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4 Posts in this encyclopedia categoryImpact/footstep sound
Footstep sound is a type of solid-borne impact sound caused by people walking about on hard surfaces. Dedicated impact sound insulation materials (foams, non-wovens) can be used to minimize such sounds.
Impedance tube
An impedance tube serves for the measurement of a material's absorption coefficient and reflection rate in case of perpendicular sound incidence.
Impulse noise
Impulses are short sound events with sharply rising intensity. At workplaces that are subject to impulse noise, the sound pressure level must not exceed 140 dB.
Infrasound
Infrasound is air-borne sound with a frequency below 20 Hz. As the human ear cannot hear sounds with such low frequencies, infrasound with a low sound pressure level cannot be perceived by humans.