What NDT Certification Actually Requires — Hours, Experience and Examinations
NDT certification in Texas City is employer-based under ASNT SNT-TC-1A: your employer certifies you against its own written practice, which sets training hours, experience months and examination pass marks. ISO 9712 differs — an independent certification body examines and certifies, and the certificate follows you between employers. CP-189 is a standard, and is more prescriptive than SNT-TC-1A.
Texas City sits on a concentrated stretch of Gulf Coast refining and petrochemical capacity, so the certification question here is rarely academic. Contractors bidding turnaround scopes are asked for personnel records before they are asked for rates, and the record that fails an audit is almost never the certificate itself — it is the missing written practice clause, the unsigned Level III examination approval, or an experience log that cannot show method-specific hours. SNT-TC-1A gives recommended minimums; your written practice may exceed them but must not silently fall below them without documented justification. A candidate typically needs classroom training hours by method and level, documented on-the-job experience in that method, and three examinations — general, specific and practical — plus a current near-vision and colour-contrast test. Level III adds a basic examination and method examinations. What follows sets out each element, what auditors actually check, and how a lapsed certification is recovered.
Source: ASNT SNT-TC-1A, Personnel Qualification and Certification in Nondestructive Testing (a recommended practice), Section 6 and Tables 6.3.1A and 6.3.2; ANSI/ASNT CP-189; ISO 9712:2021; ASME BPVC Section V, Article 1, T-120; ASME BPVC Section VIII Division 1; ASME Section IX; AWS D1.1 Clause 8; NAS 410 and EN 4179; OSHA 29 CFR 1910.119(j) mechanical integrity.
| Document | What it is | Who certifies the individual | Does it move with the technician? |
|---|---|---|---|
| ASNT SNT-TC-1A | A recommended practice — guidance an employer adopts and adapts | The employer, against its own written practice | No. It is specific to the employer that issued it |
| ANSI/ASNT CP-189 | A standard, more prescriptive than SNT-TC-1A, with fewer discretionary clauses | The employer, but against fixed requirements it cannot dilute | No, though the fixed baseline makes transfer easier to defend |
| ISO 9712 | A standard for central, third-party certification | An accredited certification body, independent of the employer | Yes. The certificate belongs to the individual |
| NAS 410 / EN 4179 | Aerospace personnel qualification standards | The employer, through an approved and externally checked NDT Level 3 | No, but the Level 3 approval route is externally audited |
| ASNT NDT Level III certificate | A central examination programme run by ASNT | ASNT, by examination | Yes, as portable evidence of Level III knowledge |
Certification Is Something Your Employer Does
Start with the sentence that resolves most of the confusion. ASNT SNT-TC-1A is a recommended practice, not a standard, and ASNT does not certify Level I and Level II technicians. It recommends what an employer's qualification programme should contain. The employer then writes a written practice, and that document — not SNT-TC-1A itself — is what a technician is certified against and what a client auditor asks to see first. The certificate is issued by the employer, over the signature of a responsible Level III.
The consequence is practical and it costs money. Certification does not travel. When a UT Level II leaves one Texas City contractor for another, the new employer does not inherit the old certificate. It may accept the training records and documented experience as evidence and then re-examine, or its written practice may demand a full re-qualification cycle. Written practices differ sharply on this point, and the difference decides whether a new hire is billable in three days or three weeks.
ISO 9712 is built the other way round. An accredited certification body, independent of the employer, examines the candidate and issues the certificate, and that certificate belongs to the individual. It moves between employers and across borders. On the Gulf Coast you meet it mostly on projects with European, Middle Eastern or Asian owners, on equipment fabricated overseas, and in the records of technicians who trained outside North America. Neither scheme is superior. They answer different questions about who is vouching for competence.
What the Written Practice Must Actually State
A written practice that will survive a client audit states, at minimum: the methods and levels the employer certifies; the education, training and experience required for each level in each method; how examinations are prepared, administered and graded, and the pass marks; who the responsible Level III is and how that person is qualified; vision requirements and their frequency; the recertification interval and the basis for recertification; how interrupted service is handled; and how long records are retained. Anything left implicit will be found.
The most common documentary failure is not a missing clause but a version mismatch. An auditor asks for the revision of the written practice that was current on the date the technician was certified. Handing over the 2025 revision to justify a 2021 certification is a finding, because the requirements may have changed in between. Keep superseded revisions, dated, and keep them retrievable. The same applies to the examination question banks, which must be controlled and access-restricted.
The written practice must also state where SNT-TC-1A has been adapted and why. This is legitimate — the recommended practice expects it — but silent departures are not. If your practice reduces UT Level II experience below the tabulated figure because your work is confined to a single narrow application, say so in the document and record the technical justification and the Level III's approval. An undocumented reduction reads to an auditor as an oversight rather than a decision.
