DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Metal and Nonmetal Mine Safety and Health
REPORT OF INVESTIGATION
Surface Nonmetal Mine
Crushed and Broken Sandstone
Fatal Fall of Person Accident
June 12, 2010
Contractor ID G908
Unimin Minnesota Corporation
Ottawa Pit and Plant
Le Sueur, Le Sueur County, Minnesota
Mine ID No. 21-00790
George F. Schorr
Supervisory Special Investigator
Carol L. Tasillo, P.E.
Maxwell A. Clark
Mine Safety and Health Administration
North Central District
515 W. First Street, Room 333
Duluth, MN 55802-1302
Steven M. Richetta, District Manager
Thomas S. Edwards, ironworker, age 46, died on June 12, 2010, when he fell off a ladder. He then went over a handrail of a stairway landing and fell 47 feet to the ground below. Edwards was standing on the ladder doing preparation work for a future weld on a ventilation duct. The ladder was located near the handrail.
The accident occurred because contractor management policies and procedures failed to ensure that persons could safely perform work while standing on a ladder where there was a danger of falling to a lower level. The victim was not wearing fall protection. Investigators could not determine if a shock or burn caused the victim to lose his balance.
Sueur County Ambulance arrived and transported the victim to a local hospital where he was pronounced dead at 3:20 p.m. by Dr. Joseph Anderson, deputy coroner for Le Sueur County. The cause of death was attributed to blunt force trauma. The medical examiner also noted an apparent electrical burn to the victim's left foot. However, investigators found no conclusive evidence the victim received an electrical shock.
INVESTIGATION OF THE ACCIDENT
The Mine Safety and Health Administration (MSHA) was notified of the accident on June 12, 2010, at 2:25 p.m., by a telephone call from Grey M. Lusty, plant manager, to the National Call Center. William H. Pomroy, mine safety and health specialist, was notified and an investigation began the same day. An order was issued pursuant to 103(j) and modified to 103(k) of the Mine Act to ensure the safety of the miners.
MSHA's accident investigation team traveled to the mine, conducted a physical examination of the accident scene, interviewed employees, and reviewed documents, equipment, and work procedures relevant to the accident. MSHA conducted the investigation with the assistance of Unimin and MOR-PPM management and employees and the Le Sueur County Coroner's office.
Location of Accident
The accident occurred on a stairway landing (Figure 1) on the exterior of the load out building. The ladder was positioned between an existing ventilation duct and another ventilation duct that was being installed (Figure 2). The elevation of the ducts placed the centerline of the existing duct at the same elevation as the top of the ladder. The duct being installed was located slightly higher and about 34 inches from the existing duct.
The plant stairs, landings, and walkways were provided with handrails. Handrails were approximately 42� inches high with a mid-rail approximately 24� inches above the walking surface. The rails were 1-inch diameter round bar. The posts were 2�-inch wide, 3/8-inch thick, flat bar that was twisted near the top rail so the flat bar was welded parallel to the underside of the top rail. The posts were welded to the steel channel supporting grating or to steel plate walkways. The posts were spaced less than 72 inches apart and were attached with two hex-head bolts at the stairways. The handrails also included a 4-inch toe board mounted about � inch above the walking surface.
The ladder involved in the accident was a Werner, fiberglass 8-foot stepladder rated at 250 pounds load capacity. The left rear rail of the ladder was cracked. The crack started at the bottom of the rail and propagated to just above the bottom horizontal strut. The crack did not appear to be new and did not exhibit signs of undue stress upon the rail. The ladder contained a brace between the rail and the bottom horizontal strut that reinforced the rail at the crack. A non-contributory violation was issued for the crack on the ladder.
Personal Protective Equipment
At the time of the accident, Thomas Edwards was wearing a standard fiberglass hardhat, an automatic darkening welder face shield, gloves, and steel-toe boots. The gloves were Tillman unlined leather welding gloves. The boots were Red Wing 8-inch leather with non-metallic toes and additional electrical hazard protection. Thomas Edwards was not wearing a personal fall protection system; however, a fall protection harness and lanyard were in a tool storage box in his pickup truck.
