Noise Levels in 91741, CA | Find Quiet Neighborhoods With Our Sound Map
51 dBA
Average noise across 91741
Quiet office
4,947
Residents above the EPA 55 dBA threshold
20% of 91741 residents
69 dBA
Loudest residential point
Highway traffic 50 ft away
This map shows modeled outdoor noise across 91741 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 4,947 91741 residents, or 20.4%, live above that level. By land area, 17.8% of 91741 is above 55 dBA.
82.2% below 55 dBA
17.8% above 55 dBA
See how noise in 91741 compares to similar-sized zip codes.
Noise by Part of 91741
Average noise levels for 91741 residents, grouped by direction from the center of 91741. The highest population-weighted average is in southeastern 91741; the lowest is in northern 91741, where just 5% of residents live in blocks above the EPA's 55 dBA threshold, a fifth of the share in the loudest section.
Southeastern 91741
53.6 dBA · Moderate-loud
Quiet office to normal conversation
Southwestern 91741
53.1 dBA · Moderate-loud
Quiet office to normal conversation
Central 91741
51.0 dBA · Moderate
Quiet office
Northeastern 91741
47.7 dBA · Mostly quiet
Quiet office
Northern 91741
45.8 dBA · Mostly quiet
Quiet suburban street at night
To the human ear, noise in southeastern 91741 sounds about 72% louder than in northern 91741, a 7.8 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 69 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.
At source
69 dBA
Highway traffic 50 ft away
165 ft
56 dBA
Normal conversation an arm’s length away
330 ft
49 dBA
Quiet office
660 ft
41 dBA
Quiet suburban street at night
¼ mile
35 dBA
Soft rainfall
½ mile
35 dBA
Soft rainfall
Calculated from the model's calibrated attenuation formula. About 10% of 91741 sits under tree canopy (lighter than most zip codes) and roughly 44% 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.
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Airport Noise
Ontario International (ONT) sits east of 91741. The U.S. Department of Transportation models aviation noise around this airport from federal traffic data, and the model uses those federal measurements rather than synthetic predictions.
Blocks under the approach and departure paths carry combined road-plus-aviation noise, with some exceeding 65 dBA on the map's Overall layer. Blocks on the opposite side of 91741, particularly to the west, show no measurable aviation contribution. Use the Aviation toggle on the map above to isolate the airport's footprint.
How Noise Is Distributed Across 91741
The bar chart below shows the share of 91741 residents in each noise band. About 85% of residents live below the EPA's 55 dBA threshold, and roughly 0% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.
How 91741 Compares
91741 sits the lowest among the peer group. Below: how 91741's average outdoor noise and share of residents above the EPA threshold compare with 91740, 91724, 91010, and 91750.
Average noise level (dBA)
91741's 51.0 dBA pop-weighted average is the lowest among the peer group. California as a whole averages 54.0 dBA and the U.S. averages 52.0 dBA. Both are lower than 91741 because most of either area is rural land away from major roads.
Share of residents above 55 dBA
About 20.4% of 91741 residents live in blocks where outdoor levels exceed the EPA's 55 dBA threshold. That's fewer than any of its peer group. Measured by land area instead, 17.8% of 91741's footprint sits above 55 dBA, against a California average of 36.0% and a national average of 28.1%.
What This Means if You're Moving to 91741
- Distance from highways matters more than the neighborhood name. Two homes in the same zip code can differ by 20 dBA if one sits 100 meters from and the other 500 meters away. The model captures this at 100-meter resolution, so noise exposure changes block by block.
- Tree canopy can help reduce modeled noise exposure. Roughly 10% of 91741 is under tree cover (lighter than most zip codes), and the dominant land cover is medium-intensity developed land. Both are measured from federal USDA Forest Service and USGS satellite imagery at 30-meter resolution. Streets with 60% or higher canopy show 3 to 5 dBA lower noise than comparable streets with bare ground or pavement, which is why the per-place decay rate above already accounts for it.
- Airport noise is directional. Ontario International's approach paths concentrate aviation noise to the east. Neighborhoods to the west of downtown show no measurable contribution from the airport.
