Noise protection refers to measures that reduce the transmission of sound from a sound source to a receiver. The primary purpose of suitable measures (e.g. elastic surfaces, mass, separation of components) is to avoid or reduce the transmission of sound.
Sound propagates in mechanical vibrations and pressure waves. The sound vibrations audible by humans are in the frequency range from 20 to 20,000 Hz. The frequency range of 200 to 5,000 Hz is of particular importance for sound insulation, as this range is perceived particularly clearly by the human ear. Sound pressure is perceived from a hearing threshold of 10 dB(A) and is perceived as pain from a threshold of 100 dB(B). If transmitter and receiver are in the same room, sound is reduced by sound absorption. In addition to the air present in the room, the quality of the floor covering, and furnishings play a particularly important role. Structural sound insulation is possible if transmitter and receiver are spatially separated.
