 | Stewartstown | 10.7 pCi/L | 2.7× over |
| 32 | Factoryville | 10.6 pCi/L | 2.6× over |
| 33 | Rutherford | 10.2 pCi/L | 2.6× over |
| 34 | Mountville | 10.2 pCi/L | 2.6× over |
| 35 | Spry | 10.1 pCi/L | 2.5× over |
| 36 | Beaver Falls | 9.9 pCi/L | 2.5× over |
| 37 | Windsor | 9.9 pCi/L | 2.5× over |
| 38 | Glen Rock | 9.8 pCi/L | 2.4× over |
| 39 | Sinking Spring | 9.8 pCi/L | 2.4× over |
| 40 | Riverside | 9.7 pCi/L | 2.4× over |
| 41 | West Lawn | 9.4 pCi/L | 2.4× over |
| 42 | Cornwall | 9.3 pCi/L | 2.3× over |
| 43 | Effort | 9.3 pCi/L | 2.3× over |
| 44 | Parkville | 9.2 pCi/L | 2.3× over |
| 45 | Susquehanna Trails | 9.1 pCi/L | 2.3× over |
| 46 | Garden View | 9.1 pCi/L | 2.3× over |
| 47 | Smethport | 8.9 pCi/L | 2.2× over |
| 48 | Shanor-Northvue | 8.9 pCi/L | 2.2× over |
| 49 | Lititz | 8.7 pCi/L | 2.2× over |
| 50 | Penbrook | 8.7 pCi/L | 2.2× over |
| 51 | Palmyra | 8.6 pCi/L | 2.2× over |
| 52 | Honey Brook | 8.5 pCi/L | 2.1× over |
| 53 | Lake Wynonah | 8.5 pCi/L | 2.1× over |
| 54 | Red Lion | 8.4 pCi/L | 2.1× over |
| 55 | Shiremanstown | 8.4 pCi/L | 2.1× over |
| 56 | East Petersburg | 8.2 pCi/L | 2.1× over |
| 57 | Pine Grove Mills | 8.1 pCi/L | 2.0× over |
| 58 | Millersburg | 8.1 pCi/L | 2.0× over |
| 59 | Freeport | 8.0 pCi/L | 2.0× over |
| 60 | Marysville | 8.0 pCi/L | 2.0× over |
| 61 | Summit Hill | 7.9 pCi/L | 2.0× over |
| 62 | Cressona | 7.9 pCi/L | 2.0× over |
| 63 | Montrose | 7.8 pCi/L | 2.0× over |
| 64 | Mount Joy | 7.8 pCi/L | 1.9× over |
| 65 | Mount Holly Springs | 7.8 pCi/L | 1.9× over |
| 66 | Light Street | 7.6 pCi/L | 1.9× over |
| 67 | Carnegie | 7.6 pCi/L | 1.9× over |
| 68 | Elysburg | 7.5 pCi/L | 1.9× over |
| 69 | Jefferson Hills | 7.5 pCi/L | 1.9× over |
| 70 | Skyline View | 7.5 pCi/L | 1.9× over |
| 71 | Hummelstown | 7.4 pCi/L | 1.8× over |
| 72 | Nazareth | 7.3 pCi/L | 1.8× over |
| 73 | Paoli | 7.3 pCi/L | 1.8× over |
| 74 | Somerset | 7.3 pCi/L | 1.8× over |
| 75 | Calumet | 7.2 pCi/L | 1.8× over |
| 76 | Lakemont | 7.1 pCi/L | 1.8× over |
| 77 | Breinigsville | 7.0 pCi/L | 1.8× over |
| 78 | Allentown | 7.0 pCi/L | 1.8× over |
| 79 | Cleona | 6.9 pCi/L | 1.7× over |
| 80 | Myerstown | 6.9 pCi/L | 1.7× over |
| 81 | Northumberland | 6.9 pCi/L | 1.7× over |
| 82 | Valley View | 6.9 pCi/L | 1.7× over |
| 83 | Houserville | 6.9 pCi/L | 1.7× over |
| 84 | Fountain Hill | 6.8 pCi/L | 1.7× over |
| 85 | Mifflintown | 6.8 pCi/L | 1.7× over |
| 86 | Slatington | 6.7 pCi/L | 1.7× over |
| 87 | Brodheadsville | 6.6 pCi/L | 1.6× over |
| 88 | Clay | 6.6 pCi/L | 1.6× over |
| 89 | Mechanicsburg | 6.6 pCi/L | 1.6× over |
| 90 | Colonial Park | 6.5 pCi/L | 1.6× over |
| 91 | Abbottstown | 6.5 pCi/L | 1.6× over |
