The U.S. Department of Labor Occupational Safety & Health Administration (OSHA)
published a final rule on improving the safety of longshoring employees who
work with vertical tandem lifts. The rule will reduce hazards related to
lifting two containers at a time using cranes by ensuring that safe work
practices are followed.

Since the 1970s, intermodalism (the containerization of cargo) has become the
dominant mode of cargo transport in the maritime industry, replacing
centuries-old, break-bulk cargo handling. In the marine cargo handling
industry, intermodalism typically involves three key components: standardized
containers with uniform corner castings; interbox connectors (such as SATLs) to
secure the containers (to each other at the four corners, to the deck of the
ship, to a railroad car, or to a truck chassis); and a type of crane called a
container gantry crane that has specialized features for the rapid loading and
unloading of containers. Because intermodalism is highly dependent on
standardized containers and connecting gear, several international
organizations have developed standards for equipment and practices to
facilitate intermodal freight operations. This helps ensure that containers and
interbox connectors are sized and operate properly so
that containers and connectors from different manufacturers will fit together.

There are several ISO standards addressing the design and operational handling
of intermodal containers and interbox connectors. In particular, ISO 3874,
Series 1 Freight Containers--Handling and Securing, addresses the size and
strength of containers and corner castings, the size and strength of the
interbox connectors, and proper lifting techniques. During shipment, containers above deck are
secured by interbox connectors to each other and to the deck of the ship. In
the conventional loading and unloading process, the container gantry crane
lifts one container (either 6.1 or 12.2 meters long) at a time, using the
crane's specially developed spreader beam. ISO 3874 also addresses the lifting
of two 12.2-meter containers end to end but, until 2003, it had not addressed
the practice of VTLs. A VTL is the practice of a container crane lifting two or
more intermodal containers, one on top of the other, connected by a particular
type ofinterbox connector known as a semi-automatic twistlock or SATL.

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AplusA-online.de - Source: U.S. Department of Labor Occupational Safety & Health Administration