EN 10204 3.1 vs 3.2: Certificate Differences, Use Cases & Checklist

EN 10204 defines inspection certificates for metallic products. A 3.1 certificate is issued by the manufacturer’s authorized inspection representative with heat/batch test results and a statement of conformity. A 3.2 certificate adds independent validation by the buyer’s inspector and/or an officially designated body, when required by the PO/project spec—no ad-hoc values.

New to materials & MTCs? Start with the structured course: Raw Material Inspection Training. For hands-on certificate reading, see the MTC Interpretation Guide.

What you’ll get in this guide:

• EN 10204 explained (what certificates cover, who signs)
• 3.1 vs 3.2 — clear differences and when to specify 3.2
• How to verify an MTC (step-by-step checklist)
• Red flags & fixes for receiving inspection
• A printable checklist (PDF) you can use on the shop floor

 

EN 10204: What the Inspection Certificate Standard Covers

• Scope: standardizes inspection certificates / MTCs supplied with plates, bars, forgings, and castings.

EN10204 covers metallic material such as plates, bars, forgings, and castings.

 

• Purpose: state conformity to the order and list test results (chemical, mechanical, impact/hardness, and NDE where applicable) as required by the project spec.
• Who issues/signs: depends on certificate type (3.1 vs 3.2).
• Acceptance language: always write “as per the standard/edition referenced by the project spec.” Never invent numeric limits.

 

EN 10204 3.1 vs 3.2 — Core Difference (at a glance)

3.1 certificate (manufacturer-issued)

• Signed by the manufacturer’s authorized inspection representative (independent of production).
• Includes heat/batch test results and a statement of conformity to the order.
• Independence: internal to manufacturer; labs/procedures traceable per spec.

3.2 certificate (with independent validation)

• Signed by the manufacturer and a buyer’s authorized inspector and/or an officially designated body (as your PO/spec requires).
• Same results as 3.1 plus external/official verification/witnessing where specified.
• Use when risk/regulation or client mandate demands third-party/authority oversight.

Side-by-Side Comparison

Topic	EN 10204 3.1	EN 10204 3.2
Signatory	Manufacturer’s authorized inspection representative	Manufacturer + buyer’s inspector and/or officially designated body
Independence	Internal	External/official participation
Evidence	Heat/batch test results; conformity to order	Same results with independent validation/witness (as ordered)
Typical use	Standard criticality, proven mill/vendor	High-risk service, regulatory/authority or client requirement
Cost/lead time	Lower	Higher (coordination, witnessing, stamps)
Acceptance	Per PO/project spec & referenced standards	Per PO/project spec & referenced standards

Practical rule: don’t try to “upgrade” a 3.1 to 3.2 after the fact. Define the required type in the PO/ITP from day one.

 

When to Specify EN 10204 3.2 (decision cues)

• Regulatory/authority oversight applies (jurisdictional pressure equipment, critical service).
• Client specification calls for 3.2 or third-party witnessing.
• High risk profile: sour service, H₂S exposure, high design P/T, severe consequence of failure.
• New/unproven mill/vendor where independent validation reduces risk.
• PO wording (example): “Certificate type: EN 10204 3.2, as required by the project spec/ITP.”

 

How to Verify an EN 10204 3.1 / 3.2 Certificate (checklist)

Receiving Checklist (copy/paste)

Item	What to verify	Result
PO & item match	PO number, line item, product form/grade, quantity align with delivery	☐
Heat numbers	Heat/batch numbers present and traceable to delivered items	☐
Test results present	Chemical, mechanical, impact/hardness, NDE (if applicable) included as required by the project	☐
Standard references	Procedures/tests cite the correct standard & edition (per project spec)	☐
Signatures/stamps	3.1: manufacturer’s authorized rep signed. 3.2: manufacturer + buyer’s inspector and/or official body signed (as ordered)	☐
Lab & calibration	Test lab identity and calibration/competence referenced per project procedure	☐
Traceability map	Certificate lines link to delivery note and item/tag/serial list	☐
Corrections	Any corrections are controlled (reissue/versioning), not hand-amended	☐
Acceptance phrasing	“Accepted as per <standard/edition> referenced by the project spec.” No ad-hoc values	☐

Rolling this into your ITP? Add a W/H point for certificate review and reference it in the FAT/receiving stage: Vendor Inspection ITP Template.

