This document specifies requirements for qualification of welding operators and weld setters for mechanized and automatic welding of metallic materials. This document does not apply to personnel who: do not control or adjust welding parameters; or are not involved in the setup of welding equipment. Annex A specifies requirements for the functional knowledge of the welding unit. Annex B gives guidance on necessary knowledge of welding technology. Qualification of welding operators and weld setters for friction stir welding and friction stir spot welding are not covered by this document, see ISO 25239-3 and ISO 18785-3 respectively. The principles of this document may be applied to other processes not covered by this document.