This part of EN 10246 specifies the requirements for automatic full peripheral ultrasonic shear wave (including phased array technique) and Lamb wave testing of seamless and welded steel tubes, with the exception of submerged arc-weld (SAW) tubes, for the detection of longitudinal imperfections. This European Standard specifies acceptance levels and calibration procedures. This part of EN 10246 is applicable to the inspection of tubes with an outside diameter > 10 mm, and with an outside diameter-to-thickness ratio ³ 5. For tubes with an outside diameter-to-thickness ratio < 5, one of the options specified in Annex B shall be used by agreement between purchaser and manufacturer. The European Standard EN 10246 "Non-destructive testing of steel tubes" comprises the parts shown in Annex A.