The noise reduction effect is expressed by the noise reduction amplitude and the noise reduction depth. dB is a ratio, a numerical value, and a pure counting method without any unit marking. According to national regulations, the noise standard in residential areas is below 50 decibels during the day and below 40 decibels at night.
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Here is another set of data to help you understand the concept of 26db. 10db is about when people can just feel the sound. Generally speaking, when the self-voice is around 30db, it will not affect normal life and rest, but when it reaches 50db or more, people have a greater feeling. Difficult to fall asleep. 10~20db is very quiet and hardly feel; 20~40db is equivalent to speaking softly; 40~60db is equivalent to ordinary indoor conversation; 60~70db is equivalent to shouting loudly, which is detrimental to nerves; 70~90db is very noisy, and staying in this way for a long time Studying and living in an environment will gradually destroy human nerve cells; 90~100db can cause hearing loss; 100~120db is unbearable, and deafness can be temporarily suppressed in a few minutes.
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