container ship

container ship, a cargo vessel, colloquially known as a ‘boxboat’. It is specially designed and built to carry dry cargo prepacked in steel containers designed to be carried by trucks or freight trains. The system is called containerization and was invented in the 1930s in New Jersey by an American, Malcolm McLean. He later founded the Sea-Land Corporation, which launched and operated the first container ship, the SS Fairland, in 1956.

Container ships have revolutionized the transport of dry cargo and carry 90% of it, with over 200 million containers being used between ports annually. There are two standard sizes of container, one 20 feet (6.1 m) long (20 ft × 8.5 ft × 8.5 ft) the other exactly twice the capacity. Although the 40-foot container is now the more common, the container capacity of a ship or port is still measured in ‘twenty-foot equivalent units’ or TEU, a 40-foot container being, of course, 2TEU.

In 2002 there were over 400 container ships worldwide with a capacity of over 3,000 TEUs. The largest currently (2004) operating is the OOCL Shenzhen, which holds 8,063 TEUs, but Lloyd's Register has calculated that it is perfectly possible to build an Ultra Large Container Ship with a carrying capacity of 12,500 TEUs. As the world's container trade is increasing in the region of 8% annually, and economy of scale is essential in such a competitive industry, this will doubtlessly be achieved within the foreseeable future.

However, such huge ships do raise environmental issues. Port authorities are obliged to widen and deepen shipping channels, and the dredging of these inevitably leads to the destruction of marine habitats. Cloudy water and sediments also adversely affect marine life.