Decibel (dB)

The noise level is expressed in dB.
If we try to express noise levels on a linear scale, the smallest noise level that humans can hear is 1, and the maximum level that we can tolerate is a huge number, 5,000,000, which is difficult to handle. In contrast, noise (sound pressure level), expressed in decibels, is

Sound pressure level = 20log P/P0

P = Actual sound pressure
P0 = Minimum value of sound pressure that can be heard by humans

This means that the human audible sound pressure range can be expressed in the range of 0 to 130 dB, making it easier to express.