SDR (or standard dimension ratio) is a method of rating a pipe’s durability against pressure by describing the correlation between the pipe dimension and the thickness of the pipe wall. The lower the SDR the more pressure it can withstand.

 

SDR for BS EN 1401

The British standard BS EN 1401 specify the requirement for pipes in the field of non-pressure underground drainage and sewerage, both outside the building structure and those buried in ground within the building structure. The following table illustrates the relationship between the pipe design and pressure rating for BS EN 1401.

 

SDR for DIN 19534

The following table illustrates the dimensional specifications in compliance with DIN 19534 standard.