stow profile and creating a free- surface effect and cargo shift [2].
The process is typically triggered by the exposure of the cargo to cumulative stress from ship motions during a voyage. Once a cargo has begun to liquefy or dynamically separate within the ship’s hold, the process is irreversible, and the ship’s intact stability may be adversely affected. Depending on the cargo and sea conditions, the vessel may capsize.
Typical cargoes affected by liquefaction include nickel ore, iron ore fines, bauxite fines, mineral concentrates and some by-products such as ‘red mud’, although this list is by no means exhaustive and many other solid bulk cargoes are susceptible to the risk of liquefaction.
International legal regime
The carriage of solid bulk carriages by sea is regulated by the International Maritime Solid Bulk Cargoes (“IMSBC”) Code. The Code was first adopted by the International Maritime Organisation on 04 December 2008 and entered into force on 01 January 2011. It is of mandatory application under the Safety of Life at Sea (“SOLAS”) Convention and is revised every two years. SOLAS was first adopted in 1914 after the sinking of the Titanic and by the 1960s it was recognised that the IMO should draw up and sponsor an internationally acceptable code of safe practice for the shipment of bulk cargoes. This led to the publication of the Code of Safe Practice for Solid Bulk Cargoes (the “BC Code”) in 1965, which was subsequently replaced by the IMSBC Code.
The Code divides a number of solid bulk cargoes into three groups and, when it comes to liquefaction, cargoes fall into either Group A, which consists of cargo which may liquefy, or Group C, which should not. However, a cargo only falls within Group C where it comes within the description, physical properties and characteristics set out in the schedules to the Code. If not, it should be treated as a Group A cargo. Before 2020 for instance, bauxite consisting of a defined particle size was identified as a Group C cargo; bauxite falling outside of those parameters could only safely be treated as cargo which had the
The Report • September 2022 • Issue 101 | 73
potential to liquefy. In the 2020 Edition of the Code, a new schedule was added for bauxite fines (a Group A cargo) where the product contains fine particles such that the moisture in the cargo cannot drain freely.
All IG Clubs require mandatory notification of any intention to load nickel ore from ports in Indonesia and the Philippines so that club managers can provide Members with relevant information to help manage the risks of carriage.
Liquefaction risk identified during loading
Proper compliance with the Code ought to mean that no solid bulk cargo is at risk of liquefaction during a voyage. However, cargo is often presented by the shippers as safe for shipment, but a risk of liquefaction is subsequently identified during the loading process, often after the crew carry out the complementary test procedure for determining the possibility of liquefaction laid down in the Code (known as a “can test”) or due to the involvement of a cargo surveyor. Visual observations of cargo during loading, such seeing splatter on the sides of the hold, often give cause for concern.
Cargoes may have been wrongly presented as safe to load for various reasons, ranging from mistakes during the sampling and testing process to outright fraud by the shipper. Inevitably something has gone wrong on the shore side in such situations since, before presenting
a cargo for loading, shippers are under a legal obligation under the Code to correctly identify the proper Bulk Cargo Shipping Name for any solid bulk cargo intended for shipment; determine the properties of that cargo in accordance with approved and suitable sampling and testing procedures; provide the master or his representative with appropriate information in writing sufficiently in advance of loading to enable precautions necessary for safe carriage of the cargo to be put into effect; and, provide a signed declaration in a prescribed form to the effect that the cargo has been fully and accurately described and that the test results are representative of the cargo to be loaded and correct. For a Group A cargo, the cargo declaration should be accompanied by a signed laboratory certificate stating the moisture content of the cargo and the Transportable Moisture Limit (“TML”). The TML is determined as a figure 10% in excess of the product’s flow moisture point (“FMP”), FMP being the percentage amount of moisture in the product at which, under certain conditions, the cargo may begin to begin to behave like a liquid, or “flow”. If the moisture content (“MC”) of the cargo exceeds the TML then it is not safe or suitable for shipment. The “competent authorities” (port state of departure, port state of arrival and flag state) may authorise an exemption to the Code.
Where a liquefaction risk is only identified during the loading process, it will need to be determined whether loading can continue and whether it is safe for the vessel to sail. The
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128
