Air & Transportation

Environmental Quality Standards for Aircraft Noise

Latest Amendment by Environment Agency
Notification No. 91 of 1993

In accordance with the provisions of Article 16 of the Basic Environment Law (Law No. 91 of 1993), the environmental conditions relating to aircraft noise standards are notified as follows.
The standards for regulating the environmental conditions of aircraft noise (hereinafter referred to as "environmental quality standards") are established as follows according to Article 9 of the Basic Law for Environmental Pollution Control and the target dates thereof. The maintenance of the standards is desirable to preserve the living environment and to contribute to protecting people's health.

I. Environmental Quality Standards

1. The values of the environmental quality standards are established for each category of area shown in Table 1. Prefectural governors shall designate the category of area.

Table 1.

Category of areaStandard value (in WECPNL)
70 or less
75 or less
Area category I refer to areas used exclusively for residential purpose and Area category II refers to other areas where the normal living conditions shall be preserved.

2. The values of the environmental quality standards referred in Paragraph 1 above are measured and evaluated by the following method.

(1) Peak levels of aircraft noise, which is higher than background noise level by 10 dB or more, and the number of such aircraft, shall be recorded in dB (A) for, in principle, for seven consecutive days.

(2) Measurements shall be carried out outdoors and at points selected as representing the points of aircraft noise in the area concerned.

(3) The timing of measurements shall be chosen as representing the duration of aircraft noise at the point of measurements, taking into consideration the flight conditions and meteorological conditions including wind directions.

(4) The aircraft noise shall be evaluated as follows. The WECPNL values for each day will be calculated from peak levels of aircraft noise and numbers recorded under subparagraph (1) using the following equation. The energy mean of daily WECPNL values is used to calculate the noise level in question.

WECPNL = dB(A) + 10log10N - 27

dB(A) stands for the energy mean of all peak levels of any one day, and N stands for a value calculated by the following equation: N = N2 + 3N3 + 10(N1 + N4), where N1 is the number of aircraft between 0:00 a.m. and 7:00 a.m., N2 the number between 7:00 a.m. and 7:00 p.m., N3 the number between 7:00 p.m. and 10:00 p.m., and N4 the number between 10:00 p.m. and 12:00 p.m.

(5) Anyone of the following instruments can be used for measurement: the sound level meter provided for in Japan Industrial Standards C-1502, precision sound level meter under International Electric Standards Conference Pub/179, or any other equivalent instrument. In these cases, A-weighted calibration and slow dynamic response shall be used.

3. The environmental quality standards shall not be applied to areas around airports where there are 10 or less daily landings and take-offs and to those around airports in remote islands.

II. Target Dates

1. In areas around public airports and others, the environmental quality standards shall be attained and maintained by the target dates specified for each category of airports shown in Table 2. In these cases, in the areas where the target dates are more than five years away, the improvement goals in Table 2 shall be attained as an interim measure in order to facilitate the attainment of the environmental quality standards step by step.

2. In areas around airports used by the Self Defense Forces, etc., efforts shall be made to attain and maintain the environmental quality standards by the same target dates as those for the public airports under similar conditions in Table 2, while considering the average number of landings and take-offs, type of aircraft, and concentration of houses.

3. In areas where it is deemed difficult to attain the environmental quality standards by the target dates in spite of the comprehensive measures to be taken to control aircraft noise, measures shall be taken, including sound-proofing the houses of people wishing to remain in the area, with a view to obtaining the indoor conditions equivalent to the ones where the environmental quality standards are being met. At the same time, maximum endeavors shall be made to attain the environmental quality standards as soon as possible.

Table 2

Airport CategoriesTarget DatesImprovement Goals
Airport to be built in future Immediately ----
Existing Airport Third class and equivalent airports Immediately ----
Second-class airports except Fukuoka Airport (A) Within five years ----
d.o. (B) Within ten years Within five years to attain less than 85 WECPNL (or 65 WECPNL or less indoors, in areas exceeding 85 WECPNL)
New Tokyo International Airport d.o. d.o.
First class airports (excepting New Tokyo International Airport) and Fukuoka Airport As soon as possible within ten years or more 1. Within five years to attain less than 85 WECPNL (or 65 WECPNL or less indoors in areas exceeding 85 WECPNL)
2. Within ten years to attain less than 75 WECPNL (or 60 WECPNL or less indoors in areas exceeding 75 WECPNL)
  1. "Existing" airports are those existing on the date of establishment of the environmental quality standards.
  2. Airports of category B of second class are those where there are regular commercial landings and take-offs of aircraft's equipped with turbo-jet engines, and category A means the others.
  3. The dates indicated in Table 2 are to be counted from the date of establishment of the environmental quality standards.