Integrated Bilge Water Treatment System: the New Regulation 12B

IBTS: existing guidance for separating and managing bilge water; future regulation 12B approved as a draft, not yet in force.

Operational Explanation

IBTS is an integrated arrangement of drains, tanks and treatment to reduce the separator load; it is neither a universal new unit nor a discharge permit. Regulation 14 concerns equipment with its applicable scope and waivers; regulation 15 and the Polar Code govern the operation and area.

IBTS operating principle: separate oil drains routed to sludge tanks from normally oil-free water drains, avoiding indiscriminate routing of all drains to oily bilge collection. Compare actual routes, valves and tanks with approved drawings; a “clean water” label alone does not establish that discharge is permissible. Reference: MEPC.1/Circ.760, appendix 2.

Regulatory Reference

Status on 15 September 2026: MEPC 84 approved draft 12B for subsequent adoption at MEPC 85 and approved in principle the associated 2026 IBTS Guidelines and revised ORB guidance, for final approval at MEPC 85. These steps do not yet replace current references. Source: Liberian Registry, MEPC 84 summary, p. 13.

Anticipated scope — subject to adoption

12B is a draft approved for future adoption, not a currently applicable provision. Thresholds, new/existing installation transition and IOPP/ORB changes must be checked against the final adopted text before planning compliance. No statutory 12B certification is already due.

Procedure / How to Complete It

1. Identify the currently approved system: consistent drainage, collection, treatment and disposal drawings, IOPP Supplement and manuals.
2. Before retrofit or evaporation verify arrangements accepted by flag/recognised organisation, with class where relevant: safety, ventilation and routing. Verify that vents and connections match the approved configuration before commissioning.
3. Before discharge apply regulation 15: proceeding en route, concentration and mixture origin, treatment and area conditions. No ordinary Arctic/Antarctic discharge; 10 ppm in port does not permit discharge.
4. Manage collection, reception and residue through approved routes and current ORB entries; do not anticipate draft codes.
5. Retain approvals and IOPP; where available retain the voluntary IBTS Statement of Fact, without making it universally mandatory.

Practical Example

Retrofit study example: reduce contaminated drainage, verify capacities and routes, assess risks and obtain modification approvals before installation. Any evaporation follows the authorised arrangement. Demonstrating a lower separator load does not demonstrate permission to discharge.

What Typically Goes Wrong

Common Mistakes Mistake Library

Errors: treating a draft as current law; installing or modifying routes without approval; equating working equipment with permitted discharge; denying or making the voluntary Statement of Fact mandatory.

What the PSCO Checks

Operational Tips

• Identify the currently approved system: consistent drainage, collection, treatment and disposal drawings, IOPP Supplement and manuals.
• Before retrofit or evaporation verify arrangements accepted by flag/recognised organisation, with class where relevant: safety, ventilation and routing. Verify that vents and connections match the approved configuration before commissioning.
• Before discharge apply regulation 15: proceeding en route, concentration and mixture origin, treatment and area conditions. No ordinary Arctic/Antarctic discharge; 10 ppm in port does not permit discharge.
• Manage collection, reception and residue through approved routes and current ORB entries; do not anticipate draft codes.
• Retain approvals and IOPP; where available retain the voluntary IBTS Statement of Fact, without making it universally mandatory.

Preparation checklist

Educational checklist. This summary supports learning and preparation only. It does not replace the vessel’s approved procedures, manuals, statutory documents, company SMS, or applicable official requirements. Completing it demonstrates neither compliance nor readiness for an inspection: it shows that a list has been read, not that the ship is in order. Always verify the current documents carried on board.

• Identify the currently approved system: consistent drainage, collection, treatment and disposal drawings, IOPP Supplement and manuals.
• Before retrofit or evaporation verify arrangements accepted by flag/recognised organisation, with class where relevant: safety, ventilation and routing. Verify that vents and connections match the approved configuration before commissioning.
• Before discharge apply regulation 15: proceeding en route, concentration and mixture origin, treatment and area conditions. No ordinary Arctic/Antarctic discharge; 10 ppm in port does not permit discharge.
• Manage collection, reception and residue through approved routes and current ORB entries; do not anticipate draft codes.
• Retain approvals and IOPP; where available retain the voluntary IBTS Statement of Fact, without making it universally mandatory.

FAQ

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Last substantive revision of this page: 15 September 2026 · page fingerprint e34d3c102aba