Final answer:
SNT-TC-1A outlines that a Level III in NDT has the expertise to establish procedures, oversee training, and certify NDT personnel. It is not true that a Level III requires supervision to perform NDT tasks as they are the supervisory level.
Step-by-step explanation:
The SNT-TC-1A is a document that provides guidelines for personnel qualification and certification in nondestructive testing (NDT). According to the SNT-TC-1A, a Level III individual is someone who has sufficient technical knowledge and experience to be responsible for the establishment and review of NDT methods and procedures, the oversight of NDT training, and the certification of Level I and Level II individuals. Level III individuals also have the authority to interpret codes, standards, and specifications, but it is not true that a Level III can perform NDT tasks without supervision, as by definition, a Level III personnel is considered to be the supervisor or the person who provides guidance in the NDT field.
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