Although plumbers, pipefitters, and steamfitters perform three distinct and specialized roles, their duties are often similar. For example, they all install pipes and fittings that carry water, steam, air, or other liquids or gases. They determine the necessary materials for a job, connect pipes, and perform pressure tests to ensure that a pipe system is airtight and watertight. Their tools include drills, saws, welding torches, and wrenches.
Plumbing is any system that conveys fluids for a wide range of applications. Plumbing uses pipes, valves, plumbing fixtures, tanks, and other apparatuses to convey fluids. Heating and cooling (HVAC), waste removal, and potable water delivery are among the most common uses for plumbing, but it is not limited to these applications. The word derives from the Latin for lead, plumbum, as the first effective pipes used in the Roman era were lead pipes.