Does AWS D1.1 accept an ISO 9606-1 or EN 287-1 welder qualification certificate?

No. AWS D1.1 requires welders to qualify under its own Clause 6 provisions. An ISO 9606-1 certificate demonstrates welding skill but does not substitute for a WPQ test performed and documented per AWS D1.1 requirements. The welder must run a qualification coupon per the applicable AWS D1.1 tables.

Can an ISO 9606 certificate be used as supporting evidence to waive the AWS D1.1 WPQ test?

Not under the standard code. AWS D1.1 has no provision for accepting foreign or third-party qualification certificates in lieu of a WPQ test. Some owner or project specifications may grant credit for prior AWS WPQ tests from another employer, but this is specific to AWS-based qualifications, not ISO 9606.

How long does a new WPQ test take for a welder who already has practical experience?

For a single process and position, a WPQ coupon can be welded in one to two hours by an experienced welder. Testing, inspection, and documentation (bend tests or radiograph, as applicable) typically add one to three days. A welder with prior experience usually qualifies on the first attempt.

Does a welder who passed an AWS D1.1 WPQ in another country or with a foreign employer need to retest in the U.S.?

An AWS D1.1 WPQ is generally portable between employers and jurisdictions when the welder has maintained continuity of welding in the same process and position group. The receiving employer reviews the prior WPQ documentation; if it is current and the process/position coverage is adequate, no retest is needed under the code. Foreign ISO qualifications are not portable in this way.

ISO 9606 and Foreign Welder Qualifications Under AWS D1.1

ISO 9606-1 and EN 287-1 welder certificates don't satisfy AWS D1.1 WPQ requirements. Learn the compliant path for qualifying welders with international credentials on U.S. structural projects.

Fabrication shops working with international workforces regularly encounter the same question: a skilled welder arrives with a European or international qualification certificate — an ISO 9606-1 for structural steel butt welds, or an EN 287-1 (now largely superseded) for a combination of process and position — and the shop wants to put that welder on structural production immediately. The certificate looks credible. The welder has clearly been tested. Can the shop accept the credential and move on?

Under AWS D1.1, the answer is no. The code has its own qualification system, and it does not cross-reference or accept international qualification standards as equivalent. This is not because ISO 9606-1 is a weak standard — it's a rigorous international benchmark — but because AWS D1.1 qualification tests are designed to verify that a welder can follow a specific WPS, not just demonstrate generic welding skill.

What ISO 9606-1 Tests and What It Doesn't

ISO 9606-1:2012 (Qualification testing of welders — Fusion welding — Part 1: Steels) is the current international standard for welder qualification in steelwork. A certificate under this standard documents the welder's demonstrated ability to produce sound welds in a specific material group, process, filler type, joint configuration, position, and plate or pipe thickness range.

The ISO 9606-1 certificate is competence-based: it tells you the welder can produce a weld that meets radiographic or mechanical test acceptance criteria in the tested conditions. What it does not tell you is that the welder can operate within the specific parameter constraints of an AWS D1.1 WPS — the travel speed range, interpass temperature limit, electrode heat code, and heat input ceiling documented on the procedure.

AWS D1.1 WPQ testing addresses this directly. The welder qualifies on a specific WPS (or a range of WPS represented by the qualification test) and demonstrates the ability to produce code-compliant welds following that procedure's documented parameters. The WPQ record links welder identity to a specific process, position, and WPS scope — which is the traceability a structural inspector or auditor needs.

The AWS D1.1 WPQ Framework

Under AWS D1.1, welder performance qualification is governed by the code's qualification clause. A welder qualifies by welding a test coupon in the required position and joint configuration, using a WPS as the guide. The resulting coupon is evaluated by:

Visual inspection to confirm surface quality and profile meet the code.
Bend testing (face and root bends) to check fusion and ductility — the standard mechanical test for most structural WPQ.
Radiographic testing as an alternative to bend testing for certain joint configurations and thicknesses.

The qualification scope covers a defined range of positions, thicknesses, and processes. A welder who qualifies with a 3/8 in. plate groove weld in the 2G (horizontal) position qualifies for a range of groove and fillet weld positions and thicknesses as defined by the code's qualification extent tables. A separate test is required if the welder needs to qualify for overhead position (4G/4F) or vertical upward progression when those were not covered in the initial test.

The CWI responsible for qualification must witness the WPQ test and sign the qualification record. The documentation must identify the welder, the WPS used, the test date, the position tested, the coupon dimensions, and the test results. This record stays with the welder and moves with them to new employers — provided the welder maintains continuity of welding in the qualified process and position, as required by the six-month continuity rule.

