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.
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.