Liquefaction is a phenomenon in which a soil-like material is abruptly transformed from a solid dry state to an almost fluid state. Many common bulk cargoes, such as iron ore fines, nickel ore and various mineral concentrates, are examples of materials that may liquefy. If liquefaction occurs on board a vessel, the stability will be reduced due to the free surface effect and cargo shift, possibly resulting in capsizing of the vessel.
DNV GL has written a guideline for the design and operation of vessels with bulk cargoes that may liquefy. The intention of this guideline is to raise the awareness of the risks of cargo liquefaction on ships and to describe what mitigating actions may be taken to reduce such risks.