A diagram illustrating airport noise contours around a runway, with color-coded flight paths showing arrivals (red) and departures (green). The oval-shaped noise contour lines extend along both ends of the runway centerline, with greater extent on the departure end.
Aerial photograph looking north over Seattle-Tacoma International Airport, showing the main terminal, gates with Alaska Airlines and other carrier aircraft, taxiways, and surrounding grounds. A red line is drawn on the image demarcating what appears to be a property or noise-contour boundary on an undeveloped grass area south of the airport perimeter road, adjacent to a light rail line and parking area.
2023-05-23
A Google Maps screenshot showing a blue polygon boundary drawn around Boston Logan International Airport (BOS) in East Boston, Massachusetts, extending over Boston Harbor toward Winthrop and Deer Island. The map includes visible labels for Boston Logan International Airport, surrounding neighborhoods, and landmarks such as Castle Island and Deer Island Light.
This is the Future (2018) Noise Exposure Map (NEM/NCP) for Seattle-Tacoma International Airport, produced as part of a 14 CFR Part 150 Study Update by the Port of Seattle. The map displays DNL noise contour bands (65–70, 70–75, and 75+ dBA) over surrounding communities including SeaTac, Des Moines, Normandy Park, Burien, and Tukwila, with a data table showing an estimated 9,712 residents and 3,771 housing units within the DNL 65+ dBA contour area of 7.3 square miles.
A GIS map comparing the old noise boundary (blue line) and new noise boundary (red line) around Seattle-Tacoma International Airport, with runway layout and airport symbol visible at center. Map data credited to Esri, HERE, DeLorme, Intermap, GEBCO, USGS, NPS, NRCAN, and other contributors.
2020-09-23
Currently, FAA law has extremely complicated rules for establishing a noise boundary around airports. (A noise boundary is a geographic area inside which there is a certain acceptable noise level.) This is referred to as the DNL65. and it has several major flaws. The FAA Reauthorization Act Of 2018 attempted to address these flaws in several ways. This letter, from a caucus of Congressmen engaged on airport community issues complains to the Administrator that the spirit of the law is not being adhered to and demands that he make attempts to put his agency into compliance.
The language is fairly technical, however there are a couple of basic points they raise: First, that the noise boundary be determined by actual noise measurements (currently the noise boundaries are 'modeled' and those calculations often do not reflect in any way the lived experience for residents.) Second, that the 'acceptable' noise level of sixty five decibels (hence DNL65) has been determined to be far too high to conform with current understandings of healthy living.
There is a geographic area around every large airport where, according to a formula developed by the Federal Aviation Administration (FAA), the ‘noise’ level is equal to or greater than 65 decibels DNL (Day Night Level). That area is depicted on a noise exposure map (NEM) and referred to as the Noise Boundary or just
2013-05-30
This exhibit from the Seattle-Tacoma International Airport 14 CFR Part 150 Noise Study compares the existing 2013 baseline noise exposure contours with projected 2018 baseline contours around Sea-Tac Airport. The data shows that the DNL 65+ dBA noise contour area is expected to shrink from 7.3 to 5.9 square miles, with affected housing units dropping from 3,771 to 1,887 and estimated population exposure falling from 9,712 to 4,879. Nine noise-sensitive facilities remain within the contour in both scenarios, and the maps illustrate how the impacted area covers portions of SeaTac, Burien, Des Moines, Tukwila, and unincorporated King County.
2011-01-01
Two aerial noise exposure contour maps for Seattle-Tacoma International Airport showing the 65 DNL boundary for 2013 (existing, in purple) and 2018 (future, in teal/green), with an outer study area boundary in orange. The contours extend over surrounding communities including Burien, SeaTac, Des Moines, Tukwila, and unincorporated King County.
Exhibit 1-1 from the Port of Seattle's Sea-Tac International Airport Noise Exposure Update, showing four panels of DNL (Ldn) noise contour maps at the 65, 70, and 75 dB levels for the years 1980, 1985, 1990, and 2000. The contours illustrate the projected lateral and longitudinal extent of aircraft noise impact around the airport's runway alignment over those two decades.
2023-05-23
2013-05-30
2011-01-01