Codes, regulatory requirements, standards, specifications, and recommended practices are used in all aspects of construction, fabrication, manufacturing and inspection. The following is a brief description of each of these categories along with examples of how they are used.
Codes:
Codes are generally the top-tier documents, providing a set of rules that specify the minimum acceptable level of safety for manufactured, fabricated or constructed objects. These may incorporate regulatory requirements and will often refer out to standards or specifications for specific details on additional requirements not specified in the Code itself. Examples of some commonly used Codes are the ASME Boiler and Pressure Vessel Code (B&PVC) and the AWS D1.1 Structural Welding Code – Steel. The B&PVC covers pressure-related equipment from refineries and unfired pressure vessels to nuclear power generation, and the AWS D1.1 Code covers welded structures of all types.
Standards
Standards are documents that establish engineering or technical requirements for products, practices, methods, or operations. Of interest to NDT personnel are those standards that provide personnel certification requirements and those that provide requirements for performing NDT tasks.
Examples of certification standards are the ANSI/ASNT CP-189, ASNT Standard for Qualification and Certification of Nondestructive Testing Personnel and the ANSI/ASNT CP-105, ASNT Standard Topical Outlines for Qualification of Nondestructive Testing Personnel. Examples of NDT performance standards are the ASTM Standard E 709, Standard Guide for Magnetic Particle Testing, and ASTM E 1444, Standard Practice for Magnetic Particle Testing.