What’s the Weight? Why Weighing of Cargo Containers is Critical

Last year in a Persian Gulf port, we finished loading for a southbound transit to East Africa on a small container ship.  Our load plan showed that we would be down to our marks once finished loading.  Over the last couple of hours, a close eye was kept on the load line to ensure we didn’t overload – only a couple of months prior, loading had to be stopped early as the vessel was down to the marks.  On this day, however, the load line never got near the water.  When the calculated draft tonnage was compared to the actual draft tonnage, close to 1000 MT of cargo appeared to be missing.  So, where did it go?

Both these situations – one, containers that are lighter than declared and two, containers that are heavier than declared are hazardous to the vessel and prevent a carrier from loading a vessel for maximum profit.  Containers that are heavier than declared can prevent a ship from loading all containers planned – a situation that we have seen frequently in Persian Gulf and East African ports recently.  If the container is heavy enough, it can potentially cause damage to cranes and equipment when loading and discharging.  At sea, an overweight container can cause higher loads than anticipated on lashing gear – potentially leading to a loss of cargo in the wrong conditions.  While the overweight container is more commonly seen, the underweight container as noted above has its own hazards.  Namely, where was the weight removed in the overall load?  Was it taken from up high?  If so, the vessel will have greater stability.  Was it taken from down low?  If so, the vessel will have less initial stability – a hazardous situation when you take into account the relatively narrow margins normally used.  The underweight container also takes away from the potential cargo carriage, i.e. more containers could have been loaded.

These situations have not gone unnoticed in the shipping industry.  Although there are requirements in SOLAS (SOLAS Regulation VI/2) for a declaration of the gross weight of the container, there is no requirement for the actual weighing of the container.  The sole exception to this actual weighing requirement is for export from the United States.  Recently, a broad spectrum of industry organizations and countries, Denmark, The Netherlands, the United States, BIMCO, the International Association of Ports and Harbors (IAPH), the International Chamber of Shipping (ICS), the International Transport Workers’ Federation (ITF), and the World Shipping Council (WSC) submitted a formal proposal to the International Maritime Organization (IMO) to require all containers to be weighed in order to determine their actual weight.

IMO MSC 89-22-17 Comments on Mis-Declared Cargo Weights (Comments and clarifications on the proposal submitted)

In July 2011, guidance was given to the IMO Sub-Committee on Dangerous Goods, Solid Cargoes and Containers as follows :

IMO DSC 16/14 Development of measures to prevent loss of containers

The target date for modifications (if any) to SOLAS is 2013.  The Sub-Committee on Dangerous Goods, Solid Cargoes and Containers is meeting between Sept. 17th and 21st and it will be of great interest what progress has been made on this issue.

One company in the industry that has moved forward with an eye on a regulation requiring the weighing of all containers  is Strainstall.  They have developed their own container weighing system that could be integrated into a normal container crane.  While the intent is to install these sensors on the spreader twistlocks on the crane, it might be better to install such sensors on straddle carriers or container stackers.  This would allow using the actual weight for planning proactively, rather than responding re-actively after the ship is loaded.

It appears that much needed regulation requiring the actual weighing of all containers is coming down the road.  Additional information on the securing of cargo containers is available in A Master’s Guide to Container Securing provided by the Standard P&I Club and Lloyd’s Register.  It contains information of which all deck officers on container ships should be aware.

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