Training Hours and Experience by Level and Method
SNT-TC-1A tabulates recommended minimum organised training hours and minimum experience hours for each method and level, keyed to the candidate's education. For the volumetric methods — ultrasonic, radiographic and eddy current — the training figure is around 40 hours at Level I with a similar block again at Level II, and the experience figure runs into the hundreds of hours in that method. The surface methods are far lighter: penetrant and magnetic particle training is measured in single-figure to low double-figure hours.
The number that gets misread is experience. It is hours in the method, not calendar time on a payroll, and it is not interchangeable between methods. A technician with two years on a thickness crew has ultrasonic experience and effectively no radiographic experience, whatever the total service length says. Logs should record method, dates, hours and the type of work performed, and should be signed by a supervisor. Calendar-only logs are the single easiest finding for an auditor to write.
There is also a total-NDT-experience figure alongside the method figure, and a direct-to-Level-II route for candidates who never held Level I. Employers using the direct route must apply the combined requirement rather than the Level II increment alone. ISO 9712 expresses the same idea differently, in months of full-time industrial experience by method and level rather than hours, with part-time experience prorated. Mixing the two accounting systems in one file is a reliable way to fail an audit.
The Three Examinations and the Grading Rule
Certification at Level I and Level II rests on three examinations. The general examination covers the principles of the method and is deliberately employer-neutral. The specific examination covers the equipment, procedures, techniques and codes the employer actually uses, and the acceptance criteria applied to its products. The practical examination is hands-on: the candidate operates the equipment and performs the examination on specimens, graded against a minimum of ten checkpoints.
SNT-TC-1A recommends a composite grade of at least 80 percent with no individual examination below 70 percent. Employers frequently transcribe that rule incorrectly, recording only a composite figure and losing the per-examination floor. If a candidate scored 95 on the general, 92 on the practical and 62 on the specific, the composite passes and the certification does not. Grade sheets should show all three scores, the composite, and the signature of the person who graded them.
The specific examination is where corners get cut. A purchased, off-the-shelf question set that never names your procedures, your instruments or the code your client works to is not, by definition, a specific examination. It should reference the actual written procedures by number. On the Gulf Coast this matters commercially as well as technically: when a refinery owner audits a contractor's personnel files, a generic specific examination signals that the qualification programme is administrative rather than real.
Vision, Recertification and Interrupted Service
Vision is the requirement most often out of date in an otherwise clean file. Near-vision acuity must be demonstrated in at least one eye, corrected or uncorrected, sufficient to read a Jaeger Number 1 or equivalent type at not less than about 30 centimetres, and colour or grey-scale contrast differentiation must be demonstrated where the method depends on it. The test is expected annually. A certificate valid on paper alongside a vision test from three years ago is a finding, and in some client contracts it invalidates the reports produced since.
Recertification is set by the written practice within the recommended ceiling — SNT-TC-1A points to intervals not exceeding five years, and many refining and petrochemical written practices tighten that to three. Recertification may rest on evidence of continuing satisfactory technical performance, on re-examination, or on a combination. Whichever route the written practice chooses, it must choose one explicitly; a practice that merely says technicians are recertified periodically has not stated a requirement.
Interrupted service is the clause everyone forgets until they need it. If a technician is away from a method for an extended period, the written practice should state the threshold that triggers re-examination and what form that takes. Recovery of a lapsed certification is normally a practical examination plus a specific examination, not a full retraining cycle, provided the original training and experience records still exist. Which is the real argument for keeping those records long after the certificate expires.
Level III: Employer Level III Versus ASNT Level III
A Level III establishes the techniques, approves procedures, and administers, grades and signs off the qualification of Level I and Level II personnel. Under SNT-TC-1A the employer may certify its own Level III, using the ASNT Level III examination route as evidence or by employer examination. The ASNT NDT Level III programme itself involves a basic examination covering SNT-TC-1A, materials and processes, and the fundamentals of other methods, plus a method examination for each method held.
Smaller Texas City contractors commonly retain an outside Level III under contract rather than employing one. This is entirely acceptable and widespread, but the arrangement must be visible in the written practice: the Level III must be named, their responsibilities defined, and the extent of their authority to sign examinations and approve procedures set out. An outside Level III whose only trace in the system is a signature on a certificate does not satisfy an audit that asks who exercises technical control.
Holding an ASNT NDT Level III certificate does not automatically make someone the responsible Level III for an employer. The certificate is portable evidence of knowledge; the authority is granted by the employer's written practice. The distinction matters when a client asks who approved a procedure and the answer turns out to be a consultant who has never been formally designated in the document.
