This document specifies how a preliminary welding procedure specification is qualified based on preproduction welding tests. This document is applicable to arc welding, gas welding, beam welding, resistance welding, stud welding and friction welding of metallic materials. The principles of this document may be applied to other welding processes. This document is a part of a series of standards dealing with specification and qualification of welding procedures. Details are given in ISO 15607. The use of this document can be restricted by an application standard or specification.