To assemble, install and repair piping, fixtures and equipment used in the distribution and drainage of water and water-carried wastes, air, gas, steam, heating water, and chilled water, under low or high pressure. Install, inspect and repair water mains, service lines, sewer lines, air and gas lines, valves, gauges, pumps and fixtures, including sinks, dishwashers, water heaters, toilets, urinals, footbaths and disposals.