EPNdB
EPNdB, or Effective Perceived Noise level in decibels, is a measure of the relative loudness of an aircraft pass-by event. It is defined in Annex 16[1][2] of the ICAO International Convention on Civil Aviation, and in the US Federal Air Regulations Part 36.[3]
The EPNdB rating of an aircraft is used to estimate how much contribution a given aircraft will make to the noise impact of an airport in a community, which is estimated using the day-night average sound level metric.
Detailed information on measurement of aircraft acoustic signature to meet the requirements of Annex 16 is found in ICAO Document 9501[4] and IEC 61265.[5] Data acquisition in one-third-octave bands is required, followed by processing to yield a logarithmically-scaled value in decibels relative to a sound pressure of 20 micropascals, approximately the threshold of hearing.
References
- ↑ https://www.caa.govt.nz/ICAO/Annex_16_Vol_I.pdf
- ↑ http://www.icao.int/Meetings/EnvironmentalWorkshops/Documents/NoiseCertificationWorkshop-2004/BIP_2_2_jb.pdf
- ↑ http://www.ecfr.gov/cgi-bin/text-idx?rgn=div5&node=14:1.0.1.3.19
- ↑ http://www.icao.int/environmental-protection/Documents/Publications/Doc_9501_Volume_I.pdf
- ↑ https://webstore.iec.ch/publication/5076