the third and fourth floors of restaurant smoke exhaust downstairs will be affected. The standard noise of civil range hoods in China should not exceed 65-68dB, and the high-power range hoods in hotels should not exceed the industry standard. Generally, the noise spread of range hoods is only three or four floors. Catering, also known as catering industry, is a food production and operation industry that provides consumers with all kinds of drinks, food, consumption places and facilities through instant processing, commercial sales and service labor.