| 92 | York | 6.5 pCi/L | 1.6× over |
| 93 | Dorneyville | 6.5 pCi/L | 1.6× over |
| 94 | Wernersville | 6.4 pCi/L | 1.6× over |
| 95 | West Fairview | 6.4 pCi/L | 1.6× over |
| 96 | Murrysville | 6.4 pCi/L | 1.6× over |
| 97 | Zelienople | 6.3 pCi/L | 1.6× over |
| 98 | Emmaus | 6.3 pCi/L | 1.6× over |
| 99 | Ellport | 6.3 pCi/L | 1.6× over |
| 100 | Treasure Lake | 6.3 pCi/L | 1.6× over |
| 101 | Waynesboro | 6.3 pCi/L | 1.6× over |
| 102 | White Oak | 6.3 pCi/L | 1.6× over |
| 103 | Chambersburg | 6.3 pCi/L | 1.6× over |
| 104 | Lawnton | 6.3 pCi/L | 1.6× over |
| 105 | West View | 6.3 pCi/L | 1.6× over |
| 106 | Ben Avon | 6.3 pCi/L | 1.6× over |
| 107 | Millvale | 6.3 pCi/L | 1.6× over |
| 108 | Bath | 6.2 pCi/L | 1.6× over |
| 109 | Hasson Heights | 6.1 pCi/L | 1.5× over |
| 110 | Saylorsburg | 6.1 pCi/L | 1.5× over |
| 111 | Tunkhannock | 6.1 pCi/L | 1.5× over |
| 112 | Back Mountain | 6.0 pCi/L | 1.5× over |
| 113 | Greensburg | 6.0 pCi/L | 1.5× over |
| 114 | Mechanicsville | 6.0 pCi/L | 1.5× over |
| 115 | Clarion | 6.0 pCi/L | 1.5× over |
| 116 | Oley | 5.9 pCi/L | 1.5× over |
| 117 | Spring Grove | 5.9 pCi/L | 1.5× over |
| 118 | Saxonburg | 5.9 pCi/L | 1.5× over |
| 119 | Annville | 5.9 pCi/L | 1.5× over |
| 120 | Mars | 5.8 pCi/L | 1.5× over |
| 121 | Milton | 5.8 pCi/L | 1.5× over |
| 122 | Lawson Heights | 5.8 pCi/L | 1.4× over |
| 123 | Allison Park | 5.8 pCi/L | 1.4× over |
| 124 | Boalsburg | 5.7 pCi/L | 1.4× over |
| 125 | Lebanon | 5.7 pCi/L | 1.4× over |
| 126 | Old Orchard | 5.7 pCi/L | 1.4× over |
| 127 | Bradford Woods | 5.7 pCi/L | 1.4× over |
| 128 | Manchester | 5.7 pCi/L | 1.4× over |
| 129 | New Holland | 5.7 pCi/L | 1.4× over |
| 130 | Columbia | 5.6 pCi/L | 1.4× over |
| 131 | Biglerville | 5.6 pCi/L | 1.4× over |
| 132 | Chicora | 5.6 pCi/L | 1.4× over |
| 133 | Saint Marys | 5.6 pCi/L | 1.4× over |
| 134 | Horsham | 5.5 pCi/L | 1.4× over |
| 135 | Lower Allen | 5.5 pCi/L | 1.4× over |
| 136 | Youngsville | 5.5 pCi/L | 1.4× over |
| 137 | Trexlertown | 5.5 pCi/L | 1.4× over |
| 138 | Guilford | 5.5 pCi/L | 1.4× over |
| 139 | Progress | 5.5 pCi/L | 1.4× over |
| 140 | Middletown | 5.5 pCi/L | 1.4× over |
| 141 | New Berlinville | 5.5 pCi/L | 1.4× over |
| 142 | Landisville | 5.4 pCi/L | 1.4× over |
| 143 | South Coatesville | 5.3 pCi/L | 1.3× over |
| 144 | Paxtonia | 5.3 pCi/L | 1.3× over |
| 145 | Loganville | 5.3 pCi/L | 1.3× over |
| 146 | Homeacre-Lyndora | 5.3 pCi/L | 1.3× over |
| 147 | Mercersburg | 5.3 pCi/L | 1.3× over |
| 148 | Spring City | 5.3 pCi/L | 1.3× over |
| 149 | Clarks Summit | 5.3 pCi/L | 1.3× over |
| 150 | Stormstown | 5.3 pCi/L | 1.3× over |
| 151 | Coatesville | 5.2 pCi/L | 1.3× over |
| 152 | Linntown | 5.2 pCi/L | 1.3× over |
