A plumber is a skilled craftsperson that installs and repairs pipe systems that carry water, waste drainage, natural and medical gas in buildings. They join pipes and install fixtures like bathtubs, toilets, dishwashers, and water heaters.

A steamfitter is a master craftsman who installs many varieties of piping systems. They layout, fabricate and assemble pipes from drawings, blueprints, and specifications. They thoroughly test the piping systems for proper operation.

A boilermaker is a tradesperson who manufactures, installs, and maintains boilers, tanks, and closed vats. Boilers heat the liquid, usually water, which is used to generate electric power or provide heat to buildings, factories, or ships.

Insulators install and replace the material that saves energy and helps reduce noise in buildings and around vats, vessels, boilers, steam pipes, and water pipes. Insulators also install fire-stopping materials to prevent the spread of a fire and smoke throughout a building.