This Standard sets out methods and requirements for the manual ultrasonic testing of full or partial penetration fusion welded joints in carbon and low alloy ferritic steels, 6 mm or greater in thickness, using A-scan presentation and employing four sensitivity levels.This Standard does not cover the testing of stainless steel.It does not cover the testing of longitudinal welds when - (a) the radius of curvature of fabrications is less than 125 mm; or(b) for tubular fabrications having an outside diameter exceeding 250 mm, the ratio of thickness to outside diameter exceeds 0.22.NOTE: Advice and recommendations on information to be supplied by the purchaser at the time of enquiry or order are contained in the purchasing guidelines set out in Appendix A.