Global Noise Level Indicator - Air

Indicates noise levels induced by air transport Mapping represents isophone curves plotted in increments of 5dB(A) from 55dB(A) The Lden (Day Evening Night) is the indicator of the average sound level for the whole day of 24 hours. It is calculated by calculating over the year the noises recorded at the different periods of the day, to which a weighting is applied for the more sensitive periods (+5dB(A) in the evening and +10 dB(A) at night). It is therefore not a real or measured noise level, but a weighted indication. The entry was made for a cartographic restitution scale of 1/10,000th. The cards will be updated every 5 years.