Pedestrian and Dozer Conflict in a Busy Borrow Pit
A borrow pit 60 m by 40 m supplies fill to a conveyor hopper. Inside the pit a 20 t dozer pushes material 25 m to the hopper, a 22 t excavator loads dumpers, and two labourers work on the floor-one spotting trucks, one clearing spillage near the hopper. All traffic uses a single 6 m access ramp. The dozer's blade is 3.4 m wide and the operator's eye level is about 2.9 m. Noise is 92 dB(A) at the operator's ear, and dust is visible. There is no marked pedestrian route. At 10:15 a labourer walks from the hopper toward the dozer's left side to retrieve a shovel, passing within 8 m of the blade while the dozer is reversing. The dozer has a reversing alarm and a rear-view camera, but the camera lens is mud-covered.
1. What went wrong, and what immediate action should the operator take?
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The immediate action is to stop the dozer, lower the blade, select neutral, apply the parking brake and wait until the labourer is acknowledged and clear. The operator should not shout and keep reversing.
What went wrong:
- The labourer entered the machine's working area without radio contact or eye contact, within 8 m of the blade. On this site the rule should be no pedestrian within 15 m of an operating machine unless the operator has stopped and acknowledged them.
- The reversing camera was mud-covered, so a designed control was not available. The reversing alarm alone is not enough, especially with 92 dB(A) noise and dust.
- There was no marked pedestrian route, and people and plant shared a single access ramp and the pit floor.
- The labourer was retrieving a shovel-a non-essential task that should have waited or been done under a planned stop.
The operator's first duty is to stop and protect the person, then report the near miss.
2. Design a workable exclusion and communication arrangement for this pit.
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The pit needs physical separation and a positive communication rule, not just high-visibility clothing.
- Mark a pedestrian route along the pit wall or behind a barrier, with a designated crossing point. People should not cross the machine working area to reach the hopper.
- Set an exclusion radius of at least 15 m around an operating dozer, marked with cones or barriers. Entry is only allowed when the operator has stopped, acknowledged the person and agreed the task.
- Use radios or agreed hand signals; require eye contact before anyone approaches. The spotter should face the machine and stay visible.
- Manage the ramp as one-way or signal-controlled, with a banksman during peak movements. Keep dumpers from passing a pedestrian on the ramp.
- Clean the camera at the start of each shift and treat it as a defect if it is not usable; do not rely on it as the only reversing aid.
- Suppress dust so operators and pedestrians can see, and brief the arrangement at the start of every shift.
A near miss like this should trigger a review of the whole traffic management plan, not just a warning to the labourer.
3. What would you do about the mud-covered camera and the single access ramp?
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The camera is a safety device only if it works. I would report it as a defect, clean the lens, check the display in the cab and confirm the view is clear before reversing. If it cannot be restored, I would not treat the camera as available; reversing would need a spotter or a planned route with no pedestrians behind the machine. Cleaning the lens is a temporary fix, so the cause-mud thrown onto the lens-should be addressed, for example with a guard or a cleaning routine.
The single 6 m ramp mixes dumpers, the dozer, the excavator and pedestrians. I would ask for a traffic management plan: one-way operation or radio-controlled movements, a banksman at the ramp, a passing bay if two-way working is unavoidable, and pedestrians kept off the ramp while plant is moving. Until that is in place, the risk of a head-on or run-over incident remains high.