Calcium Hypochlorite: Why It Has No IMSBC Schedule

Calcium hypochlorite has no schedule in the IMSBC Code. It does not appear in Appendix 1, it is absent from the Appendix 4 index, and the UN numbers assigned to it appear nowhere in the Code text. The only occurrences of hypochlorites in the Code are inside the segregation lists of the ammonium nitrate schedules, naming the material as something the fertilizer must be separated from.

It is a packaged IMDG class 5.1 oxidising substance, carried under several UN entries distinguished by hydration state and by whether the material is a mixture. Its documented marine casualty record is a container record: self-accelerating decomposition in a heated container producing a fire that a conventional response cannot reach. The full article will cover the classification, the decomposition mechanism, the temperature dependence that drives it, and the industry guidance developed by the Cargo Incident Notification System and the International Group of P and I Clubs.

It will also cover the route a shipper proposing bulk carriage would have to take, which is IMSBC section 1.3 from the beginning: a submission of characteristics to the competent authority of the port of loading, consultation with the competent authorities of the port of unloading and the flag State because Group B hazards are plainly present, preliminary conditions of carriage set by the three, a certificate to the master, and an application to IMO within one year to add the cargo to Appendix 1.