This standard specifies the limits of railway noise at urban railway boundaries and its measurement methods. This standard applies to the evaluation of urban railway boundary noise. GB 12525-1990 Railway boundary noise limits and measurement methods GB12525-1990 Standard download and decompression password: www.bzxz.net

National Standards of the People's Republic of China
Emision standards and measurement methods of railway noise on the boundary alongside railway line Subject content and scope of application
This standard specifies the urban railway boundary Limits for railway noise and methods of measurement. This standard applies to the evaluation of urban railway boundary noise. 2' Reference standardswwW.bzxz.Net
GB3785 Electrical and acoustic performance and measurement methods of sound level meters GB3222 Measurement methods of urban environmental noise
3 Terminology
3.1 · Railway noise railway noise||tt| |Refers to the noise produced by rolling stock during operation. 3. 2 Railway boundary alongside railway line refers to the point 30m away from the center line of the outer track of the railway. 3.3 Background noise background noise refers to the environmental noise at the measurement point when no locomotive vehicles pass by. The railway boundary noise limit
Table 1
Equivalent sound level L [dB(A))||tt ||Daytime
Night
70
70
Note: The daytime and nighttime hours in this limit are determined by the local people's government according to local customs and seasonal changes. Certainly. 5 Measurement method
5.1 In principle, the measurement point is selected at the railway boundary 1.2m above the ground and not less than 1m away from the reflector. 5.2 Measurement conditions
GB 12525-90
5.2.1 Measuring instrument: It should comply with the integrating sound level meter of Type II or Type I or above specified in GB3785 or other measuring instruments of the same accuracy. Use "fast gear" when measuring, and the sampling interval should not be greater than 1s. 5.2.2 Meteorological conditions: It should comply with the meteorological conditions specified in GB3222, and the measurement should be carried out in weather without rain or snow. The instrument should be equipped with a wind cover, and measurements should be stopped when the wind is above Level 4.
5.3 Measurement content and measured values
National Environmental Protection Administration approved on 1990-11-09 for implementation on 1991-03-01
GB1252590
5.3.1 Measurement time: day and night , and night are selected at an hour close to the average density of rolling stock operation, and are used to represent daytime and nighttime respectively. If necessary, conduct full-time measurements between stacks or at night. 5.3.2 Use an integrating sound level meter (or other measuring instrument with the same function) to read the equivalent sound level (A) for 1 hour: dB. 5.4: The background noise should be more than 10dB(A) lower than the railway noise. If the difference in sound level between the two is less than 10dB(A), correct it according to Table 2. Table 2
Difference value
Correction value
6 Measurement report
The measurement report should include the following content:
e.
b.
d.
e.
Measuring instruments;
3
-3
4～5
12| |tt||6～9
dB
Measurement environment (relative height II between the measuring point and the track surface, several lines, ground conditions between the measuring point and the track, such as land, grass, etc.) ;Traffic flow density (number of passing rolling stock per hour): background noise level;
equivalent sound level in 1 h.
Number
Several lines
Ground conditions between the measuring point and the track
Measuring point instrument
Equivalent sound level
Background noise Sound level
Additional instructions:
GB 12525--90
Appendix A
Measurement record sheet
(reference)
Railway Boundary noise measurement record sheet
Location
Traffic density
dB(A)
dB(A)
This standard is proposed by the National Environmental Protection Administration. The main drafters of this standard are Zheng Tianen, Wang Side, He Qingci, and Li Xiuping. This standard is interpreted by the National Environmental Protection Administration. hour
minute to
year
hour
distance from track surface
m
month
minute||tt ||Measuring person
Day
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