CWI vs ASNT Level 2 — Welding Inspector or NDT Technician?
AWS Certified Welding Inspector (CWI) per QC1 certifies welding inspection knowledge for AWS code work. ASNT NDT Level II per SNT-TC-1A or CP-189 certifies a specific NDE method (UT, RT, MT, PT, VT, ET) for general industrial inspection. Many welds need both.
One-Sentence Decision Rule
If your work is welding-specific inspection — visual acceptance to AWS D1.1, D1.5, D1.6, B31.1 or similar — you need a CWI. If your work is general NDT (forgings, castings, aerospace components, pressure-vessel volumetric inspection), you need an ASNT Level II in the relevant method (UT, RT, MT, PT, VT, ET). Most weld-inspection roles end up needing both, in different combinations, because the codes recognize different certifications for different tasks.
What Each Certifies
| Attribute | AWS CWI (per QC1) | ASNT NDT Level II (per SNT-TC-1A or CP-189) |
|---|---|---|
| Issuing body | American Welding Society (AWS) | American Society for Nondestructive Testing (ASNT) or employer (under SNT-TC-1A) |
| Scope | Welding inspection: visual acceptance, code interpretation, documentation | One specific NDE method (UT, RT, MT, PT, VT, ET, AET, etc.) — not weld-specific |
| Governing standard | AWS QC1 — Standard for AWS Certification of Welding Inspectors | ASNT SNT-TC-1A (Recommended Practice, employer-administered) or ANSI/ASNT CP-189 (national standard, centralized exam) |
| Number of certifications needed | One CWI covers all welding codes the inspector applies | One certification per NDE method — UT Level II is separate from MT Level II is separate from RT Level II |
| Cert validity | 3 years; 9-year recertification cycle | Typically 5 years per ASNT employer practice (varies by employer/method) |
| Recognized by AWS D1.1? | Yes — one of five paths in Clause 8.1.4.2 | Yes — for NDT (Clause 8.14.6) and as an alternate visual path (Clause 8.1.4.2(4)) |
| Recognized by ASME BPVC? | Sometimes (for visual); ASME prefers ASNT for NDE methods | Yes — ASME BPVC Section V references SNT-TC-1A and CP-189 |
CWI Exam Structure (per AWS QC1)
The AWS CWI examination has three parts — all required, each scored independently with a 72% passing mark per QC1 6.2.2:
| Part | Minimum Questions | Passing Mark | Subject |
|---|---|---|---|
| Part A — Fundamentals | 150 | 72% | Welding processes, metallurgy, NDT, math, weld symbols |
| Part B — Practical | 40 | 72% | Hands-on inspection of plastic replicas using a generic specification |
| Part C — Code Book | 46 | 72% | Applied questions on the AWS code chosen by the applicant (D1.1, D1.5, D1.6, B31.1, API 1104, ASME B31.3, etc.) |
Per QC1 6.2.3, an applicant who achieves a 72% overall composite score (simple average of the three parts) but fails one or more individual parts may retake the failed parts. Per QC1 6.2.5, the maximum number of retests in a three-year period from the original test date is three; only one retest is permitted without documented evidence of additional training. A full 3-part reexamination requires 40 hours of further training (QC1 6.2.5.1); a 1-part or 2-part retest requires 16 hours specific to the failed subject (QC1 6.2.5.2).
AWS may also use a split-examination format per QC1 6.2.7: applicants take Part A first, must achieve 72% to qualify, then attempt Parts B and C on the same day. Applicants who score 60% or higher on Parts B and C but below the 72% needed for CWI earn the lower CAWI (Certified Associate Welding Inspector) credential per QC1 6.2.7.2. CAWI certification is valid for up to three years and is not eligible for renewal — it is intended as a stepping stone to CWI per QC1 14 and 15.1.
Senior CWI (SCWI) applicants take a combined Part A and Part B examination of at least 200 questions at the same 72% threshold per QC1 6.1.2, with an experience prerequisite beyond CWI.
ASNT Level 2 Exam Structure
ASNT Level II is method-specific. There is no single "ASNT Level 2" examination — an inspector who needs to perform UT, RT, MT, and PT obtains four separate Level II certifications, each with its own general examination, specific (method) examination, and practical examination. The structure is defined by the certifying program:
SNT-TC-1A (Employer-Administered)
SNT-TC-1A is a Recommended Practice published by ASNT. Under SNT-TC-1A, the employer establishes a Written Practice that defines training-hour minimums, examination content, and qualification levels for each NDE method. The employer (typically through an in-house Level III) administers the General, Specific, and Practical examinations and certifies the inspector. Certification is portable only between employers that recognize the issuing employer's Written Practice — it is not a centrally-validated credential.
