Noise Contour Lines
Noise contour lines are a continuous line on a map that represents equal levels of noise exposure.
Noise lessens from the innermost area within a contour line outward. Future noise contours lines may combine projected runway utilization percentages, fleet mix, flight corridors, and projected noise exposure including use of a planned additional parallel runways.
The least severe noise exposure occurs outside the 55 DNL contour line, the level at which the Federal Aviation Administration (FAA) describes noise exposure as minimal. The FAA considers residential development and other noise-sensitive land uses as acceptable in these areas and recommends no special noise-control measures.
Noise exposure is regarded as moderate between the 55 DNL and 65 DNL noise contours lines, and the FAA recommends that land-use controls be considered. Noise exposure is regarded as significant above the 65 DNL noise contour line and the FAA recommends that land-use controls be implemented.