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DATE: September 26, 2001

INCIDENT TYPE: Grader Accident

LOCATION: District 1


THE ACCIDENT: On Thursday, September 20, 2001, an accident occurred that involved a "runaway" grader. Traffic control consisted of a median crossover lane closure with northbound traffic channeled into the #1 southbound lane and southbound traffic in the two remaining southbound lanes. The section of highway had a considerable grade.

The operator had finished grading the blanket, put the grader into neutral, set down the blade, set the parking bake, and turned the motor off. He then dismounted from the grader, and went to help finish with the handwork with the rest of the crew. The operator saw the grader start to move downhill, and had attempted to run after it, but was too far away to reach it. The supervisor was on-scene, and saw that the grader was going to cross over into the oncoming traffic. Seeing that there was only one car visible, he was able to stop traffic. The grader crossed the road, and struck the parked arrow board, before coming to rest on a bank on the southbound shoulder. Traffic was allowed to continue, without incident.

The field mechanic found that the parking brake was out of adjustment. The parking brake is an over-center type brake with a manual lever that has an adjustment knob on the end of the lever. It was also noted that there is a slight valve leak on the grader that makes the left ram blade-lift bleed off. It had been written on the pre-op book, but was not a safety feature, and had planned to be repaired in the future.

CONCLUSIONS: The parking brake was not adjusted properly. This, coupled with the grade at which it was parked and the blade-lift ram pressure bleeding off, enabled the grader to roll.

RECOMMENDATIONS: Please remind all employees that it is the operator's responsibility to adjust the parking brake on an over-center type brake. Also, all vehicles shall be parked with their wheels turned AWAY from traffic. If these two practices had been followed, this accident could have been prevented.

In addition, please advise all employees to never attempt to stop a runaway vehicle by trying to enter the cab to bring the vehicle to a stop. The probability of injuring themselves while trying to stop the vehicle is greater than the possibility of stopping the vehicle.


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