Simple Solutions That Work! Issue 18

opening or closing a tap hole, starting or terminating a cast, or skimming molten metal during casting of sows and foundry ingot, it is recommended that workers wear a face shield in addition to the safety glasses. Additional guidelines may be found in ANS Z87.1, Practice for Occupational and Educational Eye and Face Protection. Foot Protection — Proper protective footwear should be worn at all times. Laceless safety toe boots or smelter/foundry boots are recommended for molten substance exposure. These shoes can be removed easily and rapidly in an emergency because they have no fasteners. Laced safety toe boots worn around molten substances must be covered with spats to prevent them from capturing the molten metal. As a precaution, laces, if permitted, should be of materials that will burn through quickly. Where there is a potential for molten metal to enter the top of the shoes, or where lower extremities are exposed to molten metal splash, leggings with spats should be worn. Safety toe shoes with metatarsal guards should be worn where there is danger of falling objects striking the foot. Hand Protection — During operations that have a potential for burn injury to the hands, industrial-type, heat resistant and/ or flame-retardant gloves should be worn. Cotton hot mill gloves are recommended as a minimum. Under most circumstances, gloves that minimize the opening at the wrist where molten metal might enter should be selected. Trunk/Extremity Protection — The trunk/ arms, and legs must be protected against cuts, punctures, abrasions, extreme heat, extreme cold, and harmful chemicals. Ordinary work clothing, if clean, in good repair, and suited to the job may be considered safe in most exposures. “Ordinary” work clothing does not protect employees from hot molten aluminum. THE BURNING ISSUE Burns have been one of the leading causes of work injuries in molten aluminum operations. The most serious injuries, of course, are the disabling burns that involve a major portion of a worker’s body. Such serious burns are generally caused by the use of inadequate or improper protective clothing and equipment. Protective clothing for workers is divided into two categories. Secondary protective clothing , according to ASTM F1002 (Standard Performance Specification for Protective Clothing for Use by Workers Exposed to Specific Molten Substances and Related Thermal Hazards), is “protective clothing designed for continuous wear for work activities in designated locations in which intermittent exposure to molten substance splash, radiant heat, and flame sources is possible. Secondary protective clothing is designed so that it will not continue to burn after exposure to, and removal of, a source of ignition. Protection against metal splash and radiant heat are secondary in intent.” While secondary protective clothing replaces “ordinary” work clothing, it does not eliminate all burns. It will, however, significantly reduce the number and severity of burns. Secondary clothing for molten aluminum casting operations may be made from specially treated cotton (non-phosphorus treatment such as FR-8), specially treated wool (Zirpro), or a special non- melting, synthetic fabric (Vinex FR-9B). Some workers, with limited exposure, wear outer garments (pants and shirts) made of 100% cotton or wool. Workers should be encouraged to wear natural fiber undergarments (“long johns”) and socks since that will provide additional protection against burns. Most synthetic materials or synthetic blends offer little or no protection against molten metal and should never be used. Research and development by fabric manufacturers and aluminum producers is continuing. Primary protective clothing, as defined by ASTM F1002, is “protective clothing designed to be worn for work activities during which significant exposure to molten substance splash, radiant heat, and flame is likely to occur. Such work activities include charging, tapping, and pouring, during which work is carried out in close proximity to molten substances and hot surfaces and contact with either is likely.” Primary clothing consists of jackets, capes, aprons, chaps, leggings, spats, and sleeves designed and fabricated from materials capable of withstanding a major assault from the substance against which it is protecting. It is worn by workers actually working with the metal. Primary protective clothing is worn over secondary protective clothing, providing a layering effect and greater protection to the worker. This clothing may be made from aluminized fabrics (which also reflect radiant heat), “Zipro” treated wool, leather, or some specialized synthetic fabrics. It is recommended that workers directly exposed to, or working with molten metal in melting, transfer, Continued on next page 33 HOW TO ISSUE