ANSI/ASNT CP-189 (National Standard)
CP-189 is an ANSI national standard. Where SNT-TC-1A is a "may use" recommended practice, CP-189 is a "shall use" standard with stricter qualification, examination, and recertification requirements. Some industries (notably aerospace and certain pressure-vessel work) require CP-189-level certification rather than employer-based SNT-TC-1A.
ASNT Central Certification Program (ACCP) and ISO 9712
For inspectors needing third-party (not employer-administered) certification, ASNT offers the ACCP, and equivalent third-party programs include ASNT CP-9712, CAN/CGSB-48.9712, and ISO 9712. AWS D1.1:2025 Clause 8.14.6.3 recognizes all of these as valid for NDT personnel performing inspections under D1.1.
For current method-specific exam content, training-hour minimums, fee structures, and recertification rules, see the ASNT certification programs page — these change between SNT-TC-1A revisions and across ASNT's certification offerings.
Which Standards Recognize Which Cert
D1.1:2025 separates inspector qualification into two categories: visual inspection personnel (Clause 8.1.4) and NDT personnel (Clause 8.14.6). The two categories have different acceptable certification paths.
Visual inspectors per D1.1 Clause 8.1.4.2
Per Clause 8.1.4.2, inspectors responsible for acceptance or rejection on the basis of visual inspection shall be qualified by ONE of the following five paths:
- AWS CWI or SCWI per AWS QC1
- CSA W178.2 Level 2 or Level 3 Welding Inspector
- AWS B5.1 Welding Inspector (WI) or Senior Welding Inspector (SWI)
- NDT Level II VT per SNT-TC-1A or ANSI/ASNT CP-189
- An individual who, by training or experience or both in metals fabrication, inspection, and testing, is competent to perform inspection of the work
So D1.1 explicitly recognizes ASNT NDT Level II VT as a valid alternative to CWI for visual inspection. Path 5 leaves substantial Engineer discretion for non-traditional qualifications.
NDT inspectors per D1.1 Clause 8.14.6
Per Clause 8.14.6.1, personnel performing NDT other than visual testing shall be certified as NDT Level II in the test method and technique, or NDT Level I working under the supervision of a Level II. Per Clause 8.14.6.2, employer-based certification follows either ASNT SNT-TC-1A or ANSI/ASNT CP-189, with Level III personnel certifying Level I and II individuals. Per Clause 8.14.6.3, third-party certification options include ACCP, ASNT CP-9712, CAN/CGSB-48.9712, or ISO 9712.
Importantly, per Clause 8.14.6.5, NDT personnel performing inspections under 8.14.6 are exempted from the AWS QC1 (CWI) requirements. So the UT, RT, MT, or PT inspector on a D1.1 job does not need to be a CWI — the ASNT method certification is sufficient.
“A CWI signs off on the visual inspection package; an ASNT Level II runs the volumetric NDE. On most fabrication jobs you need both people, often the same human holding both certifications.”
Practitioner observation, common practice on AWS D1.1:2025 structural-steel work
Recertification Cycles
Per QC1 10.1, AWS CWI certification is valid for three years from the first day of the month following the date of examination. Renewal requires submission of an approved renewal application before the expiration date (no earlier than 11 months prior), and the inspector must attest per QC1 15.4 to having had no period of continuous work inactivity greater than two years in welding-inspection activities during the previous three years. A 60-day administrative extension is permitted.
Per QC1 15.5, renewals are limited to two consecutive three-year periods. At the end of the third three-year period (year 9), the SCWI or CWI must complete 9-year recertification per QC1 16 — typically additional examination or extensive continuing education credits. CAWIs are not eligible for renewal at all per QC1 15.1; CAWI is a one-time three-year credential intended as a stepping stone to CWI.
ASNT Level II recertification varies by program and employer. Under SNT-TC-1A, the employer's Written Practice typically requires recertification every 5 years — though employer practices vary. Under CP-189 and ASNT central programs, recertification rules are defined by the standard or program directly. Vision examination is required for both AWS and ASNT certifications, typically annually.
Which Should YOU Get? Decision Tree
- You inspect structural welds for AWS D1.1, D1.5, D1.6, or B31.1 work and your role is acceptance/rejection on visual inspection. Get a CWI. The QC1 Part C code-book examination on your code of choice is the highest-leverage credential for that role.
- You perform UT, RT, MT, or PT examinations on welds (or castings, forgings, pressure vessels). Get the ASNT Level II in that specific method. CWI does not authorize you to perform volumetric NDE.
