A professional who tends machine that segregates particles of dry materials, such as sand, powdered minerals, feed, resins, and chemicals, into batches of uniform size by sifting through one or more oscillating screens. Respnsibilities include:

• Bolts or clamps screen of specified mesh to frame, using handtools.
• Pours or shovels specified quantities of material into hoppers or onto feed conveyor of machine, manually or using hoist or lift truck.
• Positions takeoff conveyor, bins, or drums under screens to receive sifted material.
• Throws switch to activate takeoff conveyor or removes full containers manually or using hoist or truck.
• May measure or weigh and maintain records of material sifted.
• May lubricate machine and conveyors.