| 153 | Monroeville | 5.2 pCi/L | 1.3× over |
| 154 | Bally | 5.2 pCi/L | 1.3× over |
| 155 | Hershey | 5.2 pCi/L | 1.3× over |
| 156 | Schlusser | 5.2 pCi/L | 1.3× over |
| 157 | McMurray | 5.2 pCi/L | 1.3× over |
| 158 | Parkesburg | 5.2 pCi/L | 1.3× over |
| 159 | Millersville | 5.2 pCi/L | 1.3× over |
| 160 | Ambridge | 5.1 pCi/L | 1.3× over |
| 161 | Cecil-Bishop | 5.1 pCi/L | 1.3× over |
| 162 | Easton | 5.1 pCi/L | 1.3× over |
| 163 | Boiling Springs | 5.0 pCi/L | 1.3× over |
| 164 | Elizabethtown | 4.9 pCi/L | 1.2× over |
| 165 | Franklin Park | 4.9 pCi/L | 1.2× over |
| 166 | Lancaster | 4.9 pCi/L | 1.2× over |
| 167 | Bellefonte | 4.9 pCi/L | 1.2× over |
| 168 | Butler | 4.9 pCi/L | 1.2× over |
| 169 | Willow Street | 4.9 pCi/L | 1.2× over |
| 170 | Stonybrook | 4.8 pCi/L | 1.2× over |
| 171 | Monaca | 4.8 pCi/L | 1.2× over |
| 172 | Emsworth | 4.8 pCi/L | 1.2× over |
| 173 | Camp Hill | 4.8 pCi/L | 1.2× over |
| 174 | Spring Ridge | 4.8 pCi/L | 1.2× over |
| 175 | Enola | 4.8 pCi/L | 1.2× over |
| 176 | Aliquippa | 4.7 pCi/L | 1.2× over |
| 177 | Hanover | 4.7 pCi/L | 1.2× over |
| 178 | Etna | 4.7 pCi/L | 1.2× over |
| 179 | Berwyn | 4.6 pCi/L | 1.2× over |
| 180 | Ephrata | 4.6 pCi/L | 1.2× over |
| 181 | Fleetwood | 4.6 pCi/L | 1.2× over |
| 182 | Stony Creek Mills | 4.6 pCi/L | 1.2× over |
| 183 | Oreland | 4.6 pCi/L | 1.1× over |
| 184 | Wescosville | 4.6 pCi/L | 1.1× over |
| 185 | Arlington Heights | 4.5 pCi/L | 1.1× over |
| 186 | Carnot-Moon | 4.5 pCi/L | 1.1× over |
| 187 | Radnor | 4.5 pCi/L | 1.1× over |
| 188 | Weigelstown | 4.5 pCi/L | 1.1× over |
| 189 | Swissvale | 4.5 pCi/L | 1.1× over |
| 190 | Cranberry Township | 4.5 pCi/L | 1.1× over |
| 191 | Stroudsburg | 4.5 pCi/L | 1.1× over |
| 192 | Canonsburg | 4.4 pCi/L | 1.1× over |
| 193 | Mansfield | 4.4 pCi/L | 1.1× over |
| 194 | Churchville | 4.4 pCi/L | 1.1× over |
| 195 | Northampton | 4.4 pCi/L | 1.1× over |
| 196 | Churchill | 4.4 pCi/L | 1.1× over |
| 197 | Eastlawn Gardens | 4.4 pCi/L | 1.1× over |
| 198 | Littlestown | 4.4 pCi/L | 1.1× over |
| 199 | Matamoras | 4.4 pCi/L | 1.1× over |
| 200 | Gold Key Lake | 4.4 pCi/L | 1.1× over |
| 201 | Hokendauqua | 4.4 pCi/L | 1.1× over |
| 202 | Schnecksville | 4.4 pCi/L | 1.1× over |
| 203 | Pleasant Hills | 4.4 pCi/L | 1.1× over |
| 204 | Sewickley | 4.3 pCi/L | 1.1× over |
| 205 | Dillsburg | 4.3 pCi/L | 1.1× over |
| 206 | Boyertown | 4.3 pCi/L | 1.1× over |
| 207 | Nixon | 4.3 pCi/L | 1.1× over |
| 208 | Fernway | 4.3 pCi/L | 1.1× over |
| 209 | Fox Chapel | 4.2 pCi/L | 1.1× over |
| 210 | Ambler | 4.2 pCi/L | 1.1× over |
| 211 | Burgettstown | 4.2 pCi/L | 1.1× over |
| 212 | Greencastle | 4.2 pCi/L | 1.1× over |
