The manufacturer must have well-maintained welding equipment and experienced welding supervisors. No production welding should be carried out until the welding procedures have been approved and the welding operators qualified. The standards generally used for weld procedure and welder qualification in various countries are summarized in the Guides to National Practice in Section 4.3. The manufacturer is responsible for the documentation and records of weld procedures and welder approvals, which must be available to the inspection authorities. Weld certificates accepted by a recognized inspection authority should be accepted by other inspecting authorities subject to the certificates being current, correct, and suitable for the welding under consideration. This "acceptance" should also be applicable to ultrasonic testing procedures and ultrasonic operators' certificates.