Xiamen hongfashengdian co., LTD., an automobiles electronics factory, suffers from serious noise pollution, with numerous outdoor equipment and relatively dispersed noise pollution sources, especially the air compressor room on the first floor and the wind machine room on the roof. When these devices are in operation, they produce great noise, which seriously affects the living environment of surrounding residents.

The air compressor room on the first floor is equipped with intake and exhaust mufflers and sound isolation doors to meet the requirements of air compressor unit for noise reduction and ventilation and heat dissipation. The roof fan is equipped with sound insulation hood and ventilation muffler to meet the requirements of noise insulation and ventilation and heat dissipation of the fan. Noise control governance after the factory bound near the residential area outside the red line 1 meters, to meet the emission of environmental noise within the boundary of industrial enterprises "the Ⅱ GB12348-2008 standard. Namely, daytime ≤60dB(A) and night ≤50dB(A).