Quick answer
A steel mill test certificate links material identification to inspection results and the applicable order requirements. Under EN 10204, type 3.1 is validated by the manufacturer’s authorized inspection representative, independent of the manufacturing department. Type 3.2 adds validation by the purchaser’s authorized inspection representative or an inspector designated by official regulations. The certificate type does not define the steel grade or its required properties. [1]
Begin with identity before checking results
An impressive tensile result is irrelevant if the certificate cannot be linked to the material received. Start by comparing the manufacturer, grade, heat number and product description with the purchase order, packing list and physical markings.
For a mixed shipment, check the mapping between each heat and its material. If a bundle contains multiple heats, the receiving team needs a clear way to identify them. Preserve that mapping when stock is cut, moved to a different rack or issued to production. Otherwise, a correct original certificate can become disconnected from the part eventually manufactured.
Inspection certificate types compared
| Inspection document | Type 3.1 | Type 3.2 |
| Main content | Compliance statement and results of specific inspection | Compliance statement and results of specific inspection |
| Manufacturer validation | Authorized inspection representative independent of manufacturing | Authorized inspection representative independent of manufacturing |
| Additional validation | Outside inspection is not required by the document type alone | Purchaser’s authorized representative or inspector designated by official regulations |
| Planning requirement | Agree required results and traceability in the order | Also agree inspection participation and certification arrangements |
The extra validation does not make type 3.2 a different steel grade. A type 3.1 document can relate to material that meets the same product requirements; the difference concerns inspection-document validation. Select the required type from the contract and applicable specification. [1]
Read the certificate in a consistent order
Use the following sequence for incoming material review. The fields are illustrative review categories, not a sample KSL certificate.
| Certificate field | Buyer review | Question to resolve if unclear |
| Manufacturer and document identity | Confirm who issued the record | Is this the original document or a traceable copy |
| Grade and product specification | Match the order and agreed edition | Has a substitution been approved |
| Heat number and product form | Match the delivered material | Which pieces are covered by this certificate |
| Chemical analysis | Compare required elements with specified limits | Is the result heat analysis or product analysis |
| Mechanical test results | Check values, units and sample details | What material condition and sample location were tested |
| Treatment condition | Match the ordered supply condition | Was the test made in the delivered or another defined condition |
| Additional inspection records | Locate required reports | Are UT and other agreed inspections traceable to this delivery |
| Validation | Check the authorized validation for the required type | Is the document complete for the contract |
This approach helps receiving teams identify specific discrepancies rather than accept or reject a document based on appearance.
Separate heat analysis from mechanical test condition
Chemical analysis records the material composition. Mechanical test results describe the tested sample in its documented condition. Review both against the governing product specification rather than comparing every order to one generic online property table.
This is especially important for ingots and billets intended for further processing. Ask whether a mechanical result comes from a separately treated test sample or represents a defined delivered product condition. Further forging and heat treatment may require their own acceptance evidence. A certificate for starting steel does not automatically certify the finished component.
Plan independent inspection early
Agree the required inspector involvement before manufacture and testing. LRQA explains that genuine type 3.2 certification involves verification of material traceability and properties, with inspection and witnessing appropriate to the requirements. A paperwork review or a laboratory report simply relabelled “3.2” does not establish the same certification. [2]
Where material is purchased through a stockist, clarify whether the proposed certification is fully in accordance with type 3.2 or described as meeting its intent. Obtain the purchaser’s acceptance of the proposed route before work begins. The wording and inspection scope should be clear in the quotation. [2]
Resolve discrepancies before issuing material
If the order requires a test that is absent, ask for the traceable report or an agreed resolution. If the heat marking differs from the certificate, investigate the identity mismatch before release. Avoid accepting a manually changed certificate without clarification from the issuer.
Keep the original record and any corrected revision together with the resolution correspondence. A short receiving checklist is useful, but it should point reviewers to the contract-specific requirements rather than assume every steel delivery needs identical tests.
Frequently asked questions
Does EN 10204 specify the chemical composition of steel
No. It concerns inspection documents. The steel grade, product standard and purchase specification define the material requirements.
Is outside inspection required for every certificate
Type 3.1 is validated by the manufacturer’s authorized inspection representative who is independent of manufacturing. Outside inspection is not automatically part of type 3.1; type 3.2 requires additional validation as described above.
Can a laboratory report replace the specified inspection certificate
A test report may support certification, but it does not independently fulfil all type 3.2 validation and traceability requirements. Confirm the certification route with the purchaser and appointed inspection party.
Does one certificate cover every piece in a shipment
Only the material identifiable within its stated scope. Multiple heats or product batches may require several records and a delivery mapping.
Discuss inspection documentation with KSL
KSL’s product pages describe heat-number marking, while its Testing Technology page lists available test facilities. Share the required certificate type, product specification and inspection plan through the KSL enquiry page. Confirm the agreed documentation scope with the quotation. [3, 4]