Airborne sound insulation

Airborne sound insulation, also simply called sound insulation, is required when a shield needs to be in place against sources of noise coming from other rooms, e.g. at workplaces. It is understood to be the prevention or reduction of sound penetrating through a separation plane.

The sound waves are primarily reflected with the result that the sound level in the sending room increases. To counteract this effect, composites made of sound insulating and absorbing materials are often used. Sound insulation is achieved by increasing the mass per unit area, e.g. of sheet metals, using flexible insulation mats. Airborne sound insulation is dependent on frequency; the lower the frequency, the higher the mass per unit area must be.

The effectiveness of airborne sound insulation is indicated by the sound insulation factor R, the difference of sound level in dB in front of and behind the separation plane.