An anchor arrives with a folder, and the folder has layers. A class rule states what the equipment has to be. A type approval certificate covers a design and the works that make it. Then comes the certificate for the one anchor in front of you, a material certificate for its steel, and the test records behind both. They come from different issuers and are not interchangeable.
UR A1 sets the sizing and load basis and requires anchors to be manufactured in accordance with UR W29, where the testing, marking and certification requirements sit [1][2]. W29's certification requirements then define what the unit document must state (the revision reviewed here is Rev.1, October 2026, which applies to anchors manufactured on or after 1 January 2028) [2].
Only two items belong to your specific anchor: the unit certificate and the marks in its steel. Everything else belongs to a design, a works or a batch. Nothing in the set establishes how the anchor will hold in your berth, or whether it fits your vessel.
The documents in an anchor file
Four layers sit behind a typical pack, each from a different party.
| Layer | Issued or validated by | Covers | Does not establish |
|---|---|---|---|
| Class rule (UR A1, through the society's own rules) | IACS, adopted by the society | Sizing and load basis; manufacture in accordance with UR W29, where testing, marking and certification sit [1][2] | Anything about the anchor delivered |
| Type approval (a Product Design Assessment, usually with a Manufacturing Assessment) | The classification society | A design and the works that produce it, over a model range [3] | That the unit was inspected or certified |
| Unit certificate | The classification society | One anchor: identification, mass, proof loads, test and NDT results, grade, heat treatment, marking applied [2] | Holding performance on a bottom, or fit to the vessel |
| EN 10204 3.1 inspection certificate | The manufacturer's inspection department, independent of production [5] | Starting material against the order, per inspection unit [4] | The anchor's geometry, proof load or performance |
A class rule is not a certificate for a product, and UR A1 defines the anchoring equipment it requires as intended for temporary mooring in a harbour or sheltered area, with certification set against that service [1].
The unit certificate is the only paper that names a single anchor. A 3.1 certificate covers material, not the anchor, and comes from inside the manufacturer's organisation rather than from the classification society [4]. Chain cable is a separate document set, covered in anchor chain grades.
Type approval is a design approval, not a unit inspection
The question that decides how the pack is read is whether type approval means the anchor in front of you was inspected. On the ABS certificate reviewed, it does not.
ABS describes type approval as drawing assessment, prototype testing and assessment of the manufacturer's quality assurance and quality control arrangements; the certificate joins a Manufacturing Assessment of the works to a Product Design Assessment of the design, covers a model range — UA05 to UA360 on the certificate reviewed — not an individual anchor, and does not necessarily waive witnessed inspection or survey procedures [3].
It states its own limits. Unit certification is still required where the anchor is used on an ABS-classed vessel with the Equipment Symbol Circle E notation, so type approval sits above the unit certificate rather than in place of it; that Product Design Assessment was dated 20 January 2017 and ran until 19 January 2022 or until the rules used in it were revised, whichever came first [3].
The classification rule puts it the same way. Holding-power tests are run on anchors whose masses are as far as possible representative of the full range of sizes proposed, so an approval covers a size range rather than every delivered unit; for an HHP size range, at least two sizes are tested, and the largest approved size may not exceed ten times the mass of the largest tested [1].
The HHP designation — at least twice the holding power of an ordinary stockless anchor of the same mass — is approved by full-scale tests, not measured on each delivered anchor [1]. SHHP sits higher and narrower: at least four times the holding power of an ordinary stockless anchor of the same mass, for restricted-service ships, with a mass generally not exceeding 1500 kg [1].
Design, approval and delivered anchor are separated in the note on AC-14 anchors. A type certificate states what was assessed and over what range, not what was done to your unit; a certificate from another society answers the same four questions — what was assessed, over what range, until when, and what remains per unit.
What the unit certificate records
UR W29 requires the anchor to be certified by the classification society, and requires the certificate to state at least the manufacturer, type, mass, proof loads, test results, non-destructive testing results, fluke and shank identification numbers, material grade, heat treatment and the marking applied to the anchor [2].
Read that as a checklist: the identification numbers connect the certificate to the castings, the marking entry to the stamps on the steel, the grade and heat treatment to the material certificates.
The per-unit test behind it is a proof load. Every anchor, at every size, is proof tested to the load in UR A1 Table 2, and that is a proof load, not a working load or a breaking load [1]. The test is also visual: before the load is applied the anchor is examined for harmful surface imperfections, and afterwards for cracks [1].
One detail explains a common mismatch at the desk. UR W29 leaves verification of mass and dimensions to the manufacturer, with the surveyor monitoring, and the anchor mass excludes the swivel unless it is integral [2]. A weighing that includes a separate swivel will not agree with the certificate, and that is not a defect.