Why the Six-Month Rule Applies Equally to Foreign-Credentialed Welders

Once a welder has obtained an AWS D1.1 WPQ, the six-month continuity requirement under the qualification clause applies regardless of the welder's background. A welder who holds both an ISO 9606-1 certificate and an AWS D1.1 WPQ must still maintain continuity under the AWS standard — demonstrated by an employer attestation that the welder has performed welding in the qualified process within the preceding six months. The ISO 9606-1 certificate does not extend or reset the AWS continuity clock.

A welder who lets their AWS D1.1 WPQ lapse must retest — even if their ISO 9606-1 is current and they have been welding continuously under a European standard. The two qualification systems are independent.

For a detailed look at how the continuity rule works and how shops track it, see AWS D1.1 welder continuity and the six-month lapse rule and welder continuity tracking for multi-shift shops.

Practical Path for Qualifying Welders with International Credentials

The process for putting an ISO-credentialed welder to work on AWS D1.1 structural production has three steps: assess their existing credential for scope, run the AWS WPQ test, and document the results per the code.

Step 1: Assess the ISO 9606-1 scope for orientation. The ISO certificate will indicate the process (SMAW, GMAW, GTAW, FCAW), the material group (Group 1 = unalloyed and fine-grain steels, roughly equivalent to structural carbon steel), the joint type (BW = butt weld, FW = fillet weld), and the position and thickness range tested. This tells the shop what positions and processes to prioritize for the AWS WPQ — if the welder's ISO scope covers flat and horizontal butt welds, start with a 1G or 2G AWS test to establish baseline coverage quickly, then add 3G and 4G if the work requires it.

Step 2: Assign a WPS for the qualification coupon. The welder qualifies by welding to a specific WPS. Select a WPS that covers the range of production work the welder will perform — process, base metal, and position. A prequalified WPS under Clause 5 is perfectly valid for this purpose. The welder does not need to know the WPS by memory, but they must follow its documented parameters during the test.

Step 3: Witness, test, and document. The CWI witnesses the test coupon, evaluates it visually, submits the bends or film per the code requirements, and completes the WPQ record. Most experienced structural welders with sound ISO credentials pass on the first attempt. The documentation is completed the same day the test is welded; bend test results are available within hours from most independent test labs.

Total elapsed time from test coupon to a qualified welder on production is typically two to three days, accounting for lab turnaround. For shops with multiple welders to qualify, testing can be batched — multiple welders can run qualification coupons simultaneously under a single CWI witness session.

Common Documentation Errors to Avoid

Several documentation errors appear frequently when qualifying foreign-credentialed welders for the first time on an AWS D1.1 project:

Using the ISO certificate as the WPQ record. Some shops attempt to file an ISO 9606-1 certificate in the welder qualification file as evidence of AWS qualification. This does not satisfy the code and will be flagged by a third-party auditor or special inspector. The AWS D1.1 WPQ record form — or an equivalent form capturing all required data elements — must be completed for every welder.

Omitting the WPS reference on the WPQ record. The qualification record must identify the WPS used during the test. A WPQ with "field settings" or no WPS reference cannot be tied to a qualification scope and is not defensible during an audit.

Assuming the welder's process covered by ISO matches the process classification under AWS. ISO 9606-1 uses ISO process designations (111 = SMAW, 135 = GMAW, 136 = FCAW with flux-cored wire, 141 = GTAW). AWS D1.1 uses AWS process designations. These do not always correspond one-to-one; FCAW in particular has gas-shielded (FCAW-G) and self-shielded (FCAW-S) variants under AWS that affect WPS and WPQ scope differently. Confirm the actual process variant before assigning the WPS for the qualification test.

Failing to record the welder identification number consistently. The welder's ID or stamp number used on the WPQ record must match the ID used on production weld maps and traveler documents. International welders may have worked under different employer ID systems; establish a consistent shop identifier before the WPQ test and use it on all subsequent records.

What Owner and AHJ Review Will Look For

On projects subject to special inspection (IBC Chapter 17) or third-party verification, the inspector will request WPQ records for all welders on the project. A well-maintained WPQ file for a foreign-credentialed welder looks identical to one for any other welder: an AWS D1.1 WPQ form, a bend test report or RT film, and an employer continuity attestation if more than three months have passed since the test.

The ISO 9606-1 certificate can be included in the file as background, but it is context — not qualification evidence under AWS D1.1. Explaining this to inspectors or owners before they ask saves time during the documentation review phase.

The WPQ qualification tracking tools on this platform let you maintain a complete digital welder file — including qualification scope, test dates, continuity attestations, and expiration alerts — so nothing slips through when a project owner requests full documentation on short notice. See also welder WPQ portability between fab shops for the code basis for transferring existing AWS qualifications between employers.