A pipefitter lays out, assembles, installs, and maintains pipe systems, pipe supports, and related hydraulic and pneumatic equipment for steam, hot water, heating, cooling, lubricating, sprinkling, and industrial production and processing systems. A pipefitter plans pipe system layout, installation, or repair according to specifications, cuts, threads, and hammers pipe to specifications, using tools such as saws, cutting torches, and pipe threaders and benders. A pipefitter attaches pipes to bulkheads, structures and fixtures, such as radiators or tanks, using brackets, clamps, tools or welding equipment, modifies and maintains pipe systems and related machines and equipment components following specifications, using hand tools and power tools. A pipefitter selects pipe sizes and types and related materials, such as supports, hangers, and hydraulic cylinders, according to specifications. She/he measures and marks pipes for cutting and threading. A pipefitter assembles pipes, tubes, and fittings, according to specifications. Inspects, examines, and tests installed systems and pipe lines, using pressure gauge, hydrostatic testing, observation, or other methods. A pipefitter lays out full scale drawings of pipe systems, supports, and related equipment, following blueprints. Inspects work site to determine presence of obstruction and ensure that holes will not cause structure weakness. A pipefitter cuts and bores holes in structures, such as bulkheads, decks, walls, and mains, using hand and power tools, prior to pipe installation, turns valve to shut off steam, water, or other gases or liquids from pipe section, using valve key or wrenches.