five meters. According to the query Sohu. com. The noise value of the hotel exhaust fan should not exceed 51 to 55 decibels, and it is illegal to exceed 55 decibels. Therefore, the noise of the hotel exhaust fan can be broadcast at most 5 meters. The standard usage of noise is noise. From the physiological point of view, any sound that interferes with people's rest, study and work and the sound that people want to listen to, that is, unnecessary sound, is collectively called noise.