NDT Compliance Regimes in United States

Inspection service providers working in United States deal with 6 distinct regimes: SNT-TC-1A, CP-189, ASNT 9712 (formerly ACCP), 10 CFR 50 Appendix B, T9074-AS-GIB-010/271. They are enforced by different bodies and demand different evidence, so a firm holding one is not thereby compliant with another.

The practical problem in United States is not any single regime but the overlap: a firm bidding across sectors can need several at once, each with its own documents, personnel-certification route, audit cycle and renewal date. 5 of these accept employer-based personnel certification, which means a contracted Level III can sign for the firm; the rest require certification through the scheme itself.

Source: Per-regime research files: SNT-TC-1A; CP-189; ASNT 9712 (formerly ACCP); 10 CFR 50 Appendix B

Regimes governing inspection service providers in United States
Regime	Authority	Applies to
SNT-TC-1A	American Society for Nondestructive Testing (ASNT) publishes it. Nobody enforces SNT-TC-1A directly — it becomes binding when a code, customer or regulator invokes it (ASME BPVC Section V and Section VIII, AWS D1.1, the API inspection codes, prime purchase orders). ASNT Certification Services LLC will audit and accredit a firm's programme against it through the Employer-Based Certification (EBC) Accreditation Program.	Any US inspection service provider whose customer, code or purchase order invokes SNT-TC-1A: weld and fabrication.
CP-189	American Society for Nondestructive Testing (ASNT), approved as an American National Standard by ANSI. Enforced by the contract that invokes it — US Navy and defence supply chains, government and utility procurement — and auditable through ASNT's Employer-Based Certification Accreditation Program, which accredits programmes against SNT-TC-1A, CP-189, or both. The dependent credential, ASNT NDT Level III, is issued by ASNT Certification Services LLC.	Inspection service providers on contracts that call for CP-189 rather than SNT-TC-1A: US Navy and other.
ASNT 9712 (formerly ACCP)	ASNT Certification Services LLC, the entity that manages and operates ASNT's certification programmes. The scheme document is ANSI/ASNT CP-9712 (ISO 9712:2021):2023, the ANSI-approved identical adoption of ISO 9712:2021. Accreditation status differs by programme: ASNT's separate ASNT NDT Level III programme is ANAB-accredited to ISO/IEC 17024, while ASNT has stated it is still pursuing ANAB accreditation for the ASNT 9712 programme.	Individual technicians and Level IIIs at US inspection service providers whose clients require third-party, ISO 9712-style.
10 CFR 50 Appendix B	U.S. Nuclear Regulatory Commission	Directly, it binds NRC licensees and applicants.
T9074-AS-GIB-010/271	Naval Sea Systems Command (NAVSEA); enforced in the field by the cognizant Government inspector — the Supervisor of Shipbuilding at a commercial shipyard, the Shipyard Commander at a government yard	Any activity performing NDT under a NAVSEA contract or on Navy ships and systems — government.
ASME Section V	American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Standards Committee, Subcommittee on Nondestructive Examination; enforced in practice by the referencing Code Section, the Authorized Inspector, and the state or provincial boiler and pressure vessel jurisdiction that has adopted the BPVC	Any NDE contractor examining pressure-retaining items built or repaired to an ASME construction code — Section.

Which NDT compliance regimes apply in United States?

SNT-TC-1A, CP-189, ASNT 9712 (formerly ACCP), 10 CFR 50 Appendix B, T9074-AS-GIB-010/271, ASME Section V. Which of them binds a given firm is set by the sector it works in and by the client contract above it, not by geography alone — a firm doing aerospace and pressure-equipment work in the same city answers to two entirely separate regimes.

Does one approval in United States cover the others?

No. Each is issued by its own authority against its own criteria, and they are not interchangeable. Firms bidding across sectors hold several concurrently, which is why the renewal calendar rather than the initial application is where compliance usually slips.

Can an outsourced Level III cover a firm in United States?

For the regimes accepting employer-based certification, yes — the obligation sits on the employer and a contracted Level III can write and sign the written practice, approve procedures and administer examinations. For the centrally-certified schemes the technicians are certified by the scheme, and the consultant's value shifts to procedures, documentation and audit readiness.

Where do firms in United States most often get caught?

On records rather than capability, and on renewal dates. The work is generally being done correctly; the evidence is either not retained or not retrievable during the audit window, and certificates lapse because renewal was diarised from the wrong date.

How should a firm entering United States sequence its approvals?

By what the first contract requires, not by what looks most prestigious. Approvals take months and cost real money, and an approval the firm is not yet bidding against is capital tied up. Map the target contracts, find the regimes those name, and start with the one gating the nearest bid.

Do US approvals transfer to United States?

Within the US, approvals are still per-scheme rather than universal — an ASNT-compliant written practice does not satisfy Nadcap, and Nadcap does not satisfy a class society. Each regime audits against its own criteria.

Regimes in detail

SNT-TC-1A — Any US inspection service provider whose customer, code or purchase order invokes SNT-TC-1A: weld and fabrication NDT under ASME BPVC.
CP-189 — Inspection service providers on contracts that call for CP-189 rather than SNT-TC-1A: US Navy and other defence and government work,.
ASNT 9712 (formerly ACCP) — Individual technicians and Level IIIs at US inspection service providers whose clients require third-party, ISO 9712-style certification rather than an.
10 CFR 50 Appendix B — Directly, it binds NRC licensees and applicants.
T9074-AS-GIB-010/271 — Any activity performing NDT under a NAVSEA contract or on Navy ships and systems — government and commercial shipyards, regional.
ASME Section V — Any NDE contractor examining pressure-retaining items built or repaired to an ASME construction code — Section I power boilers, Section.