Clean room noise detection mainly considers the impact of clean room environmental noise on people. Understand the basic concept and expression method of clean room noise detection, familiar with the working principle, structure composition and technical parameters of noise detection instrument, master the determination of noise detection point, instrument installation and operation process.
Clean room noise detection
Sound is produced by the vibration of objects. It is a change in air pressure that can affect the human ear and brain. This change transmits energy from natural or man-made sources of vibration (such as mechanical operation, vocal cord vibration during speech, etc.).
The vibrating object that radiates sound is called "sound source", and the sound source can be transmitted to the human ear only after sounding through a certain medium. The earliest human perception of sound is through the ear, and the sound that ordinary people can hear has an exact range of data, which is called "threshold". The minimum level of sound that the average ear can pick up is called the "audible threshold", with a sound intensity of about 10-12W/m2, which the average ear can tolerate!
When the area of the room is not more than 50m2, only one point in the center of the room is measured. When the room area is large, add a measuring point for each increase of 50m2. The measuring point is 1.0m above the ground. When the conditions are available, it is advisable to measure the noise and background noise of the room at static working conditions.
According to the requirements of clean room design code, the noise of non-unidirectional flow clean room should not be greater than 60dB(A) in the empty state of clean room. Unidirectional flow and mixed flow clean room noise should not be greater than 65 dB(A).
The formulation of clean room noise standard mainly considers the annoyance effect of noise, the interference of language communication and the influence on work efficiency. Domestic studies on the impact of noise on health show that general industrial noise lower than 80dB (A) has little impact on health.
After the clean room is completed, before it is put into use, it must first be tested by the state-authorized testing institution, and obtain the qualified report of the clean room test, and then thoroughly disinfected before it can be used normally.