Final Report - Fatality #26 - June 17, 2014

OVERVIEW

On June 17, 2014, Ronald Dwayne Dunn, Customer Truck Driver, age 41, parked his bulk tanker truck at a tanker top access platform, went to the top of the platform, and opened the bulk hatch on the trailer in preparation to get loaded with cement.  Another driver noticed the victim was not on top of the truck.  The driver found that the victim was inside the tank of the truck but could not get him out and called for help.  A responder team arrived and found the victim unresponsive.  He was transported to a hospital where he was pronounced dead. 

On September 3, 2014, the Mine Safety and Health Administration (MSHA) referred the accident to the Chargeability Review Committee.  On February 2, 2015, the Chargeability Review Committee determined that this death should be charged to the mining industry.  The autopsy report indicated that the manner of death was accidental and that the cause of death was asthma exacerbated by environmental dust exposure. The toxicology screen detected levels of theophylline, the active ingredient in the asthma inhaler.  It appears Dunn may have accidentally dropped his asthma inhaler into the tank, proceeded to climb into the tank to retrieve it, and was unable to get out.

GENERAL INFORMATION

Holcim (Texas) LP, a surface cement facility located near Midlothian, Texas, is owned and operated by Holcim (Texas) LP.  The principal operating official is Michel Moser, Plant Manager.  The mine operates three 8-hour shifts per day, seven days per week.  Total employment is 81 persons. 

Limestone is mined on-site in an open pit quarry.  Rock is crushed and transported via belt conveyor to processing mills where it is heated and combined with other ingredients to create a cement powder.  The material is then transported to storage silos and loaded into railcars or over the road trucks.  The over the road trucks pull into silos where dry bulk tanker trailers, designed for fine granulated or pulverized materials, are loaded by a gravity feed system that discharges the cement into the top hatches of the trailers.  Portland cement and other cement products are sold for use at construction projects. 

Star Bulk, a hauler that transports dry bulk material including cement, frac sand, lime, and fly ash, is located in Midlothian, Texas.  The principal operating official is Frank Pender, Owner/ President. Numerous Star Bulk drivers transport cement from Holcim (Texas) LP to customers.  

MSHA completed the last regular inspection at this mine on February 6, 2014.

DESCRIPTION OF ACCIDENT

On the day of the accident, June 17, 2014, Ronald Dunn (victim) arrived at the mine at approximately 2:13 a.m. to pick up his first load of cement for the day.  Dunn left the mine at 2:35 a.m. to deliver the material to a construction site about two hours away.  At approximately 8:43 a.m., Dunn returned to the mine and reported to the shipping office.  He received a ticket and was directed to travel to Bay 3 to receive another load of cement.

Dunn drove to the load out area and positioned his tanker under an access platform just outside Bay 3.  He ascended the access platform and opened the center hatch on the bulk tanker trailer.  Dunn lowered a drop-down handrail on the tanker surrounding the hatch to safely access the tanker.

At approximately 8:50 a.m. Christopher Peterson, Truck Driver for Quality Transport, was being loaded in Bay 3. Peterson observed Dunn ascending the platform to open the hatches but turned away to watch his truck being loaded. 

Jesse Rimes, Truck Driver for Quality Transport, drove by Dunn at approximately the same time and observed Dunn kneeling at the center hatch.  Dunn made a waving motion and Rimes thought Dunn was greeting him.    

At approximately 8:58 a.m., Thomas Cruse, Truck Driver for Star Bulk, pulled behind Dunn’s truck at the access platform and made a phone call that lasted nine minutes.   During that time, he did not see Dunn. 

About 9:05 a.m.  Cruse exited his truck, walked around Dunn’s truck, climbed the access platform, looked into the center hatch, and observed a person in the tank of Dunn’s truck.  At approximately 9:11 a.m., Cruse went to the shipping office and notified Frizzell Henry, Distribution Service Technician, to report the incident.  At 9:14 a.m., the mine’s first responder team was notified and rescue efforts began immediately.  The first responder team took gas readings before making entry into the tank and found all readings to be normal.  The ambient temperature inside the tanker did not exceed 86 degrees Fahrenheit.

