14 C.F.R. § 150.9 Designation of noise systems.
Title 14 - Aeronautics and Space
For purposes of this part, the following designations apply: (a) The noise at an airport and surrounding areas covered by a noise exposure map must be measured in A-weighted sound pressure level (LA) in units of decibels (dBA) in accordance with the specifications and methods prescribed under appendix A of this part. (b) The exposure of individuals to noise resulting from the operation of an airport must be established in terms of yearly day-night average sound level (YDNL) calculated in accordance with the specifications and methods prescribed under appendix A of this part. (c) Uses of computer models to create noise contours must be in accordance with the criteria prescribed under appendix A of this part.
Title 14: Aeronautics and Space
PART 150—AIRPORT NOISE COMPATIBILITY PLANNING
Subpart A—General Provisions
§ 150.9 Designation of noise systems.
