This map shows modeled outdoor noise across Nantucket County at 100-meter resolution, combining road, aviation, and rail sources. Green areas measure below 45 dBA. Orange and red exceed the EPA's 55 dBA outdoor threshold linked to long-term health effects. Use the layer toggles to view each source on its own or all together.
What the numbers sound like
- 30 dBAWhisper
- 40 dBASoft rainfall
- 45 dBAQuiet suburban street at night
- 50 dBAQuiet office
- 55 dBAEPA outdoor threshold: light traffic 100 ft away
- 60 dBANormal conversation an arm's length away
- 65 dBABusy restaurant
- 70 dBAHighway traffic 50 ft away
- 80 dBACity bus interior
Population Above the EPA Outdoor Threshold
The EPA's 55 dBA outdoor reference level is a common benchmark for residential noise exposure, especially for activity interference, annoyance, and long-term community noise concerns. About 4,033 Nantucket County residents, or 30.2%, live above that level. By land area, 34.7% of Nantucket County is above 55 dBA.
See how noise in Nantucket County compares to similar-sized counties.
Noise by Part of Nantucket County
Average noise levels for Nantucket County residents, grouped by direction from the center of Nantucket County. The highest population-weighted average is in eastern Nantucket County; the lowest is in northeastern Nantucket County, where just 6% of residents live in blocks above the EPA's 55 dBA threshold, a third of the share in the loudest section.
Eastern Nantucket County
25% of people above 55 dBA
Central Nantucket County
34% of people above 55 dBA
Northwestern Nantucket County
29% of people above 55 dBA
Southwestern Nantucket County
17% of people above 55 dBA
Northeastern Nantucket County
6% of people above 55 dBA
To the human ear, noise in eastern Nantucket County sounds about 87% louder than in northeastern Nantucket County, a 9.0 dBA gap. Every 10 dBA roughly doubles perceived loudness. Within any of these directions, two homes a quarter mile apart can still differ by 10 or more dBA depending on how close they sit to a major highway.
How far back from do you need to be?
produces an estimated 85 dBA at its loudest centerline points. Noise drops logarithmically with distance, with the exact rate depending on what's between you and the road. Tree cover, walls, terrain, and pavement type all matter. At roughly a quarter mile back, traffic fades into the noise level of a quiet office.
Calculated from the model's calibrated attenuation formula. About 24% of Nantucket County sits under tree canopy (about average for counties) and roughly 27% is impervious surface like pavement and rooftops. Both are folded into the per-place decay rate above. Heavier canopy pulls noise down faster with distance; impervious surfaces slow the drop.