EN ISO 5817 : Welding - Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) - Quality levels for imperfections (ISO 5817:2023).

This document defines three quality levels for imperfections (B, C and D) in fusion-welded joints, excluding beam welding, made from steel, nickel, titanium and their alloys with a minimum thickness of 0.5 mm. It covers full-penetration butt welds and fillet welds, and may also be applied to partial-penetration welds. Level B sets the most stringent requirements. The classification is intended to tailor manufacturing and workmanship quality criteria to the anticipated service conditions: static loads, thermal loads, corrosion and pressure. Annex B provides additional recommendations for fatigue loading.