ASNT

8. Evaluation is performed according to acceptance criteria to identify items suitable for service. 9. Reports (records) provide the means to document specific test methods, equipment used, personnel performing activity, date performed, and test results. 10. Attachments may include (if required) items such as report forms, instrument calibration forms, a qualified equipment matrix, and schedules. Once the procedure is completed, typically an expert in the subject matter performs a technical evaluation. If the procedure is deemed adequate (meeting identified requirements), the expert will approve it for use. Some codes and standards also require the procedure to be qualified — that is, demonstrated to the satisfaction of a representative of a regulatory body or jurisdictional authority. TEST SPECIFICATIONS FOR NONDESTRUCTIVE TESTING Nondestructive testing specifications must anticipate a number of issues that arise during testing. Test Condition Requirements 1. What and where are the items to be inspected? 2. What are the target discontinuities and where are they in the item (surface, internal, or both)? 3. Are there any environmental and safety considerations (such as temperature, ventila- tion, confined space and/or radiation) that must be addressed? If applicable, do any of the environmental conditions prevent personnel access and/or impact performance of NDT methods/techniques to be used? Technique Selection 1. Does a code or standard dictate a specific test technique? 2. Nondestructive test methods must be selected to detect the target discontinuities. The approaches may be established by applicable codes and standards. If not, they must be determined by a subject matter expert. Subject matter experts document their expertise through established certification programs.

3. What type of documentation is required? In most of its literature in the 21st century, ASNT distinguishes between methods and techniques. Broadly, a method is a category of testing techniques that have the same interrogat- ing energy — for example, radiographic testing or ultrasonic testing. A technique is a category within a method and is defined by a particular means — for example pulse echo ultrasonic testing or through-transmission ultrasonic testing. Interpretation Interpretation may be complex because of the technique selected and the component configura- tion or presence of unknown materials, such as inserts and repairs. Discontinuities may be detected primarily through pattern recognition or image interpretation by an experienced inspector. Beware of false calls or missed discontinuities caused by component design, material type, inspection technique, or personnel. STANDARDS AND SPECIFICATIONS FOR NONDESTRUCTIVE TESTING Standards have undergone peer review in industry and can be invoked with the force of law by contract or by government regulation. In contrast, a specification represents an employer’s instruc- tions to employees and is specific to a contract or work place. Specifications may form the basis of standards through a review process. Standards and specifications exist in three basic areas: equipment, processes, and personnel. 1. Standards for equipment and materials include electronic and optical equipment. Standardized reference objects such as calibrated radiation detectors would also fit in this category. 2. ASTM International (formerly the American Society for Testing and Materials) and other organizations publish standards for test techniques (Annual Book of ASTM Standards). Standards for quality assurance are not specific to a test technique or even to inspection in general.

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Part 3