The steam plant consisted of 42 Yarrow boilers arranged in seven boiler rooms. Furnishings commonly include microwave ovens, hot water boilers, and electric toaster ovens. Steam locomotives had steam whistles, operated from steam produced by their boilers. Riverboats supplied steam from their propulsion boilers. Manufacturers turned to steam boilers and engines. Refilling water boilers of steam locomotives was no longer necessary. The capital and operating cost of high pressure boilers, turbines and generators are substantial. ASME has different criteria for steam boilers. The turbines used steam provided by 18 water-tube boilers. Pellet burners capable of being retrofitted to oil-burning boilers are also available. Steam was supplied by 12 cylindrical Scotch boilers. In 1859, the production of pumps and steam boilers began. Steam was provided by eight oil-fired Yarrow boilers. Steam was supplied by six Yarrow boilers operating at a pressure of . Inconel is increasingly used in the boilers of waste incinerators.