The current low-frequency noise problems: Zhejiang University Institute of Environmental Pollution Control Technology in the typical residential areas of Hangzhou on supporting equipment noise sources with acoustic instruments for testing and analysis, selected power supply systems, underground garages, elevator equipment, heating systems, drainage and water supply systems, air-conditioning equipment, ventilation equipment, noise sources, the results show that the 12 kinds of typical noise sources of the 9 kinds of maximum sound pressure level is located in the frequency band is the most in the low-frequency band. As a result, low-frequency noise has become the most influential noise source in residential areas.

At present, there are more and more complaints about low-frequency noise in the environmental noise from the residents of urban residential areas, and the current environmental noise standard in China has no standard for low-frequency noise. So in the measurement of low-frequency noise in urban residential areas, the decibel display of the sound level meter tends to comply with the current relevant noise standards, and does not exceed the standard.GB 22337-2008 "Social Life Environmental Noise Emission Standard", GB 12348-2008 "Industrial Enterprise Factory Noise Emission Standard" and other measurement methods are A sound level of the sound level meter is used to measure and evaluate the environmental noise.

Because the frequency characteristic curve of A meter is a substantial attenuation of the low and high frequency bands of the noise, and there is no attenuation of the middle frequency band. Its frequency characteristic curve is like the bottom of a pot with an inverted lid, high in the center and low at both ends. Therefore, when measuring low-frequency noise with A sound level, the sound level of the low-frequency noise has been greatly attenuated, and the meter does not show it. It must be measured with linear or C sound level to truly and objectively reflect the existence of low-frequency noise, but the current national environmental noise measurement method does not use linear or C sound level to measure environmental noise. This is a deficiency in national environmental noise standards and measurement methods. It is understood that the state is brewing the development of environmental standards and measurement methods for low-frequency noise.

Through the above investigation and demonstration of urban low-frequency noise is indeed a greater danger to human health, the city at all levels of environmental protection departments, health departments, urban design and planning departments, transportation departments, real estate developers should pay close attention to, should be effectively implemented, "the spirit of people-oriented," as soon as possible to develop the relevant environmental standards for low-frequency noise. Low-frequency noise related environmental standards should be formulated as soon as possible. Attention to the city's acoustic environmental protection work, in all aspects of the strengthening of protective measures to protect women and children, to protect the city residents, to protect the health of enterprise workers.