A Leaking IBC in the Hold
Mid-voyage in the North Atlantic, a crew member reports a sharp chemical smell from a lower hold. Investigation finds a 1,000-litre intermediate bulk container of UN 3265, Corrosive liquid, acidic, organic, n.o.s., Class 8, PG II, in a rigid plastic IBC. The IBC is leaking from a bottom discharge valve fitting. About 40 litres have pooled on the hold deck and are running toward a scupper. Two other IBCs of the same product are stowed nearby, and a pallet of bagged UN 3077, Environmentally hazardous substance, solid, n.o.s., Class 9, is two metres away. The hold contains steel hatch covers and electrical junction boxes at deck level.
1. Set out the immediate response priorities and explain how the EmS and MFAG guides would be used.
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Priorities: protect people, stop the source, contain the spill, protect the ship and the environment, then clean up.
- Personnel protection. Consult the MFAG entry for the substance and the EmS Schedule. For an acidic corrosive, the MFAG guidance will direct attention to skin and eye contact and inhalation of vapour or mist; responders should wear the protective equipment indicated and avoid entering a confined hold without breathing protection if vapour is present. The hold should be ventilated with care and entry controlled.
- Stop the source. If it is safe, close or plug the discharge valve, or upright and secure the IBC. Do not create sparks or use incompatible tools near the corrosive.
- Contain. The spill is heading for a scupper. Block or seal the scupper so the acid does not enter the sea or a ballast system, and use the spill kit's absorbent or neutralizing material appropriate to an acid. The EmS Schedule for the relevant class gives the fire and spill guidance; follow its spillage provisions rather than improvising.
- Protect the ship. The acid is running toward steel hatch covers and near electrical junction boxes. Acid plus steel plus electricity is a corrosion and short-circuit risk; keep the liquid away from the junction boxes and consider isolating the circuit.
- Record and report per the vessel's safety management system and the Code's incident reporting expectations.
2. Assess the stowage of the Class 9 bagged goods two metres from the leaking IBC and whether the arrangement complied with the Code.
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The proximity is a concern, though the primary failure is the leaking IBC, not the Class 9 goods. Class 8 and Class 9 are not automatically subject to a strict segregation requirement under the general table, but the stowage must still ensure that leakage from one package cannot damage or react with another.
The bagged UN 3077 is an environmentally hazardous solid. An acid spill reaching those bags could dissolve or contaminate the packaging, and runoff could carry the Class 9 material into the sea, compounding the environmental hazard. Two metres is close enough that a 40-litre pool spreading on a flat deck could reach the pallet.
Compliance points:
- The IBC should have been stowed so that a leak from the discharge fitting would be detected and contained, and so that it did not drain toward other cargo or a scupper.
- IBCs with bottom discharge fittings are vulnerable; the Code's stowage and securing provisions call for protection against impact and for arrangements that limit the consequences of leakage.
- Environmentally hazardous goods should be stowed where a release is least likely to reach the sea.
The arrangement did not adequately consider leak pathways. After the emergency, the stowage plan should be revised to separate the corrosive IBCs from the Class 9 pallet and to place drip containment or a barrier between them.
3. What follow-up actions and records are required after the spill is controlled?
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Follow-up should cover the damaged IBC, the cargo, the ship, and the paperwork.
- The leaking IBC should be treated as damaged goods: emptied or overpacked as the Code allows, marked accordingly, and its condition documented. The other two IBCs should be inspected for the same valve defect.
- The hold deck, hatch covers, and any affected steel should be washed and neutralized as appropriate, and the washings contained rather than pumped overboard. Junction boxes should be inspected for corrosion.
- The spill kit should be replenished and the incident entered in the vessel's records, with a report to the company and, as required, to the flag and port state.
- The transport document and packing certificate for the consignment should be reviewed to confirm the IBC was properly declared and that the stowage plan reflected the leak risk.
- A debrief should feed back into the vessel's procedures for stowing IBCs with bottom fittings and for scupper protection.
The key judgement is that a Class 8 leak near steel, electricity, a scupper, and environmentally hazardous cargo is a multi-pathway problem, and the response must address all four, not just mop the deck.