| 213 | Huntingdon | 4.2 pCi/L | 1.1× over |
| 214 | Chevy Chase Heights | 4.2 pCi/L | 1.1× over |
| 215 | Duboistown | 4.2 pCi/L | 1.1× over |
| 216 | Rennerdale | 4.2 pCi/L | 1.1× over |
| 217 | New Castle Northwest | 4.2 pCi/L | 1.0× over |
| 218 | Elverson | 4.2 pCi/L | 1.0× over |
| 219 | Latrobe | 4.2 pCi/L | 1.0× over |
| 220 | Coraopolis | 4.2 pCi/L | 1.0× over |
| 221 | Oakmont | 4.2 pCi/L | 1.0× over |
| 222 | Plum | 4.2 pCi/L | 1.0× over |
| 223 | Dover | 4.1 pCi/L | 1.0× over |
| 224 | Glenside | 4.1 pCi/L | 1.0× over |
| 225 | Jersey Shore | 4.1 pCi/L | 1.0× over |
| 226 | Yorklyn | 4.1 pCi/L | 1.0× over |
| 227 | Conyngham | 4.1 pCi/L | 1.0× over |
| 228 | Gastonville | 4.1 pCi/L | 1.0× over |
| 229 | Level Green | 4.0 pCi/L | 1.0× over |
| 230 | Edgewood | 4.0 pCi/L | 1.0× over |
| 231 | Raubsville | 4.0 pCi/L | 1.0× over |
| 232 | Crafton | 4.0 pCi/L | 1.0× over |
| 233 | Emigsville | 4.0 pCi/L | 1.0× over |
| ✓ Below EPA action level (4 pCi/L) | |||
| 234 | Amity Gardens | 4.0 pCi/L | 1.0× under |
| 235 | Muse | 4.0 pCi/L | 1.0× under |
| 236 | Harrisburg | 3.9 pCi/L | 1.0× under |
| 237 | State College | 3.9 pCi/L | 1.0× under |
| 238 | Seven Fields | 3.9 pCi/L | 1.0× under |
| 239 | Mountain Top | 3.9 pCi/L | 1.0× under |
| 240 | Spring House | 3.9 pCi/L | 1.0× under |
| 241 | Downingtown | 3.9 pCi/L | 1.0× under |
| 242 | New Cumberland | 3.8 pCi/L | 1.0× under |
| 243 | Gibsonia | 3.8 pCi/L | 0.9× under |
| 244 | Wyomissing Hills | 3.8 pCi/L | 0.9× under |
| 245 | Carlisle | 3.7 pCi/L | 0.9× under |
| 246 | East Stroudsburg | 3.7 pCi/L | 0.9× under |
| 247 | Jenkintown | 3.7 pCi/L | 0.9× under |
| 248 | Eagleville | 3.7 pCi/L | 0.9× under |
| 249 | Meridian | 3.7 pCi/L | 0.9× under |
| 250 | New Freedom | 3.7 pCi/L | 0.9× under |
| 251 | Valley Green | 3.7 pCi/L | 0.9× under |
| 252 | Wayne | 3.7 pCi/L | 0.9× under |
| 253 | Lemont | 3.7 pCi/L | 0.9× under |
| 254 | North Wales | 3.7 pCi/L | 0.9× under |
| 255 | Beaver | 3.6 pCi/L | 0.9× under |
| 256 | Lawrence Park | 3.6 pCi/L | 0.9× under |
| 257 | South Uniontown | 3.6 pCi/L | 0.9× under |
| 258 | Ingram | 3.6 pCi/L | 0.9× under |
| 259 | Roaring Spring | 3.6 pCi/L | 0.9× under |
| 260 | Fox Run | 3.5 pCi/L | 0.9× under |
| 261 | Sanatoga | 3.5 pCi/L | 0.9× under |
| 262 | Fairview | 3.5 pCi/L | 0.9× under |
| 263 | Thorndale | 3.5 pCi/L | 0.9× under |
| 264 | East Berlin | 3.5 pCi/L | 0.9× under |
| 265 | Hemlock Farms | 3.5 pCi/L | 0.9× under |
| 266 | Jim Thorpe | 3.5 pCi/L | 0.9× under |
| 267 | McDonald | 3.5 pCi/L | 0.9× under |
| 268 | Enlow | 3.5 pCi/L | 0.9× under |
| 269 | Bryn Mawr | 3.5 pCi/L | 0.9× under |
| 270 | Pottsville | 3.4 pCi/L | 0.9× under |
| 271 | Palmer Heights | 3.4 pCi/L | 0.9× under |
