scope:

The purpose of this Guideline is to impart the important knowledge concerning the correct application of sound regulations in the planning, design and laying of pipes with mostly round cross-section in industrial plants; it is broken down according to the criteria generation of sound, sound transmission, sound radiation and sound reduction

Firstly, the noise mechanisms are explained and advice given on the determination or use of sound Parameters; the following, for example, may be important:

- the sound power produced by the flow in the pipe;

- the sound power introduced into the fluid and the pipe wall by external sound sources;

- the sound velocities in the fluid and the pipe wall;

- attenuation of the sound transmission in the fluid and in the pipe wall;

- attenuation of the sound transmission in the fluid by deflectors, branches, sudden changes in cross-section and fittings;

- the diminishing sound power in the pipe with increasing pipe length;

- the natural, limit, circumferential expansion and pass frequencies of the pipe;

- the radiation efficiency (or logarithmic radiation efficiency) of the pipe;

- the sound reduction index of the pipe wall.