A professional who controls temperature, chemical composition, and level of cryolite baths in reduction pots to smelt aluminum oxide into aluminum. Respnsibilities include:

• Breaks off sample piece of crust formed on bath surface, and grinds it into powder, using roll crusher.
• Routes sample to laboratory for analysis.
• Dips out sample of solution and pours it into containers, using ladle.
• Drops chemicals into sample and notes resultant color.
• Adds specified amounts of chemicals and alloys to bath, according to color shade of sample, to maintain solution at specified level and composition.
• Measures current flow and voltage between electrical connections on pots, using meters, and computes voltage drop between connections.
• Measures temperature of bath, heat exchangers, and heat-control pipes, using pyrometer, and turns rheostat to regulate temperature.
• Verifies specified distance between electrodes, using measuring rod.
• Measures depth of bath, and computes amount of aluminum available for tapping.
• Records tests made, amount of chemicals and alloys added to bath, and amount of aluminum tapped from pots.