Can the human ear hear sound when the noise level is 0 dB?
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This post was last edited by Hansonwen on 2018-8-24 at 15:10. While reviewing the manual on noise control design for process systems today, I suddenly wondered: can a person hear sound when the noise level is 0 dB(A)? Why? Put another way, if the noise level measured when a device is in operation is 0 dB(A), can we actually hear the sound produced by that device?
0 decibels means complete silence. You can hear a needle falling to the ground.
Let me put it another way: if the noise level measured when a device is in operation is 0 dB, then can human ears actually hear the sound produced by that device while it is running?
Where is there a requirement that equipment must operate at 0 decibels? If it’s not running, it’s 0 decibels. It runs, energy is generated as well as energy is consumed; these cannot be equated. Some of that energy is released in other ways, one of which is sound. Can it be understood this way?
A professional soundproof room in South Minneapolis, USA – completely silent; being inside it would drive one crazy
Hahaha, it really would drive one crazy. But 0 decibels is a unit for sound intensity level; it does not mean complete silence. Even at 0 decibels, sounds can still be heard :P
0 decibels is the weakest sound that a human can hear, that is, the lower limit of human hearing.
The lowest sound pressure that humans can hear is 0 dB. The logarithm of the ratio between the detected sound pressure and this lowest audible sound pressure is what is expressed in decibels. △=20lg(P2/P1) dB. P2 and P1 represent the sound pressures of two different signals; if P2 is twice as large as P1, the difference in decibels between the two signals is 6 dB
It depends on the environment; 0dB represents the weakest sound level, indicating that it’s still possible to hear it, but due to the influence of the environment, it’s likely impossible to hear it. The environment is uncontrollable, right?