China’s “health standard for noise of industrial enterprises” stipulates that the allowable value of noise in production workshops and workplaces of industrial enterprises is 85dB (a). 1f the existing industrial enterprises can not reach the standard temporarily after efforts, it can be relaxed appropriately, but it shall not exceed 90dB (a)
technical measures should be taken to control noise from three aspects: sound source, sound transmission way and human ear< First, controlling and eliminating noise sources is a fundamental measure. Through the process reform, the equipment and process that produce noiseless or low sound are used to replace the high sound equipment, such as welding instead of riveting, hydraulic instead of forging, shuttleless loom instead of shuttle loom, etc; Strengthen machine maintenance or reduce unnecessary parts, eliminate the noise caused by machine friction, collision, etc; For example, rubber liner is used instead of steel plate in ball mill, rubber liner or copper manganese alloy is added at mechanical impact point, and rolled parts can fall into pool instead of falling to the ground secondly, plant planning and plant design should be carried out reasonably. There should be a certain distance or protective belt between the workshop with strong noise and the non noise workshop and the residential area; The windows of noise workshop should be designed at 90 degree with non noise workshop and residential area; The noise sources should be concentrated and sound insulation measures should be taken in the noise workshop as far as possible. Sound absorbing materials should be installed indoors, and sound absorbing materials should be installed or smeared on the wall surface to reduce the reflected noise in the workshop thirdly, anti noise measures should be taken for local noise sources. Noise elimination device is used to isolate and seal the noise source; The vibration isolation device is used to prevent the noise from spreading through the solid; Epoxy resin is used to fill the gap between rotor slot and stator to reduce electromagnetic noise< Fourth, control the propagation and reflection of noise(1) sound absorption: porous materials such as glass wool, slag cotton, foam plastic, felt cotton wool, etc., are decorated on indoor walls or suspended in space or made into sound absorbing screens; 2) Noise elimination: the use of muffler to reduce aerodynamic noise, such as a variety of fans, air compressors, such as engine intake, exhaust noise(3) Noise: use certain materials, structures and devices to seal the noise source, such as sound insulation wall, sound insulation room, sound insulation cover, sound insulation door, window and floor(4) Damping, vibration isolation and noise elimination: damping is to apply asphalt, paint, etc. on the wall of the air duct to reduce the vibration of the wall; Vibration isolation is to install damping devices and anti vibration structures on the foundation, floor and wall of noise source. Such as installing anti vibration rubber pad on the forging hammer base, filling sand in the pipe of the column, etc fifthly, personal protection. Due to technical or economic reasons, workers in posts with noise exceeding the national health standards usually wear earplugs, earmuffs or helmets to protect their hearing< Sixth, workers exposed to noise should be given regular hearing and physical examination. 1f persistent hearing loss in high frequency band is found and exceeds the normal fluctuation range, the workers should be transferred from the noise work position as soon as possible. During the physical examination before employment, those with sensorineural deafness and obvious organic diseases of cardiovascular and nervous system should not take part in the rest room with noise; Shorten the working time in high noise environment as far as possible; Regularly monitor the noise in the workshop, and supervise the factories, mines and workshops with serious noise hazards, so as to promote them to take active measures to reduce the noise to meet the requirements of noise health standards copyright notice: This article is reproduced by 1nternet media, only representing the author’s point of view, and has nothing to do with this website. 1f the information column articles and comments violate your legal rights, please call to let us know and we will deal with them in time