Check and maintain diving equipment, such as helmets, masks, air tanks, harnesses, or gauges

Communicate with workers on the surface while underwater, using signal lines or telephones

Obtain information about diving tasks and environmental conditions

Inspect the condition of underwater steel or wood structures

Inspect and test docks, ships, buoyage systems, plant intakes or outflows, or underwater pipelines, cables, or sewers

Take test samples or photographs to assess the condition of vessels or structures

Repair ships, bridge foundations, or other structures below the water line, using caulk, bolts, and hand tools

Recover objects by placing rigging around sunken objects, hooking rigging to crane lines, and operating winches, derricks, or cranes to raise objects

Operate underwater video, sonar, recording, or related equipment to investigate underwater structures or marine life

Cut and weld steel, using underwater welding equipment, jigs, and supports

Salvage wrecked ships or their cargo, using pneumatic power velocity and hydraulic tools and explosive charges, when necessary

Drill holes in rock and rig explosives for underwater demolitions