Interpreting SNT-TC-1A
This month’s Q&A features the responses from the SNT-TC-1A Interpretation Panel to inquiries submitted in 2025 about Recommended Practice No. SNT-TC-1A: Personnel Qualification and Certification in Nondestructive Testing. The responses clarify the intent of ASNT’s councils and the recommendations of SNT-TC-1A.
Inquiry 25-01
2020 Edition
Paragraph 8.7
INQUIRY
As an ISO 9712 Level III, what must I do to satisfy the Level III requirements of SNT-TC-1A?
RESPONSE
The 2020 Edition of SNT-TC-1A requires the candidate to successfully complete the Basic, Method, and Specific examinations. While it is possible to use an ISO 9712 Level III certification to meet some or all of the SNT-TC-1A requirements, there are specific provisions that must first be met. See SNT-TC-1A Inquiry 24-43. ASNT cannot speculate on what satisfies ASME requirements.
Inquiry 25-02
2020 Edition
Paragraphs 8.5.4 and 8.5.5
INQUIRY
Can the maximum allowance number of false calls be specified as a maximum percentage instead of an absolute number in the written practice?
RESPONSE
Yes. Paragraph 2.1.7, Detection Rate, permits the use of either a percentage or a number.
Inquiry 25-03
2020 Edition
Paragraphs 8.1 and 4.3.3
INQUIRY
If I have only one Level III, and they are the person with whom I have assigned responsibility for the testing methods for which they are qualified, who is supposed to approve their certification exams if Paragraph 8.1 requires the responsible Level III to approve the exams?
Do I need to hire another Level III and assign them responsibility for the methods for which they are qualified in order to approve the Level III exams?
RESPONSE
Yes; yes. See Inquiry 24-38. Note: Those Level III examinations are also required to be administered under the auspices of a Level III.
Inquiry 25-04
2020 Edition
Paragraph 12.2
INQUIRY
Based on the wording from Paragraph 12.2 that the certification is effective for a maximum interval of 5 years after the Certifying Authority signs the certification certificate, if the certification certificate has to be re-signed by the Certifying Authority after two (2) years due to an error in the initial certificate, does the certification now extend five (5) years from the new signature date?
RESPONSE
No. Certification is a written testimony of qualification and requires recertification at intervals not to exceed five (5) years. Correcting errors on a certificate of certification does not constitute recertification as discussed in Paragraph 12.1.
Inquiry 25-05
2024 Edition
Paragraph 8.1
INQUIRY
Can a QA manager who is a qualified representative but not qualified as a Level III create and sign off on Level III examinations?
If the answer to 1 is no, are they required to seek an outside Level III for approval?
RESPONSE
No.
Yes, if there is no in-house Level III to write and approve the qualification examinations.
Inquiry 25-06
2024 Edition
Paragraphs 8.1.7 and 8.1.8
INQUIRY
Regarding the change to Paragraph 8.1.7, can our company-delegated NDT Level III still administer the examination and recertification of our NDT Level II personnel?
Is it necessary to use a third party for recertification?
RESPONSE
Yes. Paragraph 8.1.7 applies IF the employer is contracting outside services.
No.
Inquiry 25-07
2024 Edition
Paragraph 6.3.2
INQUIRY
Does the last sentence of Paragraph 6.3.2.3 mean, for example, that you could meet the Level III experience requirements with one (1) year of completed engineering or science study and three (3) years of Level II equivalent work experience?
RESPONSE
Yes, provided those alternatives to the SNT-TC-1A recommendations are addressed in the employer’s written practice. Keep in mind that when alternatives to SNT-TC-1A recommendations are used, they could be challenged by a customer, so solid justification should be considered prior to making changes to the recommendations of SNT-TC-1A.
Inquiry 25-08
2024 Edition
Paragraph 8.2.1
INQUIRY
Is it the intent of Paragraph 8.2.1 to perform the visual acuity examination with either one eye or both eyes simultaneously?
RESPONSE
Yes.
Inquiry 25-09
2020 Edition
Paragraph 8.1.2
INQUIRY
If a Level III is designated as a qualified representative by a Level III who is certified in a method, can a Practical examination in that method be administered by that designated Level III who is not certified in the method?