Material certificates: 3.1, 3.2, and what they cover
The 3.1 certificate is not the anchor certificate and does not come from the classification society. A 3.1 document states compliance with the order with the results of specific inspection [4], and is validated by the manufacturer's inspection department, independent of production [5]. A 3.2 certificate adds one level of validation, by the purchaser's inspection representative or by an inspection body named in official regulations [5]. The difference between the two is the validating party.
The object is narrower: the inspection unit is usually a heat or a batch [5]. UR W29 handles starting-material certificates separately and requires them to meet the applicable unified requirement; they sit alongside the anchor certificate, not in place of it [2].
A 3.1 certificate therefore carries traceability from steel to anchor. It does not describe geometry or proof load, and says nothing about how the finished anchor will hold. The standard is a paid text, not quoted here; the description follows two published summaries [4][5].
Reading the marks on the anchor
The marks are the only part of the record that is on the anchor itself. UR W29 requires an anchor that meets the requirements to be stamped on the shank and on the fluke, with the shank markings approximately level with the fluke tips [2]. The marking includes at least the mass, the letters HHP or SHHP where the anchor is approved in that category, the society's stamp, the manufacturer's mark and an identification such as the test number or certificate number [2]. Cast shanks and flukes also carry a unique cast identification, cast into the component itself [2].
The elements do different jobs: the society's stamp says whose survey stands behind the anchor, the manufacturer's mark says who made it, and the identification must match a line on the certificate.
Checklist 1 — at the receiving desk:
- Note the identification number and marking entry on the unit certificate.
- Find the shank stamping, at approximately fluke-tip level, and the fluke stamping.
- Compare the stamped mass and any HHP or SHHP letters with the certificate.
- Check the society's stamp against the society named on the certificate.
- Check the manufacturer's mark against the manufacturer named on the certificate.
- Weigh the anchor without a separate swivel before treating a difference as a discrepancy.
Neither half replaces the other: the certificate records the marking applied [2], and the marking carries the identification the certificate cites.
What the certificate does not tell you
Holding power on a given bottom: UR A1 notes that in poor holding ground the holding power of the anchors is significantly reduced [1]. The certificate records a proof load and a category, not a performance figure for your berth.
Design envelope: UR A1 defines that equipment as intended for temporary mooring in a harbour or sheltered area, and states that it is not designed to hold a ship off fully exposed coasts in rough weather or to stop a ship that is moving or drifting [1].
Per-unit performance: the approval behind an HHP or SHHP designation rests on tests of representative sizes, not on a test of your anchor's holding power, and the examination around the proof load is visual [1].
Fit to the vessel is outside the set entirely. Geometry, pocket, hawse pipe and chain-end fit are not what these documents certify, and no entry on a unit certificate addresses them; they are settled against the arrangement drawing and the approval of the installation.
| The certificate shows | The certificate does not show |
|---|---|
| Proof tested to the rule load [1] | How the anchor will hold in a particular seabed [1] |
| Examined for surface imperfections and cracks around that test [1] | That the interior is free of defects [1] |
| Type, mass, identification, grade, heat treatment, marking applied [2] | That holding power was measured on this unit |
| The design was approved as a type, over a size range [1][3] | That the anchor suits the vessel's pocket, hawse pipe or chain end |
What to send before the anchor ships
The best moment to fix a document pack is before the anchor leaves the works.
Five items make a pack checkable:
- The approved drawing and dimension schedule for the size ordered.
- The marks as they will appear, as a photograph or a rubbing of the stampings.
- The vessel's class notation, including any Equipment Symbol such as Circle E.
- The project specification clause naming the documents required at delivery.
- Written confirmation of which documents will be issued, by which party, against which rule revision.
The first four compare the delivered unit with the order; the fifth fixes who owes which paper.
If you are checking a pack against an anchor, send the drawing, the marks as a photograph or rubbing, the class notation and the project specification through the contact page, so the set can be read against the actual unit.
References
[1] IACS, UR A1 — Anchoring Equipment, Rev.7 2020/Corr.1 2021 — https://ww2.eagle.org/content/dam/eagle/regulatory-news/2022/IACS-UR-A1.pdf
[2] IACS, UR W29 — Requirements for manufacture of anchors, Rev.1 Oct 2026 — https://www.classnk.or.jp/hp/pdf/info_service/iacs_ur_and_ui/ur_w29_rev.1_oct_2026_ul.pdf
[3] ABS, Confirmation of Product Type Approval 17-IS1595785-PDA (manufacturer-hosted sample) — https://www.ultramarine-anchors.com/data/filemanager-upload/certificates/ABS%20Certificate_untill%202022.pdf
[4] Dillinger, Types of inspection documents according to EN 10204:2004, Rev.1 Oct 2018 — https://en.dillinger.de/app/uploads/2024/03/20181102114837-KI_EN10204_rev1_e.pdf
[5] Zickwolff, EN 10204 explained — https://www.zickwolff.de/wissen/en/certificates-en-10204/
