Skip to content
Department of Labor Seal U.S. Department of Labor
Mine Safety and Health Administration
Protecting Miners' Safety and Health Since 1978
Photos representing the mining workforce
Department of Labor Seal www.msha.gov [skip navigational links]
 Search MSHA Advanced Options | Help
Find IT! in DOL | Compliance Assistance | Other Links          



UNITED STATES DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION

Rocky Mountain District
Metal and Nonmetal Mine Safety and Health

Accident Investigation Report
Surface Nonmetal Mine
(Sand & Gravel)

Fatal Powered Haulage Accident

Cox Transport Corporation
I.D. No. G3S

at
Cox Rock Portable #3 (Plant)
St. George, Washington County, Utah
Mine I.D. No. 42-02201

January 13, 1999


By

Fred H. Tisdale
Supervisory Mine Safety and Health Inspector

Darren R. Lee
Mine Safety and Health Inspector

Ronald Medina
Mechanical Engineer

Originating Office
Mine Safety and Health Administration
P.O. Box 25367, DFC
Denver, CO 80225-0367

Robert M. Friend
District Manager

GENERAL INFORMATION

Daryl Ray Youngman, truck driver, age 60, was fatally injured at about 7:15 a.m., on January 13, 1999, when he was caught between the doors of a bottom dump trailer. Youngman had no mining experience but had been driving over-the-road trucks for 33 years, the past one year and 26 weeks for his current employer. He had not received training in accordance with 30 CFR Part 48.

MSHA was notified of the accident at 8:25 a.m., on January 19, 1999, by a telephone call from the Utah Occupational Safety and Health office. An investigation was started the same day.

The Cox Rock Portable No. 3, a crushing and screening plant, owned and operated by Cox Rock Products, Inc., was located in St. George, Washington County, Utah. The principal operating official was Reid Cox, plant manager. The mine was normally operated two, 12-hour shifts a day, six days a week. A total of 15 persons was employed.

Sand and gravel was excavated from a single bench with a front-end loader and transported to the portable plant where it was crushed and screened. The finished product was stockpiled for sale as road construction aggregate.

The victim was employed by Cox Transport Corporation, an independent contractor owned by the parent of the mining company, headquartered in Centerfield, Utah. The company hauled sand and gravel from several mining operations to various construction sites. The principal operating official was Michael Cox, president. A total of 150 persons was employed, of this number fifteen persons routinely hauled material from this pit.

The last regular inspection of this operation was completed on December 16, 1998.

The weather at the time of the accident was dry, clear and about 30 degrees Fahrenheit. The sun was coming up but it was not completely light.

PHYSICAL FACTORS INVOLVED

The accident occurred near the scale house in a level area approximately 300 feet wide by 400 feet long that was used by truck drivers to check their trailers for material residue that might have been left from previous loads.

The equipment involved in the accident was a Model 353 Peterbilt Tractor and two, model 1M9 Marquez Manufacturing bottom dump trailers. Each trailer was rated at 35 cubic yard capacity. The trailer involved in the accident was at the rear of the tractor/trailer combination.

The trailer dump doors were operated by a pair of double-acting Cunningham Model AL 1888-86 pneumatic cylinders. One cylinder was at the front of the doors and the other was located at the rear. When the cylinders were extended the doors opened like a clamshell along the length of the trailer underbelly midway between the tires. The door-to-ground clearance where the victim was found was 10 inches when the doors were closed. As the doors swung open and described an arc, the clearance between the edge of the door and the ground decreased to 8 inches then increased as the doors continued to open.

The dump opening could be accessed by going underneath the trailer near the front tires and crawling toward the rear. With the doors open, the clearance was 4 feet wide and 2.5 feet from the opening to the ground.

The air flow to the cylinders was controlled by a pneumatic gate valve located under the trailer at the rear of the doors. The gate valve, manufactured by the Automatic Valve Corporation, could be operated either manually or through an electrical switch. The gate valve as manufactured, was actuated electrically by an Automatic Valve Corporation electrical solenoid poppet valve to allow remote operation from the tractor. The solenoid used on the gate control valve installed on the trailer involved in the accident was a Rexroth Corporation Type 830. This valve did not operate as designed. During correct operation, when the solenoid is deenergized, which is the door close position, the gate control valve can be manually shifted to the door open position by moving the control handle. However, upon release of the control handle it returns to its original position and the doors immediately close. The gate control valve installed on the trailer involved in the accident did not function in this manner. When the handle was released, the gate control valve remained in the door open position giving the false impression that the handle was detented. However, the detent effect was temporary and the gate control valve would shift to the door close position after varying amounts of time elapsed at which point the doors would promptly close without anyone touching the valve or the toggle switch in the cab of the truck.

The valve was disassembled at the mine site and found to contain grit inside the valve on the spool and O-rings.

The bottom two rungs were missing from the ladder at the rear of the trailer making it difficult to climb into the trailer.

DESCRIPTION OF ACCIDENT

On the day of the accident, Daryl Youngman, Sr. (victim) reported for work at the Central Yard at 6:30 a.m., his regular starting time. He had received instructions the previous day to haul material from the Cox Rock Portable No. 3 operation. Youngman drove his truck to the pit and parked in the area near the scale house.

