Operational guide · Certification & surveys

Survey in Dry Dock

A dry-dock survey connects items to examine, preparation, evidence and acceptance. Classification and statutory certification have their own scopes and authorities; follow-up remains open until findings, repairs and documents are reconciled.

special surveyrenewal surveyclass

Operational Explanation

Dry dock provides access and coordination, rather than one single survey type. A bottom inspection examines the underwater hull and related items; a class Special Survey or statutory renewal may include other spaces, systems and tests. The scope needs to identify which survey items are out of water, which are elsewhere and what evidence is required.

The surveyor examines condition and results under the survey’s mandate. The same organisation may act for class and, where authorised, for the flag: identify the role in each report. Yard and suppliers carry out work or services; their statements and measurements support assessment without replacing acceptance.

For the bottom, hull condition, appendages, sea connections and external fittings form a set of items to prepare, not an order to dismantle everything. Access, cleaning, resources and openings must allow the agreed examination safely. IACS Z3 Rev.8, 3.2.

Regulatory Reference

The statutory framework comes from the relevant Conventions and HSSC Survey Guidelines 2025 — A.1207(34); class scope from the applicable Rules. UR Z17 governs service suppliers within its fields, not the whole survey.

UR Z17 governs service suppliers: it does not by itself define the entire Special Survey scope. The IACS page distinguishes current Rev.21 from future Rev.22/23 from 2027/2028. Check the supplier’s certificate, authorised activity and conditions before commissioning work; its report remains subject to the acceptance required for the survey. IACS UR Z17: current and future versions.

At docking close-out collect reports, measurements and tests, repair outcomes and updated documents. Reconcile class status and statutory certificates separately against outstanding items: a paid invoice or yard declaration that work is complete does not equal survey completion. IMO: surveys and certification.

HSSC General 2 distinguishes survey types and General 3 delimits application; General 4.7–4.8 connects repairs, unsatisfactory outcomes, corrections and conditions. Docking does not make every item applicable to every ship. Statutory verification belongs to the Administration, nominated surveyor or organisation authorised for that role. HSSC General 2–4.8; IMO: verification mandate.

Scope of Application

Study and familiarisation with surveys coordinated during docking: bottom/docking surveys, parts of Special Surveys and statutory surveys actually planned. Identify the ship, certificate or class status concerned, survey type, items and limits. Not every survey is a bottom inspection and not every service has the same supplier-approval requirement.

For Z17 distinguish activity, supplier-certificate conditions and Society Rules: approval does not extend by analogy to any service or make. Ship/yard procedures, competent personnel and survey requirements still govern access, preparation and tests.

Procedure / How to Complete It

Identify scope. Read status and programme, distinguish class and statutory certificate, and agree items, methods, attendance and evidence with the competent party.
Prepare access and information. Link drawings, changes, previous reports and defects with areas to examine. Plan cleaning, access arrangements, isolations and relevant permits: this card alone authorises no opening or test.
Check services. Where measurements or specialist work are needed, verify approval for that service, personnel, equipment and reporting format. For UTM agree the programme and results required; one isolated value does not establish overall structural condition.
Follow examination and findings. Make area/component, method, observations, measurements and decision identifiable. Agree defect follow-up and the hold point before work prevents examination.
Connect repair and verification. Record actual work and prescribed post-intervention checks. The competent party decides credit and acceptance within its scope; a test is not passed merely because it was performed.
Reconcile completion. Distinguish technical report, survey status, conditions or recommendations, endorsements and certificates. Hand outstanding items to the ship with assigned due dates and follow-up; update relevant maintenance and documentation.

Practical Example

Teaching scenario: a cargo ship coordinates a bottom inspection and work connected to its Special Survey in dock. Examination finds a sea-valve defect; the report identifies equipment and follow-up. Before prescribed closure, repair and verification by the competent surveyor are linked. The team records class and statutory-survey status separately: the yard completing work does not automatically renew every certificate. Any UTM service retains approval, measured areas and its report within the relevant scope.

What Typically Goes Wrong

Access may be closed or a surface coated before inspection; a report may not identify the component or measured area. Even “renewal” can hide which certificate or status is being updated. Without the link between finding, intervention, verification and acceptance, docking can end with a survey or condition still open.

Common Mistakes Mistake Library

Mistake	Consequence	How to Avoid It
Treating Special Survey and statutory renewals as one acceptance	A certificate or condition may remain unverified	Identify survey, items and the role accepting its outcome
Using a supplier approved for a different activity	Measurements or services may be unacceptable for the survey	Check scope, limits, personnel and the relevant certificate
Closing access or coating before the hold point	Verification may require reopening or repeating work	Agree attendance and hold points in the programme
Treating repair or a report as survey completion	Credit, conditions or documents remain outstanding	Reconcile verification, acceptance and final status within the required scope

What the PSCO Checks

Check certificates and endorsements, survey outcomes, residual defects and actual condition. Yard and supplier reports support the evidence but do not replace acceptance by class or the competent Administration/RO.

Keep finding follow-up explainable and applicable documents available. Inspection depends on its regime and facts; commercial docking close-out is not a new PSCO approval. IMO: certificates and inspection.

Operational Tips

Use the same area/equipment identifiers in worklists, measurements, reports and repairs.
Distinguish class role and statutory mandate even when the same organisation attends.
Plan hold points and services before an area becomes inaccessible.
Hand over outcome, conditions and updated documents with outstanding items, rather than only a bundle of reports.

Preparation checklist

Scope of each survey and accepting role identified
Items, drawings, changes and previous reports identifiable
Safe access and preparation agreed in the programme
Service supplier and applicable scope/version checked where required
Measurements, findings, repairs and subsequent checks connected
Class status and statutory documents reconciled separately
Outstanding items, assigned due dates and follow-up handed to the ship

FAQ

Does one Renewal renew class and statutory together?

No. Class and statutory certification have separate scopes and acceptances even when coordinated in one docking. Identify the status or certificate actually being updated.

Which Z17 is current?

The IACS page checked on 12 October 2026 identifies Rev.21 as current; apply the version incorporated in the Society’s Rules and verify the supplier certificate’s scope.

When Rev.22/23?

1 January 2027 and 1 January 2028.

Does the supplier’s report close the survey?

It supports assessment within the required scope. Verification and acceptance by the competent party, document updates and any outstanding items remain.