Visit factories to make sure that employees and work areas are safe.
Tends vats in which fats or vegetable and animal oils are processed into glycerin and fatty acid: Pumps specified amount of fat or oil into vat and admits prescribed quantity of sulfuric acid from storage tank. Observes gauges and thermometer and turns steam valves to boil contents of vat. Pumps oil or fat to second vat and adds specified amount of distilled water and Twitchell’s reagent. Starts agitator in vat and turns steam valves to boil mixture for prescribed time. Observes mixture through sight glass in pump line and turns valves to transfer fractions of product having different color and density to respective storage tanks. Records shift production, materials used, and heating and agitating time.