1, outdoor standard
Scope of application of various standards:
Level 0 standard is suitable for areas that need to be quiet, such as convalescent areas, senior villa areas, senior hotel areas, etc. Located in the suburbs and rural areas, such areas shall be implemented according to the standard of 5 decibels stricter than Class 0.
1 class standard is applicable to areas where residential, cultural and educational institutions are the main ones. Rural living environment can be implemented with reference to such standards.
Level 2 standard is applicable to residential, commercial and industrial mixed areas.
Level 3 standards are applicable to industrial areas.
The four-level standard is applicable to inland waterways on both sides of urban road traffic trunk lines and across urban areas. This kind of standard is also applicable to the limits of background noise (which refers to the noise level of outdated trains) on both sides of the main and secondary lines of railways passing through cities.
2. Indoor standards:
Indoor noise standards can be divided into residential and non-residential types. The indoor noise standard of residence is formulated according to the requirements of quiet life and the environmental noise standard of the region, with reference to the window conditions of residence, and generally should not be lower than the environmental noise standard of the region by 20 decibels.
The indoor standard of residential buildings in China is lower than the environmental noise standard 10 dB, because there are many small factories close to residential buildings in China. The indoor noise standard for non-residential houses is stipulated according to the purpose of the room.
Second, the detection method:
The comprehensive average sound level meter or environmental noise automatic monitoring instrument with accuracy of Class 2 or above shall meet the requirements of GB3785 and GB/T 17 18 1, and shall be verified regularly. Before and after measurement, the indication deviation of measuring instruments calibrated by acoustic calibrator shall not be greater than 0.5 dB, otherwise the measurement will be invalid. The acoustic calibrator shall meet the requirements of GB/T 15 173 for 1 or 2 acoustic calibrators. When measuring, the microphone should be equipped with a windshield.
According to the monitoring object and purpose, the following three measuring point conditions (referring to the position of the microphone) can be selected to measure the environmental noise:
1, generally outdoors
Measured at least 3.5 m away from any reflector (except the ground), the height from the ground is1.2 m. If necessary, it can be placed on a high-rise building to expand the sound monitoring range. When measuring with a monitoring vehicle, the microphone should be fixed at the height of 1.2m at the top of the vehicle.
2. Outdoor in noise-sensitive buildings
Outside noise-sensitive structures, the distance from the wall or window 1 m, and the height from the ground1.2m.
3. Indoor noise-sensitive structures
At least 1 m from the wall and other reflecting surfaces, about 1.5 m from the window, and 1.2 m to 1.5 m from the ground.
Extended data:
Some noise control methods:
1. To reduce the noise of sound source, industry and transportation industry can choose low-noise production equipment and improve production technology, or change the motion mode of noise source (such as reducing the vibration of solid sound generator through damping and vibration isolation).
2. Reduce noise, control noise propagation, change the noise propagation path that has been emitted by the sound source, such as taking measures such as sound absorption, sound insulation, sound barrier and vibration isolation, and rationally plan the layout of cities and buildings.
3. When the noise protection of the receiver or the receiver fails to take measures in terms of sound source and transmission route, or the acoustic measures still fail to achieve the expected effect, protective measures must be taken for the receiver or the receiver. For example, workers who have been exposed to occupational noise for a long time can wear ear protection products such as soundproof earplugs, earmuffs or helmets.
Baidu Encyclopedia-Environmental Noise Standard