RESPONSE
No.
Inquiry 25-10
2024 Edition
Paragraph 8.2.2
INQUIRY
May a candidate who fails the Ishihara color test charts still be eligible for certification under SNT-TC-1A?
Are there alternative recommended methods for testing color-contrast differentiation in cases of partial color vision deficiency?
RESPONSE
Yes, Paragraph 8.2.2 requires a candidate to distinguish and differentiate contrast among the colors or shades of gray used in the test methods they will be employing, as determined by the employer.
Inquiry 25-11
2024 Edition
Paragraph 7.1
INQUIRY
Could you clarify what is meant by “track hours” as stated in Paragraph 7.1?
RESPONSE
“Track hours” means to accurately document the individual’s course of progress in time (hours), as they complete each portion of the training course.
Inquiry 25-12
2024 Edition
Paragraph 8.2.1
INQUIRY
Must a person whose visual acuity requires them to wear corrective lenses wear them for the entire examination process?
RESPONSE
Yes.
Inquiry 25-13
2024 Edition
Paragraphs 8.5.3, 8.5.4, and 8.5.5
INQUIRY
Is it the intention that the samples for the practical or technical performance evaluation have flaw dimensions comparable to the acceptance criteria of the NDT procedure used for evaluation?
If the answer to the above question is yes, is it the intention that a sample be chosen for each of the various acceptance criteria that an employer may work with?
Is it acceptable for the Level III to determine what samples are to be used per Paragraphs 8.5.4 and 8.5.5, regardless of the acceptance criteria used?
Is it the intent to restrict an employer to a specific-sized flaw or “difficulty level” when selecting a flawed specimen to challenge an individual during the evaluation?
RESPONSE
No.
N/A.
Yes.
No.
Inquiry 25-14
2024 Edition
Paragraph 2.1.4
INQUIRY
Is it required that the designation of the Certifying Authority be within the written practice?
Is it acceptable to have the Certifying Authority be designated in an addendum to the written practice?
Can an alternate method, such as a designation letter, be used for designating the Certifying Authority?
If yes to number 3 above, does the process need to be outlined in the written practice for how the designation of the Certifying Authority shall be performed?
If the designation of the Certifying Authority can be in an addendum to the written practice or a separate document, must the addendum or separate document be signed by the Level III?
Who is responsible for designating the Certifying Authority?
RESPONSE
The position of the Certifying Authority needs to be addressed in the written practice, not the person who is the Certifying Authority.
See response 1.
A letter that designates the person who is the Certifying Authority should be issued.
See response 1.
See response 1.
A senior responsible person of the employer.
Inquiry 25-15
2024 (addendum) Edition
Paragraphs 8.1.3 and 8.1.3.1
INQUIRY
Is it the intent of ASNT that the Level II General or Specific examination be multiple choice and contain no true-or-false, yes-or-no, or fill-in-the-blank type questions, and be modeled after the ASNT Questions & Answers books?
Is it the intent of ASNT that the Level III General or Specific examination be multiple choice and contain no true-or-false, yes-or-no, or fill-in-the-blank type questions?
Are these types of questions valid, provided that the individual who approved them is a Level III in the method?
RESPONSE
No, while SNT-TC-1A does not prohibit these types of questions, the intent is illustrated in Paragraph 8.1.3.
No, while SNT-TC-1A does not prohibit these types of questions, the intent is illustrated in Paragraph 8.1.3.
Yes.
Inquiry 25-16
2024 (addendum) Edition
Paragraphs 8.1.3 and 8.1.3.1
INQUIRY
If a question is taken verbatim from ASNT study materials, but the answer choices are completely different, is this still considered verbatim?
If a question is reworded, is it still considered verbatim? For example, question 36 of the liquid penetrant Q&A Book Level I reads: “Which of the following are commonly accepted methods for applying penetrant?” If reworded to “All of the methods below are considered acceptable in applying penetrants except for which of the following?” (with all of the answers reworded as well), would this be considered verbatim?
What is ASNT’s definition of verbatim?
