An acoustic door is a door specially designed to block sound from passing from one room to the next when closed. These doors often contain a special seal along the edges which provides an additional level of sound insulation. The requirements on constructional sound insulation of door sets consisting of door blank, frame and sealings are classified into different types of use.

The sound insulation tests are performed in test facilities which are free of leakage, i. e. the sound is only transmitted by the door and not by other elements as walls, ceilings or gaps. 

The result is taken according to German Standard DIN 52210 in Rw = ‘sound insulation level in dB without sound transmission by flanking building components’. The sound insulation level measured on doors in the lab must be 5 dB higher (lead level) than the values required from the different applications in buildings.