On January 2, 2010, a 57 year old mechanic with 8 years of mining experience was fatally injured at a surface shop of an underground coal mine. He was repairing a 1-ton truck (mantrip) that was raised and supported by jack stands. The victim was positioned under the truck and the truck’s rear wheels were on the floor. A coworker, who was assisting, entered the truck, depressed the clutch pedal, and started the truck. The truck was in gear when it was started. The coworker’s foot then slipped off the clutch pedal of the standard transmission, causing the truck to lurch forward, fall off the jack stands, and strike the victim.
Best Practices
- Block vehicles against motion in all potential directions of movement prior to any work.
- Keep standard transmission vehicles in neutral with the park brake engaged when work is performed on the vehicles.
- The vibration of a running motor may cause blocked or jacked equipment to move or fall off of its blocks or jacks. Position yourself out of the path of travel in the event a failure occurs.
- Observe blocking and jack stands during loading and ensure they remain solid without any tilting or sliding. The slots at the head of the jack should properly couple with the jack points underneath the vehicle.
- Metal to metal contact may slide much easier than wood or other materials against metal. This is a good reason to ensure everything remains level and evenly loaded. Also, remove any grease or lubricants from the area that will contact the blocking/jack stand.
- Jacks and blocks should be positioned on level ground and ensure they are all raised to equal heights.
- If available, use a pit to perform maintenance work on the underside of mobile equipment.
Click here for: MSHA Investigation Report (pdf), Spanish Fatalgram (doc)