Managing Surveys under Dual/Multiple Classification
Double class and dual class describe different arrangements. Survey responsibilities must follow the participating societies’ documents.
Operational Explanation
Coordinating two Societies means making clear who performs each activity and how each Society records its result. Comparing both status records, the agreed programme and expected reports supports booking surveys and following open conditions through to documented closure. Practical arrangements may be shared, while responsibilities, acceptance of work and document updates follow the applicable arrangement.
In double class, each of the two societies acts as if it were the sole class. In dual class, a written bilateral agreement governs work sharing. IACS PR 1B addresses these arrangements; PR 1A addresses transfer of class. Withdrawal of one class is not automatically a transfer.
| File / evidence | How to use it |
|---|---|
| Activity and due date | Record the requirement and deadline from each status, distinguishing overdue and outstanding conditions. |
| Responsibility | Identify the Society performing the survey and the Society assessing its result under the agreement or its own Rules. |
| Report and credit | Retain the report reference and confirmation of acceptance from each Society concerned. |
| Closure | Check the condition outcome, updated status and any statutory documents with the authorised party. |
Regulatory Reference
IACS PR 1B; Society Rules and applicable agreement. As of 13 October 2026: PR 1B Rev.8 current; Rev.9 from 1 January 2027.
On withdrawal from double class, the remaining Society must obtain the owner’s written intention and authorization to exchange status. It requests status within two working days of receipt at its head office or designated centre. Overdue conditions do not disappear: failure to close them at the first port where surveys can be performed can result in suspension, subject to the age-related allocation of responsibilities and any accepted direct voyage to a repair port. Withdrawal from dual class follows the agreement between the Societies. IACS PR 1B Rev.8, D.1–2; E.
Scope of Application
PR 1B covers double/dual class within its scope. For more than two societies, verify specific agreements and Rules; flag statutory delegation must be checked separately.
Unless otherwise stated, PR 1B Application covers ships over 100 GT, excluding inland waterway vessels, within the Society and vessel scope specified by the procedure. Use the edition applicable to the activity date: Rev.8 applies from 1 January 2026.
Procedure / How to Complete It
- Identify double or dual class and obtain the relevant agreement.
- Compare both societies’ status, deadlines and outstanding conditions.
- Agree attendance, reports, acceptance of work and condition closure in writing.
- After the survey, check both status records and affected statutory documents are updated.
Practical Example
Do not assume one society’s report automatically closes the other’s conditions: check the agreement and obtain documented confirmation of credit and status.
What Typically Goes Wrong
Confusing double and dual class; using only one status; assuming all work is automatically accepted.
Common Mistakes Mistake Library
| Mistake | Consequence | How to avoid it |
|---|---|---|
| Close both classes using only one status record | A condition or deadline of the other Society may remain open without follow-up. | Compare both status records and obtain confirmation from each Society of credit, closure and document updates. |
| Treat double class as dual class | Work may be assigned to only one Society without the necessary acceptance by the other. | Identify the arrangement and apply both Societies’ Rules or the bilateral agreement defining work sharing. |
| Treat withdrawal of one class as cancellation of its conditions | Overdue or outstanding conditions may compromise the remaining class’s validity. | Obtain written intention and authorisation, exchange status and follow conditions under PR 1B and the relevant agreement. |
What the PSCO Checks
Operational Tips
- Use a matrix of tasks, responsible society and closure evidence.
- Record confirmations from both societies.
Preparation checklist
- Arrangement and agreement identified
- Two status records reconciled
- Responsibilities and credits confirmed
FAQ
Related Topics
Certified substantive revision: 13 October 2026 · page fingerprint 1282d96f2152