A specialty classification that involves installation, maintenance and repair of boilers and associated gas and steam piping for residential, commercial or industrial use. The scope of work includes power boiler installations, hot-water heating systems and steam fitting, including fire-tube and water-tube steel power boilers and hot-water heating low pressure boilers, steam fitting and piping, fittings, valves, gauges, pumps, radiators, convectors, fuel oil tanks, fuel oil lines, chimneys, flues, heat insulation and all other equipment, including solar heating equipment associated with these systems and associated welding. This classification requires general knowledge of boilers, fuels, valves and controls, pumps, piping and traps and other components and accessories. 48