Conveyor Rollers are normally manufactured from mild steel, stainless steel, PVC or aluminum. There are different types to suit for specific uses. The food processing industry uses stainless steel or PVC rollers. There are specially designed rollers that can sprayed with water to wash the material being carried. For conveyor curves, tapered rollers are used. Most roller manufacturers strive to reduce noise to the levels recommended by the Occupational Safety and Health Administration (OSHA) of the U.S. Department of Labor, by improving the design.