Where the Requirement Comes From in Texas City
Texas City's inspection demand is generated by a dense concentration of refining, petrochemical and terminal operations on Galveston Bay, with deepwater marine loading, extensive tank farms, and units running crude, cracking, reforming and olefins chemistry. That base pulls in fabrication shops, scaffold and insulation contractors, and inspection houses that live on the turnaround calendar. Every one of them is asked for personnel qualification records by the owner before a scope is released.
The requirement itself is imposed in layers. ASME Section V, Article 1, T-120 sends personnel qualification back to SNT-TC-1A or CP-189, with the referencing code section deciding which. ASME Section VIII Division 1 and ASME B31.3 then set what must be examined and to what acceptance criteria. AWS D1.1 governs structural steel and adds its own requirements on top of the employer's written practice for UT technicians. In-service, the API inspection codes require examinations to be performed by qualified NDT personnel.
Above all of that sits OSHA's process safety management rule, whose mechanical integrity provisions require inspections and tests on covered process equipment to be performed by trained and qualified personnel, with records kept. Texas City's history — including the 2005 refinery explosion and the Chemical Safety Board investigation that followed — is why owners in this complex treat contractor competency documentation as a live compliance question rather than a procurement formality.
The Audit Findings That Recur
Five findings account for most of what we see in Gulf Coast personnel audits. First, the written practice is signed by a Level III who does not hold certification in the method being certified — a Level III in UT signing MT certifications, with no MT-qualified Level III anywhere in the chain. Second, experience logged in months rather than method hours, so the file cannot demonstrate the tabulated requirement was met at all.
Third, vision tests lapsed or missing for part of the certification period, discovered only when a client traces a specific report back to the technician who signed it. Fourth, the specific examination is generic and references no employer procedure, which tells an auditor the programme was assembled to satisfy a checklist. Fifth, no controlled record of which revision of the written practice was current at each certification date.
None of these is expensive to fix in advance and all of them are expensive to fix during a bid evaluation or a client audit. The pattern is consistent: the technical competence of the technicians is rarely the problem. The documentation that proves it is. Building the written practice, the examination bank and the records system so that they answer an auditor's questions in the order the auditor asks them is a separate skill from performing the examinations, and it is the one most contractors under-invest in.
Does ASNT certify NDT Level I and Level II technicians?
No. For Level I and Level II under SNT-TC-1A, the employer certifies. ASNT publishes the recommended practice and runs central examination programmes at Level III, but the Level II certificate in a Texas City contractor's personnel file is issued by that contractor, against that contractor's written practice, over the signature of its responsible Level III. Confusing the two is the most frequent error technicians make when explaining their credentials to a client.
Is API 510, 570 or 653 inspector training part of this offer?
No. Atlantis NDT does not deliver API 510 pressure vessel inspector, API 570 piping inspector or API 653 tank inspector certification training, and does not act as the API inspector of record or as a PSM auditor. What we deliver is NDT method training and certification preparation to SNT-TC-1A and ISO 9712 at Levels I, II and III, plus ASNT Level III consulting. Those are different credentials serving different roles.
How many training hours does SNT-TC-1A recommend for ultrasonic testing?
Under SNT-TC-1A's recommended minimums for a high school graduate, ultrasonic testing calls for about 40 hours of organised classroom training at Level I and a further 40 hours at Level II, with roughly 210 hours of documented ultrasonic experience before Level I examination and around 630 hours accumulated in the method for Level II. Radiography and eddy current sit at similar figures. Surface methods are far lower. Your written practice governs the actual numbers.
Can a degree reduce the required experience?
Yes, within limits. SNT-TC-1A allows reduced experience for candidates who have completed engineering or science study beyond high school, and CP-189 handles the same substitution with tighter wording. What no education route removes is method-specific experience: an engineering degree does not substitute for hours spent actually performing ultrasonic examinations. Auditors read the substitution clause in your written practice and then check that the reduced hours were still logged by method.
What happens to certification when a technician changes employers in Texas City?
It does not transfer. The new employer must certify the technician under its own written practice. In practice most Gulf Coast contractors accept documented training and prior experience as evidence, then administer their own specific and practical examinations — the specific examination especially, because it must cover that employer's procedures, equipment and codes. Some written practices require a full re-examination cycle. That single clause decides whether a new hire bills within days or weeks.
What does a practical examination actually involve?
The candidate sets up and operates the equipment and performs the examination on one or more specimens, and is graded against a minimum of ten checkpoints covering equipment operation, technique, detection and recording. It is not a paper exercise. In UT that means calibrating on a block, demonstrating repeatability, and recording indications the examiner has already characterised. In MT it means demonstrating field adequacy and correct sequencing rather than simply finding the flaw.