Carry out non-destructive testing such as tests for cracks on the legs of oil rigs at sea.
Check and maintain diving equipment such as helmets, masks, air tanks, harnesses and gauges.
Communicate with workers on the surface while underwater, using signal lines or telephones.
Cut and weld steel, using underwater welding equipment, jigs, and supports.
Descend into water with the aid of diver helpers, using scuba gear or diving suits.
Inspect and test docks, ships, bouyage systems, plant intakes and outflows, and underwater pipelines, cables, and sewers, using closed circuit television, still photography, and testing equipment.
Install pilings or footings for piers and bridges.
Install, inspect, clean, and repair piping and valves.
Obtain information about diving tasks and environmental conditions.
Operate underwater video, sonar, recording, and related equipment to investigate underwater structures or marine life.
Perform activities related to underwater search and rescue, salvage, recovery, and cleanup operations.
Perform offshore oil and gas exploration and extraction duties such as conducting underwater surveys and repairing and maintaining drilling rigs and platforms.
Recover objects by placing rigging around sunken objects, hooking rigging to crane lines, and operating winches, derricks, or cranes to raise objects.
Remove obstructions from strainers and marine railway or launching ways, using pneumatic and power hand tools.
Repair ships, bridge foundations, and other structures below the water line, using caulk, bolts, and hand tools.
Salvage wrecked ships and/or their cargo, using pneumatic power velocity and hydraulic tools, and explosive charges when necessary.
Set or guide placement of pilings and sandbags to provide support for structures such as docks, bridges, cofferdams, and platforms.
Take appropriate safety precautions, such as monitoring dive lengths and depths, and registering with authorities before diving expeditions begin.
Take test samples and photographs to assess the