| 272 | Tatamy | 3.4 pCi/L | 0.9× under |
| 273 | Bethlehem | 3.4 pCi/L | 0.9× under |
| 274 | Milford | 3.4 pCi/L | 0.9× under |
| 275 | Media | 3.4 pCi/L | 0.8× under |
| 276 | Pennsburg | 3.4 pCi/L | 0.8× under |
| 277 | Washington | 3.4 pCi/L | 0.8× under |
| 278 | Throop | 3.4 pCi/L | 0.8× under |
| 279 | Baden | 3.4 pCi/L | 0.8× under |
| 280 | Bridgeville | 3.4 pCi/L | 0.8× under |
| 281 | Gettysburg | 3.4 pCi/L | 0.8× under |
| 282 | Richboro | 3.4 pCi/L | 0.8× under |
| 283 | Indiana | 3.3 pCi/L | 0.8× under |
| 284 | Towamensing Trails | 3.3 pCi/L | 0.8× under |
| 285 | Campbelltown | 3.3 pCi/L | 0.8× under |
| 286 | Langhorne | 3.3 pCi/L | 0.8× under |
| 287 | Scranton | 3.3 pCi/L | 0.8× under |
| 288 | South Park Township | 3.3 pCi/L | 0.8× under |
| 289 | Pocono Ranch Lands | 3.3 pCi/L | 0.8× under |
| 290 | Tinicum | 3.3 pCi/L | 0.8× under |
| 291 | Chalfont | 3.3 pCi/L | 0.8× under |
| 292 | Hollidaysburg | 3.3 pCi/L | 0.8× under |
| 293 | McSherrystown | 3.3 pCi/L | 0.8× under |
| 294 | Newtown Grant | 3.3 pCi/L | 0.8× under |
| 295 | Williamsport | 3.2 pCi/L | 0.8× under |
| 296 | Brittany Farms-Highlands | 3.2 pCi/L | 0.8× under |
| 297 | Birdsboro | 3.2 pCi/L | 0.8× under |
| 298 | Conshohocken | 3.2 pCi/L | 0.8× under |
| 299 | Lake Meade | 3.2 pCi/L | 0.8× under |
| 300 | Oakdale | 3.2 pCi/L | 0.8× under |
| 301 | Springdale | 3.2 pCi/L | 0.8× under |
| 302 | Sturgeon | 3.2 pCi/L | 0.8× under |
| 303 | New Hope | 3.2 pCi/L | 0.8× under |
| 304 | Shiloh | 3.2 pCi/L | 0.8× under |
| 305 | Wyomissing | 3.1 pCi/L | 0.8× under |
| 306 | Glenshaw | 3.1 pCi/L | 0.8× under |
| 307 | Skippack | 3.1 pCi/L | 0.8× under |
| 308 | Morrisville | 3.1 pCi/L | 0.8× under |
| 309 | Grove City | 3.1 pCi/L | 0.8× under |
| 310 | Tannersville | 3.1 pCi/L | 0.8× under |
| 311 | Bakerstown | 3.1 pCi/L | 0.8× under |
| 312 | Edgeworth | 3.1 pCi/L | 0.8× under |
| 313 | Macungie | 3.1 pCi/L | 0.8× under |
| 314 | Trooper | 3.1 pCi/L | 0.8× under |
| 315 | Manor | 3.1 pCi/L | 0.8× under |
| 316 | Village Shires | 3.1 pCi/L | 0.8× under |
| 317 | Caln | 3.0 pCi/L | 0.8× under |
| 318 | Brownstown | 3.0 pCi/L | 0.8× under |
| 319 | Evans City | 3.0 pCi/L | 0.8× under |
| 320 | South Waverly | 3.0 pCi/L | 0.7× under |
| 321 | Braddock Hills | 3.0 pCi/L | 0.7× under |
| 322 | Scotland | 3.0 pCi/L | 0.7× under |
| 323 | Tyrone | 3.0 pCi/L | 0.7× under |
| 324 | Moscow | 3.0 pCi/L | 0.7× under |
| 325 | Wilkinsburg | 3.0 pCi/L | 0.7× under |
| 326 | Upper Saint Clair | 2.9 pCi/L | 0.7× under |
| 327 | North Catasauqua | 2.9 pCi/L | 0.7× under |
| 328 | Spinnerstown | 2.9 pCi/L | 0.7× under |
| 329 | Forest Hills | 2.9 pCi/L | 0.7× under |
| 330 | Coopersburg | 2.9 pCi/L | 0.7× under |
