Reverberation time is the time in seconds that it takes the sound level to drop by 60 dB after a sound source has ceased. The reverberation time can be measured using Sabine’s Formula: T = (V x 0.16)/A
T = Reverberation time / V = Room volume / A = Absorption area
The absorption area is a room’s total sound-absorption quantity expressed in m2.
The sound pressure level, e.g. how much noise is transmitted from one room to another, is measured in decibels (dB). dB levels measured can be plotted on a Hz graph from 31.5 Hz to 16,000 Hz.
The human ear cannot capture all frequencies equally well, thus the A‑weighted sound pressure level dbA is often used.
Floor-impact noise and its attenuation is measured in dB. The level of floor‑impact noise should be as low as possible.
Measurement of floor-impact sound is usually from 100 Hz to 3150 Hz. Several noise scenarios can apply with regard to floor coverings. Flank transmission is when airborne sound insulation is reduced in the event of a partition wall between two rooms.
Parquet-floor resonance occurs in the event of a reduction in airborne-sound insulation between parquet flooring and parquet underlay. Drumming sounds can also occur, usually with hard floor coverings.
Sound waves can be described in the following terms:
Frequency – waves passing a point every second and measured every second in Hz.
Wavelength – distance between wave peaks
Amplitude – a measure of wave size
Structure-borne noise occurs when a sound source creates fluctuations and vibrations in a given structure