This document applies to flat gaskets for use with flanged joints on process vessels according to DIN 28031, DIN 28033 and DIN 28034. Flat gaskets according to this document are generally a component of a flange sealing system on a pressure vessel or apparatus. When used within the scope of the Pressure Equipment Directive (Directive 2014/68/EU), they are to be regarded as a component of the pressure equipment.