First responders found Dunn unresponsive and removed him from the tanker on the truck.  Dunn was transported to a local hospital where he was pronounced dead at 10:25 a. m.  The cause of death was asthma exacerbated by environmental dust exposure.

INVESTIGATION OF THE ACCIDENT

MSHA was notified of the accident by a telephone call at 9:26 a.m. on June 17, 2014, from Michel Moser, Plant Manager, to Bradley Peay, Supervisory Special Investigator, and an investigation was started the same day. 

An order was issued under Section 103(j) of the Mine Act to ensure the safety of the miners.  This order was subsequently modified to Section 103(k) of the Mine Act when the first Authorized Representative arrived at the mine.

MSHA's accident investigation team traveled to the plant, conducted a physical inspection of the accident scene, interviewed employees, and reviewed documents and work procedures relevant to the accident.  MSHA conducted the investigation with the assistance of mine and trucking company management and employees.

DISCUSSION

Location

The accident occurred at the shipping access platform, in front of Silo & Bay #3.

In order to prepare the trucks to be loaded, drivers use an elevated platform provided with handrails to open the top hatches of their bulk tanks.  The drivers then pull into silos to be loaded, and close the tank hatches after being loaded, via the access platforms. 

No witnesses observed Dunn entering the tank.  Dunn had entered the tank of the trailer through the center hatch.  He was found in the front compartment approximately 9 feet from the center hatch.

Equipment

The trailer involved in the accident is a Butler three-compartment aluminum dry-bulk tanker trailer manufactured in 1978. The trailer is pulled by a Freightliner semi- tractor. The trailer has three hatches that can receive material loaded from the top; one hatch per compartment. Discharge valves are located at the bottom of each compartment. Each hatch has a 19-inch diameter opening. The tanker is approximately 26 feet long and 9 feet deep. A spreader system is located at the rear of the tanker trailer.

Weather

On the day of the accident, the weather was clear skies, 64% humidity, 8 MPH wind, and a temperature of 76 degrees Fahrenheit.  Weather was not considered to be a factor in this accident.

Medical Analysis and Findings

A sample of the victim's blood was analyzed for alcohol and controlled substances by an independent laboratory.  Tetrahydrocannabinol was found in the blood at a concentration of 12.8 ng/ml and carboxyetrahydrocannabinol was also found in the blood at a concentration of 38.2 ng/ml.  The presence of tetrahydrocannabinol and carboxyetrahydrocannabinol indicated prior use of marijuana.

TRAINING AND EXPERIENCE

Ronald Dunn had 8 years and 42 weeks of experience driving trucks. The investigators examined the training records for the victim. He had received site-specific hazard awareness training as required.

CONCLUSION

On September 3, 2014, the Mine Safety and Health Administration (MSHA) referred the accident to the Chargeability Review Committee. On February 2, 2015, the Chargeability Review Committee determined that this death should be charged to the mining industry. The autopsy report indicated that the manner of death was accidental and that the cause of death was asthma exacerbated by environmental dust exposure. It appears Dunn may have accidentally dropped his asthma inhaler into the tank, proceeded to climb into the tank to retrieve it, and was unable to get out.

ENFORCEMENT ACTIONS

Issued to Holcim (Texas) LP

Order No. 8770025 - Issued on June 17, 2014, under the provisions of Section 103(k) of the Mine Act:

A fatal accident occurred at this operation on June 17, 2014 when a truck driver Ronald Dunn (Star Bulk) was found inside the bulk trailer non-responsive. This order is being issued to assure the safety of all persons at this operation. It prohibits all activity at the Shipping Access Platform and the Bulk Truck #1053 Freightliner LIC: RN-9-X22 not be moved until MSHA has determined that it is safe to resume normal operation in the area. The mine operator shall obtain prior approval from an authorized representative for all actions to recover and/or restore operations to the affected area.

The order was terminated on June 19, 2014, after conditions which contributed to the accident no longer existed.

APPENDIX A

PERSONS PARTICIPATING IN THE INVESTIGATION