 

Traceability & Required Content on MTCs (keep it audit-ready)

What must be on an EN 10204 certificate (3.1 or 3.2):

• PO & line item, manufacturer name/site, product form/grade, dimensions/quantity.
• Heat/batch numbers and clear heat → lot → piece mapping for the delivered items.
• Test results required by the order (chemical, mechanical, impact/hardness, NDE where applicable) with method references.
• Referenced standards & editions used in testing/procedures (as named by the project spec).
• Signatures/stamps: 3.1 = manufacturer’s authorized inspection representative; 3.2 = manufacturer and buyer’s inspector and/or officially designated body (as ordered).
• Document control: issue date, certificate ID/revision, page count, attachments list.

How to maintain traceability (simple and defensible):

• Cross-reference each MTC line to the delivery note, packing list, and tag/serial list.
• Keep a heat map: heat → plates/bars/forgings → finished parts → tag/serials.
• Use a naming rule for files/photos: PO-Item-Tag-DocType-Seq (e.g., 450123-V001-MTC-01.pdf).
• In your dossier index, show where each heat appears in the final assembly or lot.

 

Common Red Flags & How to Fix Them (fast triage)

Red flag	Why it matters	Fix (acceptance phrasing preserved)
Heat numbers on MTC don’t match delivery/tags	Breaks traceability	Request corrected MTC; re-map heat → items; update dossier index.
Missing 3.2 signatory/stamp when ordered	Certificate type not satisfied	Have buyer’s inspector/official body sign as per order/ITP or reissue certificate.
Partial test results or wrong edition cited	Acceptance basis unclear	Re-test or re-document as per the standard/edition referenced by the project spec.
Handwritten edits on a signed MTC	Document control at risk	Reject edits; request reissued certificate with proper revision history.
Lab identity/calibration not referenced	Evidence credibility weak	Add lab accreditation/calibration references per project procedure; attach certs.
Mixed heats on one line item	Ambiguous mapping	Split MTC lines per heat/batch; update packing/delivery and tag list.

Rule: do not invent numeric limits. Always write: “Accepted as per <standard/edition> referenced by the project spec.”

 

FAQs — EN 10204 3.1 vs 3.2 (snippet-ready)

What is EN 10204?
A standard that defines inspection certificate types for metallic products. Certificates declare conformity to the order and list test results required by the project spec.

What’s the difference between 3.1 and 3.2?
3.1 is issued by the manufacturer’s authorized inspection representative. 3.2 adds independent validation by the buyer’s inspector and/or an officially designated body, as required by the order.

Who can sign a 3.2 certificate?
The manufacturer plus the buyer’s authorized inspector and/or an officially designated body—exact signatories follow the PO/ITP.

Is 3.2 always required?
No. Use 3.2 when the project spec demands third-party/official oversight or the risk profile/regulations justify it.

Can a 3.1 be “upgraded” to 3.2 later?
Not without the buyer’s written approval and proper witnessing/signature as per the order/ITP. Define the required type at PO placement.

What must appear on a Material Test Certificate (MTC)?
PO, item, product details, heat numbers, test results, referenced standards/editions, signatures/stamps, and controlled revision/attachments.

How should I file certificates in the vendor dossier?
Map heat → items → tag/serials, store MTCs with delivery/packing, and list them in the dossier index. Acceptance wording stays as per the standard/edition referenced.

 

Download: 3.1 vs 3.2 Verification Checklist (PDF)

Filename: EN10204_3.1_vs_3.2_Checklist.pdf

• Side-by-side cues for 3.1 vs 3.2 signatories and independence levels.
• Receiving checklist: PO match, heat mapping, test results, standards/editions, stamps, lab/calibration.
• Traceability map fields to tie heat → lot → tag/serial and the dossier index.

CTA: Download the 3.1 vs 3.2 Verification Checklist (PDF) and use it on your next receiving inspection.

 

Where to Go Next

Raw Material Inspection — Training

Build a repeatable receiving & approval workflow for MTCs and EN 10204 certificates. Join Raw Material Inspection Training — risk-based checks, traceability mapping, and acceptance phrasing as per the standards your projects reference.

Deep-dive on reading certificates: MTC Interpretation Guide

Plan how certificates show up in inspection points: Vendor Inspection ITP Template