Welders At the time of the accident, Thomas Edwards was using a Miller SRH-444 stick welder, powered from the plant's electrical system at 277/480 volts alternating current (AC). The positive and negative welding leads connected to the welder had cuts and abrasions. A non-contributory citation was issued for this condition.
Joshua Edwards was using a Miller Pro 300 CC/CV Direct Current (DC) welding generator that operated off a Caterpillar 3013C diesel engine. Investigators examined both welders and tested the Miller SRH-444 stick welder output voltage. Neither welder was considered to be a factor in the accident.
At the time of the accident, the weather was overcast with a temperature about 60 degrees Fahrenheit and 88 percent relative humidity. Rain and thunderstorms were in the area between 9:00 a.m. and 10:15 a.m. However, lightning or any weather was not considered to be a factor in the accident.
Training and Experience
Thomas S. Edwards had approximately four years of experience conducting steel erection, plant maintenance, welding and other related work activities for either MOR-PPM or a predecessor contracting company. He had worked at Unimin approximately one month conducting steel erection and plant maintenance work. He had received training in accordance with 30 CFR Part 46.
ROOT CAUSE ANALYSIS
A root cause analysis was conducted and the following root cause was identified:
Root Cause: Contractor management policies and procedures were inadequate and failed to ensure that persons could safely perform work while standing on a ladder where there was a danger of falling.
Corrective Action: Contractor management trained all persons to recognize hazards where there is a danger of falling and to properly use fall protection where the potential falling hazards exist.
The accident occurred because contractor management policies and procedures failed to ensure that persons could safely perform work while standing on a ladder where there was a danger of falling to a lower level. The victim was not wearing fall protection and fell to the ground, 47 feet below. Investigators could not determine if a shock or burn caused the victim to lose his balance.
Unimin Minnesota Corporation
Order No. 6492745 was issued on June 12, 2010, under Section 103(j) of the Mine Act:
A fatal injury occurred at this mining operation on June 12, 2010, when in the 'special products bulk load out� area, a contract employee fell over a hand railing. The miner was working on a stairway landing located three levels above the ground floor. The mine operator was verbally issued a 103(j) order which required the mine operator to secure the area and take measures to prevent destruction of any evidence which would assist in investigating the cause or causes. At approximately 10:00 p.m. the order was modified to a 103(k) order. The 103(k) order was issued to assure the safety of all persons at this operation. In order to ensure safety of persons at the mine, the 103(k) order prohibits persons form working in the 'special product bulk load� until MSHA can determine it is safe to resume operations in the affected area. The operator shall obtain approval from an authorized representative for all actions to recover and/or restore operations in the affected area.
The order was terminated on June 23, 2010, after it was determined that conditions that may have contributed to the accident no longer existed.
Citation No. 6135233 was issued on August 6, 2010, under provisions of 104(a) of the Mine Act for a violation of 30 CFR Part 56.15005:
A fatal accident occurred at this operation on June 12, 2010, when a contractor employee fell approximately 47 feet. The victim was conducting maintenance work from a ladder on an exterior stairway landing. The ladder was positioned in a location that exposed him to a fall hazard. A safety belt and line was not being Worn while work was being performed.
The citation was terminated on August 27, 2010, after management implemented a new policy on the use of fall protection.
Related Fatal Alert Bulletin:
PowerPoint / PDF
Persons Participating in the Investigation
John Mathrole ............... Corporate Environmental Health & Safety ManagerEMCOR Group, Inc. (Parent Company to MOR-PPM, Inc.)
Bobby L. Ollis ............... Vice-President
Chadwick R. Edwards ............... Site Supervisor
David J. Rodwick ............... Regional Director, Safety NortheastUnimin Minnesota Corporation
Grey M Lusty ............... Plant ManagerJackson Kelly, PLLC
Reid E. Gronski ............... Plant Superintendent
Kathy A. Wetzel ............... Quality Control/Safety Superintendent
William R. Fox ............... Manager, Safety & Health
Karen L Johnston ............... Attorney for UniminLarson King, LLP
Caryn A Boisen ............... Attorney for MOR-PPM, Inc.Mine Safety and Health Administration
George F. Schorr ............... Supervisory Special Investigator
Carol L. Tasillo, P.E. Civil Engineer
Maxwell A. Clark ............... Electrical Engineer