| 331 | Imperial | 2.9 pCi/L | 0.7× under |
| 332 | New Oxford | 2.9 pCi/L | 0.7× under |
| 333 | Plumsteadville | 2.9 pCi/L | 0.7× under |
| 334 | Delmont | 2.9 pCi/L | 0.7× under |
| 335 | Devon | 2.8 pCi/L | 0.7× under |
| 336 | Mifflinburg | 2.8 pCi/L | 0.7× under |
| 337 | Chester Springs | 2.8 pCi/L | 0.7× under |
| 338 | Cheswick | 2.8 pCi/L | 0.7× under |
| 339 | Bellevue | 2.8 pCi/L | 0.7× under |
| 340 | Laporte | 2.8 pCi/L | 0.7× under |
| 341 | Harleysville | 2.8 pCi/L | 0.7× under |
| 342 | Trappe | 2.8 pCi/L | 0.7× under |
| 343 | Woxall | 2.8 pCi/L | 0.7× under |
| 344 | Altoona | 2.8 pCi/L | 0.7× under |
| 345 | Thompsonville | 2.8 pCi/L | 0.7× under |
| 346 | Hatfield | 2.8 pCi/L | 0.7× under |
| 347 | Richlandtown | 2.8 pCi/L | 0.7× under |
| 348 | Saw Creek | 2.8 pCi/L | 0.7× under |
| 349 | Shavertown | 2.8 pCi/L | 0.7× under |
| 350 | Penndel | 2.7 pCi/L | 0.7× under |
| 351 | Sharpsburg | 2.7 pCi/L | 0.7× under |
| 352 | Wolfdale | 2.7 pCi/L | 0.7× under |
| 353 | Pocono Pines | 2.7 pCi/L | 0.7× under |
| 354 | Pottsgrove | 2.7 pCi/L | 0.7× under |
| 355 | Harleigh | 2.7 pCi/L | 0.7× under |
| 356 | Pittsburgh | 2.7 pCi/L | 0.7× under |
| 357 | Kulpsville | 2.7 pCi/L | 0.7× under |
| 358 | Paxtang | 2.7 pCi/L | 0.7× under |
| 359 | Brentwood | 2.7 pCi/L | 0.7× under |
| 360 | Halfway House | 2.7 pCi/L | 0.7× under |
| 361 | Schwenksville | 2.7 pCi/L | 0.7× under |
| 362 | Gilbertsville | 2.6 pCi/L | 0.7× under |
| 363 | Honesdale | 2.6 pCi/L | 0.7× under |
| 364 | Mountainhome | 2.6 pCi/L | 0.7× under |
| 365 | Wellsboro | 2.6 pCi/L | 0.7× under |
| 366 | Jeannette | 2.6 pCi/L | 0.7× under |
| 367 | West Chester | 2.6 pCi/L | 0.7× under |
| 368 | Doylestown | 2.6 pCi/L | 0.6× under |
| 369 | Hellertown | 2.6 pCi/L | 0.6× under |
| 370 | Parkside | 2.6 pCi/L | 0.6× under |
| 371 | West Conshohocken | 2.6 pCi/L | 0.6× under |
| 372 | Plymouth Meeting | 2.6 pCi/L | 0.6× under |
| 373 | New Britain | 2.6 pCi/L | 0.6× under |
| 374 | Green Tree | 2.5 pCi/L | 0.6× under |
| 375 | Morton | 2.5 pCi/L | 0.6× under |
| 376 | Brackenridge | 2.5 pCi/L | 0.6× under |
| 377 | Fairless Hills | 2.5 pCi/L | 0.6× under |
| 378 | Woodbourne | 2.5 pCi/L | 0.6× under |
| 379 | Dresher | 2.5 pCi/L | 0.6× under |
| 380 | Hatboro | 2.5 pCi/L | 0.6× under |
| 381 | Springfield | 2.5 pCi/L | 0.6× under |
| 382 | Trevose | 2.5 pCi/L | 0.6× under |
| 383 | Dormont | 2.5 pCi/L | 0.6× under |
| 384 | South Greensburg | 2.5 pCi/L | 0.6× under |
| 385 | Verona | 2.5 pCi/L | 0.6× under |
| 386 | Exton | 2.5 pCi/L | 0.6× under |
| 387 | East Bangor | 2.5 pCi/L | 0.6× under |
| 388 | Old Forge | 2.5 pCi/L | 0.6× under |
| 389 | Telford | 2.5 pCi/L | 0.6× under |