At about 7:10 a.m., Steven Jackson, transport coordinator, saw Youngman on top of the front trailer with a flashlight checking for asphalt residue. Jackson continued weighing trucks until Kirk Harding, safety compliance director, asked him to get the license number from the rear trailer of Youngman's truck as it had been involved in a minor accident.

Jackson went to the rear trailer and wrote down the trailer and license plate numbers. He then saw Youngman lying face down on the ground underneath the dump door of the trailer. Jackson yelled for assistance and two coworkers responded. They checked for a pulse, but none was detected.

The dump doors were opened to free Youngman and he was moved from under the trailer. CPR was administered and emergency medical technicians arrived a short time later and transported the victim to a local hospital. Youngman succumbed to his injuries three days later on January 16, 1999. The immediate cause of death was listed as compressional injuries with complications.

CONCLUSION

The accident was caused by failure to block the doors to prevent movement and failure to correct the defective control valve. Contributing factors were unsafe access to the trailer due to missing rungs on the ladder, and the mine operator's failure to implement pre-operational inspection requirements to identify and correct defects on their trucks.

VIOLATIONS

Cox Transport Corporation

Order No. 7907896 was issued on January 20, 1999, under provisions of Section 103(k) of the Mine Act:

A fatal accident occurred at this mine on January 13, 1999, when a truck driver was caught in the doors of a bottom-dump trailer. This order is issued to ensure the safety of persons at this operation and prohibits the use of this tractor and trailer until MSHA determines that the trailer equipment (gate controls and gates) operate safely. The operator shall obtain approval from the authorized representative for MSHA for all actions to recover and/or restore operations of the trailer in question.

This order was terminated on January 25, 1999. Conditions that contributed to the accident have been corrected and normal mining operations can resume.

Citation No. 7911783 was issued February 8, 1999, under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 56.11001:

A fatal accident occurred at this mine on January 13, 1999, when a contractor truck driver was caught between the bottom-dump doors of the rear trailer while cleaning material from the inside. A safe means of access was not provided to the inside of the trailer in that the first two rungs of the ladder were missing. The victim gained entry through the dump opening and was fatally injured when the doors closed. The rear of this trailer had recently been repaired from a previous accident, and the two missing ladder rungs were obvious. Failure to replace the two ladder rungs is a serious lack of reasonable care which constitutes more than ordinary negligence and is an unwarrantable failure to comply with a mandatory safety standard.

This citation was terminated on February 11, 1999. The missing rungs on the ladder were replaced.

Order No. 7911784 was issued February 8, 1999, under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 56.14100(a):

A fatal accident occurred at this mine on January 13, 1999, when a contractor truck driver was caught between the bottom-dump doors of the rear trailer while cleaning material from the inside. Defects affecting safety on the equipment had not been corrected. Two rungs were missing from the ladder for access to the trailer and the valve mechanism which controlled the dump doors was defective and allowed the doors to randomly close. The truck and trailers had not been inspected for defects affecting safety before being placed in operation. Failure to ensure that a pre-operation inspection was conducted is lack of reasonable care which constitutes more than ordinary negligence and is an unwarrantable failure to comply with a mandatory standard.

This order was terminated on February 11, 1999. The trucking contractor has initiated a program to require pre-operational safety examinations of mobile equipment before placing it into service.

Citation No. 7911843 was issued on February 5, 1999, under the provisions of Section 104(a) of the Mine Act for violation of 30 CFR 56.14105:

A fatal accident occurred at this mine on January 13, 1999, when a contractor employee was caught between the bottom-dump doors of the rear trailer while cleaning material from the inside. The doors were not blocked to prevent hazardous movement.

This citation was terminated on March 1, 1999. Employees received additional training and were instructed not to enter or access trailers through the bottom dump doors. The company has committed to provide elevated work platforms at each operation for drivers to use when cleaning the inside of trailers.

Citation No. 7911846 was issued on February 5, 1999, under 103(j) of the Mine Act for violation of 50.10:

A fatal accident occurred at this mine on January 13, 1999, when a contractor truck driver was caught between the bottom dump doors of the rear trailer while cleaning material from the inside. The contractor failed to notify MSHA of the accident.

This citation was terminated on February 11, 1999. The contractor has committed to future compliance with the reporting requirements of 30 CFR Part 50.

Cox Rock Products, Inc.

Citation No. 7911845 was issued on February 5, 1999, under the provisions of Section 103(j) of the Mine Act for violation of 30 CFR 50.10:

A fatal accident occurred at this mine on January 13, 1999, when a contractor truck driver was caught between the bottom dump doors of the rear trailer while cleaning material from the inside. The mine operator failed to notify MSHA of the accident.

This citation was terminated on February 11, 1999. The mine operator has committed to future compliance with the reporting requirements of 30 CFR Part 50.

Related Fatal Alert Bulletin:
Fatal Alert Bulletin Icon FAB99M02

APPENDIX

Persons participating in the investigation were:

Cox Rock Products, Inc.

Kirk Harding ................ safety compliance director
Cox Transport Corporation
Scott Larson ................ chief of operations
Kirk Harding ................ safety compliance director
Steven Jackson ................ transport coordinator
Clayton Despain ................ truck maintenance
State of Utah, Department of Health
Edward A. Leis ................ deputy chief medical examiner, M.D.
Mine Safety and Health Administration
Fred H. Tisdale ................ supervisory mine safety and health inspector
Darren R. Lee ................ mine safety and health inspector
Ronald Medina ................ mechanical engineer