Safety Issues


#11WA013: Truck Driver Run Over by Propane Transport Rolling Backward at Bulk Plant

Paul* was probably frustrated.  His routine was broken by an upset condition. He had driven his propane transport five hours to make a fuel delivery to a bulk plant. When he attempted to transfer fuel from his cargo tank to the plant’s fuel unloading bulkhead, he discovered that the transfer pump was leaking. That meant no delivery that day. After making several calls he got through to his supervisor who told him to bring the rig into a shop for repairs. But that would be tomorrow morning and 50 miles away. It was getting dark, drizzling, the temperature was falling into the 30s, and he was alone. It was time to pack it up and get a motel room for the night. He got into the cab, started the engine, released the parking brake, and realized that he was not going to go anywhere…

The Propane Transport Driver

Paul was a 69-year-old bulk propane transport driver who had driven trucks most of his working life. He had hauled propane for twelve years for a previous employer. For the past three years he had been a seasonal employee for a farm supply cooperative. The cooperative sold a variety of products, including wholesale and retail propane throughout two states. He had made numerous fuel deliveries to this customer; the most recent delivery was ten days ago. He was driving a truck-tractor in combination with an MC 330 cargo tank transport semitrailer. The 10,600 gallon capacity cargo tank was laden with 8,940 gallons of liquefied petroleum gas, also known as propane.  

The Incident

Paul realized that he was not driving his transport anywhere unless he closed the metal hinged safety air brake interlock or Dixie gate.  When this gate, located on the cargo tank trailer’s undercarriage in front of the fuel loading and unloading connections, is opened an air valve is activated which engages the trailer’s brakes. While this gate is open the truck cannot be driven. The purpose of the safety airbrake interlock system is to prevent the truck driver from driving away when fuel hoses are connected to a fuel loading bulkhead or not properly stored for travel. Paul then got out of the cab, leaving the truck running and the parking brake still released. He walked around to the trailer’s right side where the Dixie gate was located and closed the gate using a metal pin to keep it in place during transport. The trailer brakes were now released, as were the truck’s brakes. The transport began to roll backward. Paul ran alongside the transport so that he could reach the gate and open it, which would then cause the trailer brakes to engage and stop the vehicle. He succeeded in opening the gate, but as he did so, he either was hit by a tank or trailer part, or he slipped on the wet dirt driveway. He fell to the ground and was run over by the right rear wheel of the semi-tractor. The momentum of the vehicle and the fact that the air brakes take 1½ to 3 seconds to engage prevented the vehicle from stopping immediately.  The following morning the owner of the bulk plant found Paul lying under the semi-tractor’s wheel. He called emergency services personnel, who quickly arrived at the scene. The county coroner arrived and declared Paul deceased.  

The Investigation

An investigation determined that several factors contributed to the Paul’s death: 1) Failure to set the vehicle’s parking brake before exiting the cab; 2) Failure to use wheel chocks; and 3) Attempting to stop a vehicle as it rolled downhill. The bulk plant’s dirt driveway had a slope of between 3 and 5 degrees, which allowed the transport to roll backward 70 feet when the vehicle’s brakes were released.



  • Set the vehicle’s parking brake before leaving the cab.
  • Use wheel chocks.
  • Never attempt to stop a rolling vehicle from outside the cab.
  • Perform a vehicle pre-departure inspection.
  • Employers should train drivers to recognize the hazard of a vehicle rollaway and use safe work practices to prevent unintended vehicle movement.


*Not the victim’s real name.

 Photo  Photo  Photo


Washington State Department of Labor & Industries

Safety and Health Assessment and Research for Prevention (SHARP)

PO Box 44330

Olympia, WA 98504-4330


Safety Issues is presented by the National Institute for Occupational Safety and Health (NIOSH) in partnership with the National Truckers Association (NTA), with major contributions from State partners funded by NIOSH through the Fatality Assessment and Control Evaluation (FACE) Program.  The goal of the FACE Program is to prevent occupational fatalities across the nation by identifying and investigating work situations at high risk for injury and then developing and disseminating prevention strategies to those who can intervene in the workplace. State partners who contribute Safety Issues postings based on recent investigative reports are California, Iowa, Kentucky, Massachusetts, Michigan, New York, Oregon, New Jersey, and Washington.

This month’s Safety Issues is based on an investigative report from the Washington FACE Program. The complete detailed Washington FACE INVESTIGATION REPORT: #11WA013 includes additional case information, recommendations and discussion. This report can be found at Additional WA FACE Investigation Reports, Fatality Narratives, Hazard Alerts, Fatal Facts, and data summaries can be accessed through the Washington State Department of Labor & Industries at

The Safety Issues and Investigation Reports which are the products of NIOSH Cooperative State partners are presented here in their original unedited form from the states. They are intended for educational purposes only. The findings and conclusions in each report are those of the individual Cooperative State partner and do not necessarily reflect the views or policy of the NIOSH.