ISO 9328-5:2011 specifies the requirements for flat products for pressure equipment, made of thermomechanically rolled weldable fine grain steels. The steels are not suitable for hot forming.

Until now, no sufficient data for the standardization of the elevated temperature properties of these steels are available. If their use at such temperatures is intended, the conditions for this are specially agreed upon between the interested parties.

The requirements and definitions of ISO 9328-1:2011 also apply to ISO 9328-5:2011.