The ASNT Certification Services LLC NDT Level III program provides third-party certification for nondestructive testing (NDT) personnel whose specific jobs require knowledge of the technical principles underlying the nondestructive tests they perform, witness, monitor, or evaluate. The program provides a system for ASNT NDT Level III certification in NDT in accordance with Recommended Practice No. SNT-TC-1A.

Certification under this program results in the issuance of an ASNT Certification Services LLC certificate and wallet card attesting to the fact that the certificate holder has met the published guidelines for the Basic and Method examinations as detailed in Recommended Practice No. SNT-TC-1A.

The ASNT NDT Level III program is the core certification program for ASNT Certification Services LLC. Inaugurated in early 1977, ASNT NDT Level III certificates are recognized worldwide.