(n) large watertight chamber used for construction under water

Watertight screen on enclosure used in laying foundations underwater; sometimes called a caisson.

The space between two bulkheads set close together, especially between fuel tanks (two walls separated to use for drainage or safety).

Narrow space between bulkheads or decks to prevent leakage between adjoining compartments.

A small space left open between two bulkheads as an air space, to protect another bulkhead from heat, fidre hazard or collision.

A watertight chamber or compartment attached to the outside of a ship's hull below the water line so that repairs can be made. Also called caisson.

A void or empty space separating two or more compartments for the purpose of insulation, or to prevent the liquid contents of one compartment from entering another in case of a leak.

Narrow void space between two bulkheads or floors

the space between two bulkheads set close together, especially between fuel tanks, to use for drainage or safety.

Transverse double bulkheads at least three feet apart, extending from the keel to the upperdeck, to separate one part of the ship from another. Cofferdams are located either side of the engine-room sp [..]

A void or empty space separating two or more compartments for the purpose of insulation, or to prevent the liquid contents of one compartment from entering another in case of a leak.

Double Bulkhead separating tanks from accommodation, safety measure.

In underwater archaeology, a cofferdam is a structure used to hold back water during some excavations. Large metal pieces are connected to create an enclosure around an area of the site that archaeologists are excavating. The water is then drained out, so archaeologists can work more easily.