How to control low frequency noise?
In general, the sound frequency is between 125-250 Hz, and the sound waves in the ear are relatively comfortable. The frequency of the low-frequency noise is below 500Hz (octave), which exceeds the peak point of the human ear's comfortable reception, which will cause continuous low-frequency noise to harass people. The main sources of low frequency noise in the city are: elevators, transformers, central air conditioning (including cooling towers) and traffic noise. Low-frequency noise has a strong penetrating power for the building, and its “moisture force†will bring “injury†to the listener. However, because the decibel of this sound is not high, it does not violate the test standards. The management of low frequency noise is one of the recognized challenges in the field of noise management. In general, there are three main methods for controlling noise, including controlling the noise source, protecting the transmitted person, and cutting off the transmission route. If the soundproof window is installed, it is a way to protect the person being spread, or it can be understood as cutting off the transmission route. Another more positive way is to control from the noise source. For example, in the elevator car, substation, spray water-based damping paint to control. Nanchang Jialu Environmental Protection has become more and more serious for the influence of low-frequency noise on residents. Various solutions have been designed. In the face of different low-frequency noise control problems, targeted solutions can be proposed. The local low-frequency noise control effect is more obvious. If there is cooperation with low frequency noise.
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