| 390 | McGovern | 2.5 pCi/L | 0.6× under |
| 391 | Wyncote | 2.5 pCi/L | 0.6× under |
| 392 | Homestead | 2.5 pCi/L | 0.6× under |
| 393 | Park Forest Village | 2.4 pCi/L | 0.6× under |
| 394 | Audubon | 2.4 pCi/L | 0.6× under |
| 395 | Ebensburg | 2.4 pCi/L | 0.6× under |
| 396 | Fort Washington | 2.4 pCi/L | 0.6× under |
| 397 | Freemansburg | 2.4 pCi/L | 0.6× under |
| 398 | King of Prussia | 2.4 pCi/L | 0.6× under |
| 399 | Lima | 2.4 pCi/L | 0.6× under |
| 400 | Slippery Rock | 2.4 pCi/L | 0.6× under |
| 401 | Wyndmoor | 2.4 pCi/L | 0.6× under |
| 402 | Broomall | 2.4 pCi/L | 0.6× under |
| 403 | Waymart | 2.4 pCi/L | 0.6× under |
| 404 | East Washington | 2.4 pCi/L | 0.6× under |
| 405 | Quakertown | 2.4 pCi/L | 0.6× under |
| 406 | Bristol | 2.4 pCi/L | 0.6× under |
| 407 | Chesterbrook | 2.3 pCi/L | 0.6× under |
| 408 | Kenilworth | 2.3 pCi/L | 0.6× under |
| 409 | Evansburg | 2.3 pCi/L | 0.6× under |
| 410 | West Norriton | 2.3 pCi/L | 0.6× under |
| 411 | Warminster Heights | 2.3 pCi/L | 0.6× under |
| 412 | Trafford | 2.3 pCi/L | 0.6× under |
| 413 | Hulmeville | 2.3 pCi/L | 0.6× under |
| 414 | Irwin | 2.3 pCi/L | 0.6× under |
| 415 | Indian Mountain Lake | 2.3 pCi/L | 0.6× under |
| 416 | Orwigsburg | 2.2 pCi/L | 0.6× under |
| 417 | Dalton | 2.2 pCi/L | 0.6× under |
| 418 | Malvern | 2.2 pCi/L | 0.6× under |
| 419 | Maple Glen | 2.2 pCi/L | 0.6× under |
| 420 | Bloomfield | 2.2 pCi/L | 0.6× under |
| 421 | Fellsburg | 2.2 pCi/L | 0.6× under |
| 422 | Hawley | 2.2 pCi/L | 0.5× under |
| 423 | Limerick | 2.2 pCi/L | 0.5× under |
| 424 | Souderton | 2.2 pCi/L | 0.5× under |
| 425 | Woodside | 2.2 pCi/L | 0.5× under |
| 426 | Yardley | 2.2 pCi/L | 0.5× under |
| 427 | Emerald Lakes | 2.2 pCi/L | 0.5× under |
| 428 | Ivyland | 2.2 pCi/L | 0.5× under |
| 429 | Erie | 2.2 pCi/L | 0.5× under |
| 430 | Dupont | 2.1 pCi/L | 0.5× under |
| 431 | New Castle | 2.1 pCi/L | 0.5× under |
| 432 | Dublin | 2.1 pCi/L | 0.5× under |
| 433 | East York | 2.1 pCi/L | 0.5× under |
| 434 | Swarthmore | 2.1 pCi/L | 0.5× under |
| 435 | Stowe | 2.1 pCi/L | 0.5× under |
| 436 | Penn Wynne | 2.1 pCi/L | 0.5× under |
| 437 | Sunrise Lake | 2.1 pCi/L | 0.5× under |
| 438 | Bryn Athyn | 2.1 pCi/L | 0.5× under |
| 439 | Whitehall | 2.0 pCi/L | 0.5× under |
| 440 | Montgomeryville | 2.0 pCi/L | 0.5× under |
| 441 | Mount Oliver | 2.0 pCi/L | 0.5× under |
| 442 | Mount Lebanon | 2.0 pCi/L | 0.5× under |
| 443 | Meadowood | 2.0 pCi/L | 0.5× under |
| 444 | Chester Heights | 2.0 pCi/L | 0.5× under |
| 445 | Bedminster | 1.9 pCi/L | 0.5× under |
| 446 | Collegeville | 1.9 pCi/L | 0.5× under |
| 447 | Blue Bell | 1.9 pCi/L | 0.5× under |
| 448 | Pottstown | 1.9 pCi/L | 0.5× under |
