EN 10204 Certificate Types Explained: Type 2.1, 2.2, 3.1, and 3.2

What Is EN 10204?

EN 10204 (formally EN 10204:2004, "Metallic products — Types of inspection documents") is the European standard that classifies inspection documents for metallic products into defined types. It establishes a hierarchy of certification levels based on two factors: whether the test results come from specific or non-specific inspection, and who performs and validates the inspection.

Despite being a European standard, EN 10204 is referenced globally. Purchase orders from fabricators in Texas, shipyards in South Korea, and pipeline operators in the Middle East routinely specify "EN 10204 Type 3.1 certificate required." The standard provides a universally understood shorthand for the level of material certification expected — and by extension, the level of confidence in the reported test data.

The standard defines four document types arranged in two groups. Types 2.1 and 2.2 are based on non-specific inspection — the test results come from routine production testing, not necessarily from the specific material being shipped. Types 3.1 and 3.2 are based on specific inspection — the test results are from the actual heat or lot being delivered. The difference is fundamental: non-specific inspection tells you the mill can produce compliant material; specific inspection tells you that the material in front of you is compliant.

What Is a Type 2.1 Declaration of Compliance?

An EN 10204 Type 2.1 document is a declaration of compliance with the order, issued by the manufacturer, without inclusion of any test results. The manufacturer states that the delivered products meet the requirements of the specification, but provides no chemical composition data, no mechanical test values, and no evidence to support the claim.

Type 2.1 is the lowest level of material documentation in the EN 10204 hierarchy. It is essentially a statement of conformity on company letterhead. There is nothing for a quality engineer to verify because no test data is reported. The entire basis for acceptance is trust in the manufacturer’s declaration.

In practice, Type 2.1 is limited to non-critical commercial applications where material properties are not a safety or performance concern. Fasteners, general-purpose structural sections for non-code construction, and commercial-quality bar stock are typical use cases. Type 2.1 is explicitly insufficient for any application governed by ASME BPVC, API specifications, or pressure equipment directives. If your purchase order specifies Type 2.1 for pressure-retaining material, the specification itself is likely wrong.

What Is a Type 2.2 Test Report?

An EN 10204 Type 2.2 document includes test results, but those results are based on non-specific inspection. The manufacturer provides chemical composition and mechanical property data, but the tests were performed as part of routine production quality control — not necessarily on the specific heat or lot being shipped to you.

The practical implication is significant. A Type 2.2 test report for API 5L X65 pipe might show chemistry and tensile data that meets all PSL2 requirements, but those values may come from a different heat than the one stamped on the pipe you received. The data demonstrates that the mill is capable of producing compliant material, but it does not prove that your specific material is compliant.

Type 2.2 is acceptable for some commercial and low-criticality applications where the risk of material non-conformance is tolerable. It is inadequate for any application where heat-specific traceability is required. API 5L, ASTM A106, ASTM A516, and virtually all pressure equipment and pipeline specifications require test results from specific inspection, which means Type 3.1 or Type 3.2. Accepting a Type 2.2 certificate for material ordered to these specifications is a non-conformance, even if the reported values are within limits.

What Is a Type 3.1 Inspection Certificate?

An EN 10204 Type 3.1 inspection certificate is issued by the manufacturer’s authorized inspection representative, who must be independent of the manufacturing department. The certificate includes test results from specific inspection — the chemical analysis and mechanical testing were performed on samples taken from the actual heat or production lot being delivered.

Type 3.1 is the workhorse of industrial material certification. It is the standard requirement for API 5L line pipe (both PSL1 and PSL2), ASTM A106 seamless pipe, ASTM A516 pressure vessel plates, ASME code construction materials (SA-series specifications), and the vast majority of pipeline, pressure equipment, and structural applications. When a purchase order says "MTR required" without specifying a type, Type 3.1 is the generally accepted minimum.

The key characteristics that distinguish Type 3.1 from Type 2.2 are specificity and independence. The test results trace to the actual heat number stamped on the material. The signatory is authorized by the manufacturer but operates independently of the production line. This independence requirement is a quality system control — the person certifying the test results should not be the same person whose production output depends on those results passing.

When reviewing a Type 3.1 certificate, verify that the document identifies the signatory as an authorized inspection representative, that the heat numbers match the material being received, and that all required test results (chemistry, mechanicals, supplementary tests) are present and traceable to the specific heat.

What Is a Type 3.2 Inspection Certificate with Third-Party Validation?

An EN 10204 Type 3.2 inspection certificate carries all the requirements of Type 3.1, plus an additional layer: the inspection and testing must be validated by both the manufacturer’s authorized representative AND either the purchaser’s designated representative or an independent third-party inspection body (such as TUV, Lloyd’s, Bureau Veritas, or DNV).

