Hatchcovers

The relatively large number of individual cargo spaces (the SD14, for example, has eight separate, various sized cargo compartments) is another advantage when faced with several commodities to be carried at the same time, yet kept separate from each other – e.g. to avoid ‘tainting’ by smell, etc. or to enable loading and discharging at several ports during a voyage, without extra-handling of cargoes. Where a modern general-cargo tweendecker is built with the carriage of bulk commodities and containers in mind, in addition to conventional ‘tweendeck-cargoes’, the vessel can more accurately be termed a ‘multi-purpose’ ship. An example of such a ship – a Freedom Mk II – being equipped with container fittings and with retractable tweendecks that fold against the sides of the holds to facilitate the loading and discharge of bulk commodities. In order to carry goods efficiently, general-cargo vessels need built-in facilities to handle safely a whole variety of commodities, as well as equipment to load, stow, secure and discharge those goods. Most hold spaces will be provided with fire-smothering equipment – e.g. CO2 fittings – used to contain outbreaks of fire, certain commodities being prone to spontaneous combustion (e.g. bagged fishmeal) and/or easily combustible (e.g. baled jute). Some ships will be additionally equipped with mechanical or, more likely electrical ventilation in their cargo carrying spaces; useful particularly for commodities that ‘sweat’ heavily (e.g. bagged rice). Older tweendeckers may have ‘coamings’ around tweendeck hatchways, designed as a safety feature to protect those working in the tweendeck spaces from the danger of falling into the holds below. Since the 1960’s, however, with the widespread introduction of forklift trucks used to facilitate cargo handling, these tweendeck coamings have been almost universally dispensed with, the tweendeck hatchcovers fitting level with the surrounding tweendeck floor and providing a clear, flat unobstructed area. Such vessels, unobstructed by tweendeck hatch-coamings, are termed ‘flush tweendeckers‘.