Clearance diver

A clearance diver was originally a specialist naval diver who used explosives underwater to remove obstructions to make harbours and shipping channels safe to navigate, but later the term "clearance diver" was used to include other naval underwater work. Units of clearance divers were first formed during and after the Second World War to clear ports and harbours in the Mediterranean and Northern Europe of unexploded ordnance and shipwrecks and booby traps laid by the Germans.

In some navies, including Britain's Royal Navy (RN), work divers, which includes Ship's divers, must have a line and a linesman when possible.

The first units were Royal Navy Mine and Bomb Disposal Units. They were succeeded by the "Port Clearance Parties" (P Parties). The first operations by P Parties included clearing away the debris of unexploded ammunition left during the Normandy Invasion. Six groups of Clearance Divers including Commonwealth and European allied forces were in operation by 1945.

Naval work diver training is much longer and harder than sport diver training and has much stricter entry requirements.

For a long time navies used the heavy standard diving dress for underwater work. During and after World War II some of them started using frogman-type gearwhen frogman's kit became available. Later they started often using open-circuit scuba gear for work diving.

The Royal Australian Navy Clearance Diving Branch clearance divers also serve as combat divers.

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