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DEPARTMENT OF LABOR MINE SAFETY AND HEALTH ADMINISTRATION Southeastern District Metal and Nonmetal Mine Safety and Health Accident Investigation Report Surface Nonmetal Mine Fatal Exploding Vessels Under Pressure Accident Richardson Road Quality Aggregates, Incorporated Quality Aggregates, Incorporated Sarasota, Sarasota County, Florida Mine I.D. 08-00877 March 6, 1997 By William L. Wilkie Supervisory Mine Inspector And Mitchell Adams Mine Safety and Health Inspector Originating Office Mine Safety and Health Administration 135 Gemini Circle, Suite 212 Birmingham, Alabama 35209 Martin Rosta District Manager GENERAL INFORMATION Michael A. Litzell, welder, age 27, was fatally injured at approximately 3:00 p.m. on March 6, 1997, when a sealed flotation tank exploded while the victim was attempting to weld a tie-off to the end of the tank. The victim had a total of 10 months mining experience, all at this site. The victim reportedly had received 8 hours hazard training and placed with experienced employees for the remainder of his training. No documentation was available to verify that training had been conducted. Doug Himes, safety director, Quality Aggregates, Incorporated, notified the MSHA Birmingham District Office of the accident at 3:09 p.m. on March 6, 1997. An investigation was started the same day. Richardson Road Quality Aggregates, Incorporated, a shell and sand operation, owned by Quality Aggregates, Incorporated, was located at 6121 Richardson Road, Sarasota County, Florida. The principal operating official was Hugh N. Cannon, president. The mine normally operated one, 8-hour shift a day, five days a week and employed 33 persons. Shell was mined from a single bench using a dragline and track-hoe excavator. Underlying sand was then mined using a suction dredge. The material was transported to the plant, where it was crushed, screened, and stockpiled. The final product was marketed as aggregate, base material, and concrete additive. The last regular inspection of this operation was conducted on January 27, 1997. PHYSICAL FACTORS INVOLVED The company was in the process of replacing the flotation tanks on the dredge discharge line. The tanks, fabricated off-site by Kinney-Johnson Fabricators, Incorporated, measured 12 feet in length and 46 inches in diameter. They were fabricated from 1/8 inch thick metal. The mine operator had purchased tanks in January 1997, and had welded tie-offs to the tanks without incident. The tie-offs were used to secure boats to the discharge line on the dredge during maintenance work. The tanks delivered in January 1997, arrived at the mine with the vent caps missing and without rust-inhibiting paint being applied to the inside of the tanks. The tanks delivered on the date of the accident were sealed and the interior had been painted with a rust inhibiting paint at the order of the mine operator. A copy of the material safety data sheet for the paint, provided by the fabricator during the investigation, stated: "Do not pressurize, cut, heat, weld or expose such containers to flame. They may explode and cause injury or death." There were no labels posted on the tanks warning of this hazard. The paint had a flash point of 103 degrees Fahrenheit. The air temperature, on the day of the accident, was estimated to be in the mid 80's. DESCRIPTION OF ACCIDENT On the day of the accident, Michael A. Litzell, victim, reported to work at 7:00 a.m., his regular starting time. His primary occupation was maintenance welder. He was assigned various duties in and around the plant until approximately 2:00 p.m. when two metal flotation tanks were delivered to the mine site. Litzell was to weld a v-shaped metal tie-off on both ends of each tank prior to the tanks being installed on the dredge discharge line. He had completed welding the tie-off at one end of the tank, and was in the process of welding the tie-off at the opposite end, when the welding rod burned through the tank, resulting in an explosion. The end of the tank, which was 46-inches diameter, separated from the body of the tank, striking the victim. He was thrown approximately 26 feet by the force of the explosion. The explosion was heard throughout the plant and several employees went to the scene of the accident. The plant operator dialed 911 and summoned emergency medical assistance. The Sarasota County Paramedics arrived in approximately 10 minutes after being contacted and examined the victim. The victim was pronounced dead at the scene by paramedics from the Sarasota County Medical Examiner's office. Death was attributed to multiple blunt force trauma caused by the explosion. The victim was removed from the accident scene and taken to the morgue at the Sarasota Memorial Hospital. CONCLUSION The cause of the accident was the failure to ventilate the tank and test for flammable or explosive gases prior to beginning welding operations. VIOLATION Citation No. 4076847 Issued on March 19, 1997, under the provisions of Section 104(a) of the Mine Act for violation of Standard 56.4604: /s/ William L. Wilkie Supervisory Mine Inspector /s/ Mitchell Adams Mine Safety and Health Inspector Approved by: Martin Rosta, District Manager Related Fatal Alert Bulletin:  [FAB97M15]
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