| 449 | Rockledge | 1.9 pCi/L | 0.5× under |
| 450 | Bethel Park | 1.9 pCi/L | 0.5× under |
| 451 | Jacksonwald | 1.9 pCi/L | 0.5× under |
| 452 | Lampeter | 1.9 pCi/L | 0.5× under |
| 453 | Boothwyn | 1.9 pCi/L | 0.5× under |
| 454 | Village Green-Green Ridge | 1.9 pCi/L | 0.5× under |
| 455 | Harveys Lake | 1.9 pCi/L | 0.5× under |
| 456 | Blandon | 1.8 pCi/L | 0.5× under |
| 457 | Lansdale | 1.8 pCi/L | 0.5× under |
| 458 | Sellersville | 1.8 pCi/L | 0.5× under |
| 459 | West Newton | 1.8 pCi/L | 0.5× under |
| 460 | Jonestown | 1.8 pCi/L | 0.4× under |
| 461 | Mount Cobb | 1.8 pCi/L | 0.4× under |
| 462 | Oxford | 1.8 pCi/L | 0.4× under |
| 463 | Forest City | 1.8 pCi/L | 0.4× under |
| 464 | Lewisburg | 1.8 pCi/L | 0.4× under |
| 465 | Narberth | 1.8 pCi/L | 0.4× under |
| 466 | Perkasie | 1.8 pCi/L | 0.4× under |
| 467 | Levittown | 1.8 pCi/L | 0.4× under |
| 468 | Ligonier | 1.8 pCi/L | 0.4× under |
| 469 | Ardmore | 1.7 pCi/L | 0.4× under |
| 470 | Flourtown | 1.7 pCi/L | 0.4× under |
| 471 | Drexel Hill | 1.7 pCi/L | 0.4× under |
| 472 | Feasterville | 1.7 pCi/L | 0.4× under |
| 473 | Royersford | 1.7 pCi/L | 0.4× under |
| 474 | Castle Shannon | 1.7 pCi/L | 0.4× under |
| 475 | Fairchance | 1.7 pCi/L | 0.4× under |
| 476 | Heidelberg | 1.7 pCi/L | 0.4× under |
| 477 | Avonmore | 1.7 pCi/L | 0.4× under |
| 478 | Phoenixville | 1.7 pCi/L | 0.4× under |
| 479 | Eddington | 1.6 pCi/L | 0.4× under |
| 480 | Newtown | 1.6 pCi/L | 0.4× under |
| 481 | West Grove | 1.6 pCi/L | 0.4× under |
| 482 | Aspinwall | 1.6 pCi/L | 0.4× under |
| 483 | Willow Grove | 1.5 pCi/L | 0.4× under |
| 484 | McKees Rocks | 1.5 pCi/L | 0.4× under |
| 485 | Hermitage | 1.5 pCi/L | 0.4× under |
| 486 | Mount Pleasant | 1.5 pCi/L | 0.4× under |
| 487 | Bala-Cynwyd | 1.4 pCi/L | 0.4× under |
| 488 | Kennett Square | 1.4 pCi/L | 0.4× under |
| 489 | Northwest Harborcreek | 1.4 pCi/L | 0.4× under |
| 490 | Avondale | 1.4 pCi/L | 0.3× under |
| 491 | Norristown | 1.3 pCi/L | 0.3× under |
| 492 | Brookhaven | 1.3 pCi/L | 0.3× under |
| 493 | Topton | 1.3 pCi/L | 0.3× under |
| 494 | Ancient Oaks | 1.3 pCi/L | 0.3× under |
| 495 | Hughestown | 1.3 pCi/L | 0.3× under |
| 496 | Bridgeport | 1.2 pCi/L | 0.3× under |
| 497 | Millbourne | 1.2 pCi/L | 0.3× under |
| 498 | Newport | 1.2 pCi/L | 0.3× under |
| 499 | Philadelphia | 1.2 pCi/L | 0.3× under |
| 500 | Meadville | 1.1 pCi/L | 0.3× under |
| 501 | Mount Pocono | 1.1 pCi/L | 0.3× under |
| 502 | East Greenville | 1.1 pCi/L | 0.3× under |
| 503 | Birchwood Lakes | 1.0 pCi/L | 0.2× under |
| 504 | Cornwells Heights | 1.0 pCi/L | 0.2× under |
| 505 | Croydon | 0.9 pCi/L | 0.2× under |
| 506 | Bradford | 0.9 pCi/L | 0.2× under |
| 507 | Dunmore | 0.9 pCi/L | 0.2× under |