Checklist: Forging NDT Lab Qualification Criteria

Why Verify Lab Qualification Before Commissioning

A third-party laboratory can fail a perfectly sound forging if its testing setup is out of calibration or if the inspector does not hold the right certification. The risk is not just a rejected part. It is a delayed delivery, a costly rework cycle, or a flawed part that reaches the customer. Before sending a forged flange, shaft, or housing for testing, a buyer needs a clear picture of the lab’s capability. The checklist below is designed for that moment. It groups the verification into five practical themes. Use it as an audit tool. Print it, send it to the lab, or use it to compare two or three bidders.

Does the Lab Hold Valid Lab Accreditation?

Accreditation is the first line of defense. It means an independent body has reviewed the lab’s procedures, management, and technical competence against a recognized standard. A certificate is not enough. The buyer must confirm that the scope of the accreditation actually covers the work being requested.

A lab may be accredited for magnetic particle testing but not for phased array ultrasonics. It may cover carbon steel but exclude stainless or titanium. The scope statement in the certificate is the legal basis for the lab’s claims. If the job falls outside the accredited scope, the lab can still perform the work, but it cannot claim the results under that accreditation. The buyer must decide if that is acceptable.

Checklist items:

1. Request a copy of the current accreditation certificate.
2. Confirm the certificate is from a recognized national or international body.
3. Verify the accreditation scope includes the specific NDT method required.
4. Confirm the scope covers the material type, for example carbon steel, alloy steel, or stainless steel.
5. Check the validity dates and confirm the accreditation is not expired.

Red flags:

• The lab refuses to provide the certificate or scope statement.
• The accreditation is for a different facility than the one performing the test.
• The scope lists a method, but the lab says it is only “familiar” with it.

Are Inspection Personnel Properly Certified?

A lab’s reputation is only as strong as the person holding the probe or reading the film. Certification is the minimum standard. It proves the inspector has passed a written exam and a practical skills test. The level of certification matters. A Level I inspector can perform a basic test. A Level III inspector can interpret complex results and approve procedures. For critical forgings, the buyer should require a Level II or Level III inspector for the final evaluation.

Certification is method-specific. A certified ultrasonic inspector is not automatically certified for radiographic testing. The buyer must match the inspector’s certification to the specific test required. For a forged turbine disk, a Level III ultrasonic inspector is standard. For a simple magnetic particle check on a low-carbon steel shaft, a Level I may suffice, but the contract should state who is responsible for the final acceptance decision.

Checklist items:

1. Ask for the certification IDs of the inspectors who will perform the test.
2. Verify the certification level matches the complexity of the job.
3. Confirm the certification is current and not expired.
4. Ask if the inspector has prior experience with the specific part geometry and material.
5. Request a list of the inspector’s certifications for all methods in the contract.

Red flags:

• The lab uses a Level I inspector to interpret complex ultrasonic findings.
• The inspector’s certification covers a different material or technique than the job requires.
• The lab cannot provide the inspector’s name until after the work is done.

Is the Equipment Calibrated and Maintained?

NDT equipment is sensitive to drift. An ultrasonic transducer can lose sensitivity over time. A radiographic source can degrade. A magnetic particle system can lose its field strength. Calibration is the process of verifying that the equipment produces the expected output. Without current calibration, the results are meaningless.

The buyer should ask for calibration certificates that are traceable to national standards. These certificates should show the last calibration date, the next due date, and the reference standard used. For phased array systems, the buyer should verify that the reference blocks are of the correct material and geometry. For radiography, the source output and film response should be checked. For eddy current, the probe compensation should be verified against a reference standard.

Checklist items:

1. Request calibration certificates for all equipment that will be used.
2. Confirm the calibration dates are current and within the required interval.
3. Verify the calibration is traceable to national or international standards.
4. Ask if the lab performs in-house calibration or uses an external service.
5. For phased array and ultrasonic tests, confirm the reference blocks are appropriate.

Red flags:

• Calibration certificates are missing or older than the required interval.
• The lab cannot explain what the calibration verifies.
• The equipment is shared among multiple labs and is not always on site.

Do the Inspection Standards Match the Contract?

Every job has a standard. It may be a customer-specific specification, a national standard, or an international standard. The lab must use the exact standard required by the contract. A mismatch here is a common source of disputes. The standard defines the acceptance criteria, the test parameters, and the reporting requirements.

For example, a flange may require testing per a specific radiographic standard for ASME pressure vessels. A different standard may be used for a non-pressure part. The acceptance criteria can vary significantly between standards. A flaw that is acceptable under one standard may be rejected under another. The buyer must ensure the lab is using the correct standard and that the inspector is familiar with it.

Checklist items:

1. Confirm the lab uses the exact standard specified in the contract.
2. Verify the inspector has experience with that specific standard.
3. Ask for a sample report from a similar job to review the format.
4. Confirm the lab understands the acceptance criteria for the specific part.
5. Check if the lab has a procedure for handling deviations from the standard.

Red flags:

• The lab suggests a different standard without being asked.
• The inspector is unfamiliar with the specific standard required.
• The sample report does not match the format required by the contract.

How Does the Lab Handle Reporting and Traceability?

The report is the final product. It is the document that proves the part passed. A good report is clear, complete, and traceable. It should identify the part, the material, the test method, the standard used, the inspector, and the date of the test. It should include all relevant images, such as radiographs or ultrasonic A-scan traces. For ultrasonic testing, the report should include the depth and location of any indications.

The buyer should review the report template before the work starts. This saves time later. If the report is missing a required field, the lab must correct it. If the report is ambiguous, the buyer may need to reject it. The lab should have a quality control process that reviews the report before it is issued. This second pair of eyes catches mistakes that the inspector, focused on the test, might miss.

Checklist items:

1. Request a sample report from a similar job.
2. Confirm the report includes all required fields: part ID, material, method, standard, inspector, date.
3. Verify the report includes all relevant images or data.
4. Ask about the lab’s quality control process for reports.
5. Confirm the lab can provide a digital copy in the required format.

Red flags:

• The sample report is missing required information.
• The report is ambiguous or uses non-standard terminology.
• The lab has no quality control step for the final report.

Audit Table: Quick Reference

Theme	Key Question	Red Flag
Accreditation	Does the scope cover the method and material?	Scope does not match the job requirements.
Personnel	Is the inspector certified for this specific test?	Inspector is not certified for the method or material.
Equipment	Are calibration records current and traceable?	Calibration is expired or not traceable.
Standards	Does the lab use the exact contract standard?	Lab suggests a different standard.
Reporting	Does the report meet the contract format?	Report is missing required fields or images.

Final Audit Step: The Mock Test

The final step is a mock test. Send a known good part to the lab for a test. This part should be a simple forging, such as a small bar of the same material as the production part. The lab should perform the full test and issue a report. Review the report. Check the calibration dates. Verify the inspector’s certification. Confirm the standard used. This mock test costs very little. It reveals problems that a paper audit might miss. If the lab fails the mock test, do not commission the production work.