In a recent incident, a young worker parked a side boom tractor so that it pointed down a moderate slope. After she got off, the tractor started to roll forward. She jumped back onto the tractor to apply the service brake, but she slipped and fell onto the track. The tractor kept moving and pulled her through the narrow gap between the track and the side boom's frame brace. She then fell off the track onto the ground. She sustained multiple fractures.

A bungee cord was being used to hold the parking brake locking lever in place. Inspection records of the tractor also indicate that the parking brake wasn't completely reliable. Mechanical problems that are ignored often mean that equipment operators resort to unsafe operating practices. This results in the operators being injured.

• Maintain mobile equipment—including parking brakes—as specified by the manufacturer or a professional engineer. Do not circumvent safety features.
• Provide written safe work procedures for parking mobile equipment. Include specific instructions for parking on slopes and for securing equipment against rolling—for example, with chocks or blocks—when parking overnight.
• Train operators in the appropriate procedures for parking mobile equipment. Provide young and new workers with additional training to ensure they perform their work safely. Keep records of all training.
• Provide equipment operators with the supervision necessary to ensure their safety.
• Remove from service any mobile equipment with a defect that affects safe operation. Repairs must be done by—or under the direct supervision of—a qualified person.
• Instruct employees not to try and gain access to a runaway vehicle.