- You do both visual sign-off and volumetric NDE on the same project. Get both. CWI + ASNT UT Level II is the most common combination in fabrication shops.
- You work on ASME pressure vessels predominantly, not AWS structural. Lead with ASNT (UT or RT Level II depending on what your shop runs) — ASME BPVC Section V is the governing reference and prefers ASNT certifications.
- You write NDE procedures or manage other inspectors. ASNT Level III in your primary method is the credential for procedure-writing authority.
- You are early-career and unsure of specialty. CWI first — the broad welding-inspection knowledge base supports any subsequent NDE method specialization. Add ASNT Level II in a single method (often UT or VT) within 1–2 years.
Career Path: From One to the Other
CWI holders frequently add ASNT method certifications — UT Level II is by far the most common second credential, followed by PAUT (phased array ultrasonic testing) endorsement once the 320-hour PAUT experience requirement of D1.1 Annex H4.1 is documented. ASNT-certified inspectors entering welding work commonly add CWI to expand visual-inspection scope and to qualify under D1.1 Clause 8.1.4.2(1) for visual sign-off.
AWS QC1 also defines "Endorsements" per QC1 2.4 — additional knowledge, skill, or ability documented in writing and added to an existing CWI/SCWI credential. Endorsements extend the CWI scope (for example, to specific codes or applications) without crossing into ASNT territory.
Per QC1 9, the AWS Certification Committee approves reciprocity arrangements with welding-inspector certification programs in other countries, so a CWI may have direct value abroad without a separate examination depending on the country.
Related Standards Guides
Frequently Asked Questions
Neither is better — they certify different work. AWS CWI per QC1 certifies welding inspection knowledge specifically (visual inspection, weld discontinuity acceptance, code interpretation per AWS D1.1, D1.5, D1.6, B31.1, etc.). ASNT NDT Level II per SNT-TC-1A or CP-189 certifies a specific NDE method (UT, RT, MT, PT, VT, ET) for general industrial inspection — castings, forgings, pressure vessels, aerospace, welds. Many fabrication shops require both: a CWI for visual weld inspection plus ASNT UT Level II for volumetric weld NDE.
Per AWS QC1, the CWI examination consists of three parts: Part A Fundamentals (150 questions), Part B Practical (40 questions), and Part C Code Book (46 questions). A 72% passing mark is required on each part. Applicants who score a 72% composite average but fail one or more parts may retake the failed parts under the rules in QC1 6.2.5. SCWI applicants take a combined Part A and Part B with a 200-question minimum at the same 72% threshold.
ASNT Level II is a method-specific NDT certification governed by ASNT SNT-TC-1A (Recommended Practice for employer-administered programs) or ANSI/ASNT CP-189 (national standard for centralized exams). A Level II inspector is qualified to set up and calibrate equipment, interpret and evaluate results to applicable codes, organize and report results, and provide on-the-job training to Level I personnel — within the specific NDE method certified (UT, RT, MT, PT, VT, ET, AET, etc.). Each method requires a separate certification.
AWS D1.1:2025 Clause 8.1.4.2 lists five acceptable bases for visual inspection personnel qualification: (1) AWS CWI/SCWI per QC1, (2) CSA W178.2 Level 2 or 3, (3) AWS B5.1 WI/SWI, (4) ASNT NDT Level II VT per SNT-TC-1A or CP-189, or (5) an individual competent by training and experience. So a CWI is the most common path but not the only one. NDT personnel performing UT, MT, PT, or RT are governed separately by Clause 8.14.6 and are exempted from QC1 per Clause 8.14.6.5 — they certify per ASNT SNT-TC-1A, CP-189, or third-party programs (ACCP, ISO 9712).
Yes — many welding inspectors hold both. CWI provides code knowledge and visual inspection authority for AWS-governed work; ASNT method certifications add the volumetric NDE scope (UT, RT, MT, PT) for the same welds or for non-weld inspection. The certifications are administered by separate organizations (AWS for CWI per QC1; ASNT or the employer per SNT-TC-1A) and recertified independently. Career progression in fab and inspection often goes: CWI → ASNT VT/PT/MT Level II → ASNT UT Level II (then PAUT endorsement).
Salary depends on industry, geography, and certification mix more than which single cert you hold. CWIs in structural-steel fabrication tend to earn similar to ASNT Level II inspectors in pressure-vessel work. The combination CWI + ASNT UT Level II commands a premium because it covers both visual and volumetric inspection, eliminating the need for two contractors. ASNT Level III (any method) typically out-earns either single Level II certification due to procedure-writing authority.