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Personnel Qualification and Certification in Nondestructive Testing

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Publications Frequency for SNT-TC-1A

SNT-TC-1A is published every four years, the next release is scheduled in 2020. This will be followed by a scheduled release in 2024 and another in 2028, unless there are extenuating circumstances that warrants a new revision to be published sooner.

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NDT certification programs are divided into two major types:

  1. Employer-based programs
  2. Central certification programs.

SNT-TC-1A is an Employer-based program, where employers develop, administer, and grade their own qualification examinations. In an employer-based system, a person’s certification is terminated when the individual leaves that company.

SNT-TC-1A is not a specification. It is a set of guidelines or recommendations to employers about how to establish and conduct an NDT or predictive maintenance (PdM) personnel qualification and certification program.

SNT-TC-1A has three requirements that must be met.

  1. The employer shall prepare a written practice or procedure for qualifying and certifying company NDT personnel and shall be responsible for personnel certifications. This document shall be on file and approved by the employer’s Level III.
  2. The employer shall modify SNT-TC-1A as necessary, to ensure the qualification and certification requirements are satisfactory for the NDT work that the company’s employees will perform. Note: Modifications may alter but shall not eliminate basic provisions of the program such as training, experience, testing, and recertification. Supporting technical rationale for modification of detailed recommendations should be provided in an Annex to the written practice.
  3. Personnel certification shall be recertified per the conditions in SNT-TC-1A and is revoked when employment is terminated.

Once the employer has an approved written practice it is now a procedural requirement and shall be fully complied with. Depending on who the employer’s customer are, may require the written practice to be approved by the customer.

SNT-TC-1A Committee

The SNT-TC-1A committee is responsible for maintaining SNT-TC-1A under the direction and guidance of the Standards Council. The committee responsibilities include:

  1. Working with the ASNT Technical and Education (T&E) Council method committees to incorporate any changes.
  2. Reviewing inquiries related to SNT-TC-1A to determine if action is required for the next revision.
  3. Maintaining a working group (panel) that addresses requests for interpretation of SNT-TC-1A. 

Meeting Notice

The next meeting will be an in-person and virtual on Monday, October 31, 2022 from 8:00 a.m. to 12:00 p.m. CT. All directly and materially affected persons are welcome to attend and should e-mail for additional information.

Download the meeting agenda

SNT-TC-1A – Interpretations

Having trouble understanding what the expectation is or need to confirm your interpretation is correct? Submit an interpretation request. (Request Form in PDF or Word formats.)

Within the SNT-TC-1A committee, there is a dedicated group of volunteers that addresses interpretations. Whenever the ISC receives an interpretation request for SNT-TC-1A, ISC staff will review to determine if an interpretation has been previously submitted. If not, the information is logged and forwarded to the interpretation panel to review and recommend a course of action. That recommendation is then sent out to the SNT-TC-1A committee for vote and then the ISC will communicate the response to the originator of the interpretation. Depending on the outcome of the interpretation, it may be considered necessary to propose a change to SNT-TC-1A as a result of the interpretation. Below shows the flow chart of the SNT-TC-1A Interpretation Process.

SNT-TC-1A Inquiry Process R1

SNT-TC-1A – Proposing Changes

SNT-TC-1A is revised and republished every four years. In between publishing cycles, ISC receives questions, comments, and proposed changes from the public. If you have any proposed changes, send those to the ISC for review by the committee ( All the committee asks is the proposer includes rationale for making any proposed changes to the document. This will assist in expediting the proposal.