ASNT
ASNT SNT-TC-1A
Personnel Qualification and Certification in Nondestructive Testing
A recommended practice rather than a certification scheme, and the distinction is the point. It tells an employer what their own written practice must cover - training hours, experience, examinations and recertification for Levels I, II and III - and the employer then certifies their own people against it. So an SNT-TC-1A Level II is certified by a company, not by a body, and the first thing to audit is the written practice itself.
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