RESPONSE
See Interpretations 24-29 and 24-32. Note: The intent of administering a written examination is to test the candidate’s knowledge and understanding of a particular NDT method, not the ability of a candidate to memorize published training and example questions.
Inquiry 25-17
2024 Edition
Paragraph 6.0
INQUIRY
Inquiry 22-06 states that an employer may accept a signed affidavit as an alternative to possessing documented evidence of training, provided that there is a process outlined in the employer’s written practice, supported by previous certification documentation, and approved by the Level III. Does this also apply to other types of documentation, such as experience records, educational background documentation, etc.?
RESPONSE
Yes.
Inquiry 25-18
2020 Edition
Table 6.3.1A, Note 11
INQUIRY
Is Note 11 of Table 6.3.1A speaking only about the three UT techniques—FMC, TOFD, and PAUT—or is this to be interpreted as applying to all automated and semiautomated systems for different methods?
RESPONSE
While Note 11 of Table 6.3.1A specifically addresses those three UT techniques, the written practice should reflect the education, training, experience, and examination requirements for each method and technique used by the employer.
Inquiry 25-19
2024 Edition
Sections 5 and 6 – NDT Level III Responsibilities and Written Practice Requirements
INQUIRY
We are seeking confirmation on whether an NDT Level III is required to approve procedures, or whether an employer may instead designate a P.E., degreed engineer, and/or Level II personnel to perform these functions if documented in the written practice.
RESPONSE
This is currently outside the scope of SNT-TC-1A.
Inquiry 25-20
2011 Edition
Paragraph N/A
INQUIRY
Must training be conducted by a Level III or may it be delegated to someone else?
RESPONSE
Training may be conducted by an individual appointed and documented by an NDT Level III; however, all training programs should be approved by the NDT Level III responsible for the applicable method.
Inquiry 25-21
2020 Edition
Table 6.3.1A
INQUIRY
Are the recommended minimum training hours listed in Table 6.3.1A based upon a high school diploma or GED?
RESPONSE
The training hours listed in Table 6.3.1A are the minimum hours required regardless of education level.
Inquiry 25-22
2024 Edition
Paragraphs 2.1.9 and 2.1.23
INQUIRY
Please clarify the mandatory certification steps for supplemental NDT personnel sourced from a third-party agency that does not certify those individuals.
RESPONSE
Certification is the responsibility of the employer in accordance with the employer’s written practice. If a third party provides personnel who hold no certifications, those individuals must meet the requirements of the written practice to which they are being certified. The Level III responsible for implementing the written practice is responsible for verifying that personnel being certified meet the education, training, experience, and examination requirements stated in the written practice.
Inquiry: 25-23
2024 Edition
Paragraphs 2.1.9 and 2.1.23
INQUIRY
If an independent contractor develops a written practice and then contracts an outside Level III service to administer the required certification examinations to him, and then attests that all of the education, training, experience, and examination requirements have been met in accordance with the written practice, may that independent contractor then sign the certification record as the Certifying Authority?
RESPONSE
Yes, provided the position of Certifying Authority is described in the written practice and how the outside Level III services are used.
Inquiry: 25-24
2020 Edition
Paragraphs 2.1.10 and 9.4.3
INQUIRY
What type of documentation is acceptable for proof of experience for NDT personnel?
RESPONSE
Various forms of documentation supporting proof of experience may be used, provided that the documentation supports the NDT method experience required and is found to be acceptable to the Level III.
Inquiry: 25-25
2020 Edition
Paragraph N/A
INQUIRY
May certification examination questions be developed by using excerpts from study guides?
RESPONSE
The intent of administering a written examination is to test the candidate’s knowledge and understanding of a particular NDT method, not the ability of a candidate to memorize published training and example questions. This inquiry would meet the intent of question development for written examinations.
Inquiry 25-26
2020 Edition
Paragraph N/A
INQUIRY
If a Level III is being contracted to a company as a Level III outside agency, what certification requirements must that individual meet?
RESPONSE
This is a contractual issue, but in general, the Level III must meet the requirements determined by the company contracting the outside service as meeting the minimum requirements of their NDT program and written practice.
