Dead Weight Tonnage
Dead Weight Tonnage, abbreviated as DWT, D.W.T., d.w.t., or dwt, is a measure of how much weight a bulk carrier is carrying or can safely carry; it does not include the weight of the bulk carrier itself. Dead Weight Tonnage is the sum of the weights of cargo, fuel, fresh water, ballast water, provisions, passengers, and crew.
Dead Weight Tonnage is often used to specify a bulk carrier's maximum permissible deadweight (i.e. when it is fully loaded so that its Plimsoll line is at water level), although it may also denote the actual Dead Weight Tonnage of a bulk carrier not loaded to capacity. It should not be confused with displacement, which includes the bulk carrier's weight measured in tons of water displaced, nor other volume or capacity measures such as gross tonnage or net tonnage (or their more archaic forms gross register tonnage or net register tonnage). Dead Weight Tonnage is now usually given internationally in tonnes (metric tons). In modern international shipping conventions such as the International Convention for the Safety of Life at Sea and the International Convention for the Prevention of Pollution From Ships, deadweight is explicitly defined as the difference in tonnes between the displacement of a bulk carrier in water of a specific gravity of 1.025 (corresponding to average density of sea water) at the draft corresponding to the assigned summer freeboard and the light displacement (lightweight) of the bulk carrier.
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