The dual sign-off requirement is what sets Type 3.2 apart. Two independent parties — one representing the manufacturer, one representing the purchaser or an independent body — must witness the testing, review the results, and sign the certificate. This provides the highest level of confidence that the reported values are accurate and traceable to the specific material.

Type 3.2 is required in the most demanding applications where material failure carries catastrophic consequences:

• •Nuclear construction under ASME BPVC Section III and 10 CFR 50 Appendix B quality assurance programs
• •Subsea and deepwater pipeline projects governed by DNV-ST-F101 or operator-specific specifications
• •Military and defense applications under MIL specifications
• •High-pressure, high-consequence equipment where a single material non-conformance could result in loss of containment

The cost and logistics of Type 3.2 certification are substantially higher than Type 3.1. The purchaser must arrange for a third-party inspector to be present at the mill during testing, which adds scheduling constraints, travel costs, and inspection fees. For this reason, Type 3.2 is specified only when the risk profile justifies the additional assurance.

How Do You Choose the Right EN 10204 Certificate Type?

The required certificate type is determined by the applicable design code, the purchaser’s specification, and the criticality of the application. In most cases, the decision is straightforward because the governing standard or code dictates the minimum requirement.

Type 2.1 is appropriate only for non-critical commercial materials where no design code applies and material properties are not a safety concern. Examples include general-purpose mild steel for non-structural use.

Type 2.2 is acceptable for commercial applications where test data is desired but heat-specific traceability is not required. This is relatively uncommon in industrial practice — most applications that require test data also require that data to be traceable to the specific material.

Type 3.1 is the default for virtually all industrial, pipeline, pressure equipment, and structural applications. API 5L, ASTM specifications, and ASME code construction all require specific inspection with documented, heat-traceable results. If you are unsure which type to specify, Type 3.1 is almost certainly the correct minimum.

Type 3.2 is reserved for the highest-criticality applications where the additional cost and logistics of third-party witnessed inspection are justified by the consequences of material failure. Nuclear, subsea, defense, and high-consequence pressure equipment are typical Type 3.2 applications. When specifying Type 3.2, ensure your procurement documents identify the approved third-party inspection body and define the scope of witnessed testing.

What Are Common EN 10204 Mistakes on Mill Test Reports?

Certificate type not stated or incorrectly stated. Many MTRs include a certification statement but do not explicitly reference EN 10204 or identify the document type. When the purchase order requires "EN 10204 Type 3.1," the certificate should clearly state this classification. An MTR that says "we certify that the material meets the specification" without referencing EN 10204 Type 3.1 is technically ambiguous, and some quality systems will reject it.

Type 3.1 certificate without independent signatory. The defining characteristic of Type 3.1 is that the authorized inspection representative is independent of the manufacturing department. If the certificate is signed only by a production supervisor or a quality control technician who reports to the plant manager, the independence requirement may not be met. The signatory should be identified as an authorized inspection representative per the manufacturer’s quality system.

Accepting Type 2.2 when Type 3.1 is required. This error is more common than it should be. A Type 2.2 document looks similar to a Type 3.1 — both contain chemistry and mechanical test data. The critical difference is whether the test results are from the specific heat being shipped or from routine production testing. If the document does not clearly link the test results to the specific heat number of the delivered material, it may be a Type 2.2 regardless of what it claims to be.

Missing third-party signature on Type 3.2. Type 3.2 requires dual sign-off. A certificate with only the manufacturer’s signature, even if it references "EN 10204 Type 3.2," is incomplete. Both signatures — manufacturer’s authorized representative and third-party inspector — must be present. The third-party inspector’s name, organization, and credentials should be identified on the document.

How Does MTR.AI Validate EN 10204 Certificate Types?

MTR.AI includes EN 10204 certificate type validation as part of its automated compliance check. When processing an MTR, the platform identifies the stated certificate type and verifies that the document content is consistent with the requirements of that type.

For Type 3.1 certificates, MTR.AI verifies that the document includes test results traceable to specific heat numbers, that a certification statement is present, and that an authorized signatory is identified. It cross-references the heat numbers in the certificate against the heat numbers in the material description to ensure traceability. If the purchase order specifies Type 3.1 but the document lacks specific-inspection indicators, MTR.AI flags the discrepancy.

For Type 3.2 certificates, MTR.AI checks for the presence of dual authorization — both the manufacturer’s representative and the third-party inspector. It identifies the third-party inspection body and validates that both signatures are present. Missing third-party validation on a document claiming Type 3.2 status is flagged as a non-conformance.

The certificate type check runs alongside the full chemical and mechanical compliance verification, so quality teams get a complete picture in a single report: are the test values within specification limits, is the certificate type correct, and is the documentation complete? No separate manual checks required.