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DEPARTMENT OF LABOR MINE SAFETY AND HEALTH ADMINISTRATION South Central District Metal and Nonmetal Mine Safety and Health Accident Investigation Report Surface Nonmetal Mine Fatal Handling Material Accident Southern Refractories, Incorporated Contractor I.D. No. R5U at North Texas Cement Quarry and Plant I.D. No. 41-00026 North Texas Cement Company Midlothian, Ellis County, Texas February 9, 1996 By Robert White, Supervisory Mine Inspector Edward Lilly, Mine Safety and Health Inspector Originating Office Mine Safety and Health Administration 1100 Commerce Street, Room 4C50 Dallas, Texas 75242-0499 Doyle D. Fink District Manager GENERAL INFORMATION Four contractor employees were injured at about 5:45 p.m. on February 9, 1996, when a section of castable liner material they were removing from a kiln fell on them. Antonio Juarez, apprentice mason, age 25, was fatally injured. He had five years two months refractory work experience, two years ten months as an apprentice mason. Jimmy Wayne Joyce, foreman, age 52, died on February 14, 1996, of complications resulting from injuries sustained in the accident. He had 32 years 4 months refractory work experience, 21 years 4 months as a mason/foreman. Francisco Celedon, mason tender, sustained a fractured hand and Javier Flores, laborer, sustained abrasions and contusions. They both had 10 months and 9 months experience at their jobs. MSHA was notified at 6:57 p.m., on the day of the accident, by a telephone call from Don Sinkular, safety director for the cement company. An investigation was started the same day. Southern Refractories Incorporated, located in Keller, Texas, was an independent contractor enlisted by the cement company to replace the castable portion of a kiln liner in the plant. They specialized in this type of work and had performed such jobs at other operations in the area. The senior corporate official was Mark Stanfield. A total of 35 persons was employed. The contractor had started this job on February 7, 1996 and expected to complete it on or about February 10, 1996. Four persons were assigned to this site. The cement plant, owned and operated by North Texas Cement Company, was located just north of Midlothian, Ellis County, Texas. The senior operating official was Stuart Pryor, plant manager. The plant was normally operated three, 8-hour shifts a day, seven days a week. A total of 128 persons was employed. Limestone was conveyed from an adjacent quarry to the plant where sand and shale were mixed as a slurry in raw grinding mills. The slurry passed through three rotary kilns where it was roasted into clinker; gypsum was added and the mixture was ground into Portland cement. During the kiln relining job, North Texas Cement employees were welding cracks in the kiln shell and installing the brick portion of the liner. The four employees involved in the accident had not received training in accordance with 30 CFR Part 48. The last regular inspection of this operation was completed on September 21, 1995. Another inspection was conducted in conjunction with this investigation. PHYSICAL FACTORS INVOLVED The No. 3 rotary kiln, where the accident occurred, was 450 feet long and twelve feet in diameter. Southern Refractories was replacing the castable material in three different sections of the kiln and company employees were replacing a 205-foot section of brick and welding cracks in the kiln shell. The castable material was composed of fireclay aggregate castables identified as A.P. Green MC-25 and Harbison-Walker Kiln Cast 26. The section of liner that fell varied in thickness from three to five inches and covered an estimated 113 square feet. The castable liner had been installed by this contractor in 1983. The liner was suspended by approximately 450 stainless steel monolithic refractory hangers (anchors), measuring four inches long by 5/16 inches in diameter. The hangers were welded in place on nine-inch centers. Only one hanger remained welded to the kiln shell after the castable section fell. Hand-held pneumatic hammers with chisel bits were being used to break out the old liner. A portion of the nine-foot section of liner being replaced had been removed from the kiln floor two days earlier. Four contractor employees and one company employee were in the kiln at the time of the accident. Reportedly, visibility was poor due to dust generated from the chiseling being done. MSHA's technical support group performed strength tests on the liner hangers. Their consensus opinion was that fatigue loading, due to repeated bending at small angles over a long period of time, caused the liner hangers to weaken and fail. DESCRIPTION OF ACCIDENT On the day of the accident, Juarez, Joyce, Flores and Celedon reported for work at 5:30 p.m., their regular starting time. They entered the No. 3 kiln to remove the remaining portion of the nine-foot section of castable material in preparation for installing the new liner. The four men positioned themselves under the liner and began chipping with the pneumatic hammers to break out the remaining material overhead. Work progressed for about fifteen minutes when Joyce felt the liner material under his feet move, then all four of the workers were knocked down as material fell on them from above. Bryan Dickey was laying brick inside the kiln about 100 feet from the contract workers and heard the material fall. He ran up the kiln to help but could not see because of dust generated by an air hose that had been knocked loose from one of the pneumatic hammer oiler fittings. Dickey ran to the firing floor and called for assistance. Meanwhile, Celedon staggered approximately 15 feet from the fallen material and collapsed on the kiln floor. Flores was able to get on his feet and was standing nearby. Joyce's right leg was pinned and Juarez was covered by the material. Dickey and several coworkers reentered the kiln. One person went to the compressor manifold valve and turned off the air supply. Dickey and Flores uncovered Juarez's head and observed blood coming from his nose and ears. Dickey immediately went to the control room and called 911 for help while others continued to uncover Juarez. Emergency Medical Service units arrived a short time later. They freed Joyce and transported the injured workers to local hospitals. Juarez was pronounced dead on arrival and Joyce died later of complications resulting from his injuries. CONCLUSION The structural strength of the hangers suspending the liner material was severely reduced due to repeated bending under load over a long period of time, eventually causing them to fail. VIOLATIONS Citation Number 4447554
Citation Number 4447555 Issued to North Texas Cement Company 4/9/96 under the provisions of Section 104 (a), for violation of 30 CFR 56.16009: //s// Robert White Supervisory Mine Inspector //s// Edward Lilly Mine Safety & Health Inspector Approved by: Doyle D. Fink District Manager Related Fatal Alert Bulletin:  [FAB96M04]
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