This map shows modeled outdoor noise across 40th and A 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 86 40th and A residents, or 2.2%, live above that level. By land area, 2.4% of 40th and A is above 55 dBA.
See how noise in 40th and A compares to similar-sized neighborhoods.
Noise by Part of 40th and A
Average noise levels for 40th and A residents, grouped by direction from the center of 40th and A. Southern 40th and A carries the highest population-weighted average; Central 40th and A carries the lowest. Just 0% of residents in Central 40th and A live in blocks above the EPA's 55 dBA threshold, a fifth of the share in Southern 40th and A.
Central 40th and A
0% of people above 55 dBA
Eastern 40th and A
0% of people above 55 dBA
Northern 40th and A
0% of people above 55 dBA
Southern 40th and A
4% of people above 55 dBA
Western 40th and A
6% of people above 55 dBA
Southern 40th and A sounds about 23% louder than Central 40th and A to the human ear, a 3.0 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 59 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 soft rainfall.
Calculated from the model's calibrated attenuation formula. About 23% of 40th and A sits under tree canopy (heavier than most neighborhoods) and roughly 39% 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.