Unmodified risk rating: 5D (V. High risk)
Current controls:
- Curved chute (top face open)
Controls to be added:
- Completely enclosed chute (top face closed)
- Safety procedures to ensure personnel maintain a safe distance when the vehicle is active
- Slower bucket movement to decrease momentum of ore
Modified Risk rating: 3A (Low risk)
Particulate matter: The bucket dumps its load onto the chute with a significant enough force to raise dust, and small particles of broken up ore, into the surrounding air. This brings the risk of inhalation of harmful particles to workers in the vicinity, as well as obscuring the driver’s vision, leading to likely accidents. These particulates may also be potentially explosive depending on their makeup.
Unmodified risk rating: 4E (High risk)
Current controls: none
Controls to be added:
- Spray a continuous mist of water to concentrate particulates & bring them out of the air
- Use a vacuum system to trap the particulates
Modified Risk rating: 1B (Low risk)
Reduced driver vision: The design of the prototype is such that the driver’s frontal vision is impaired by the bucket, particularly as it moves above the driver’s compartment to the chute. Again, this could lead to accidents within the mine tunnels due to reduced line of sight from the driver’s compartment.
Unmodified risk rating: 4B (Medium risk)
Current controls: none
Controls to be added:
- Suitably mounted mirrors on the vehicle
- CCTV cameras with monitors in the driver’s cab
Modified Risk rating: 3A (Low risk)
Diesel fumes: The full-scale model of the prototype runs on a diesel engine, which emits significant atmospheric contaminants. In the enclosed environment of a mine, these exhaust fumes can cause both long-term and short-term health issues for workers who are overexposed, with deadly consequences in high enough concentrations. However, current mines employ ventilation systems that are designed to remove these contaminants.
Unmodified risk rating: 3A (Low risk)
Current controls:
- Fan-powered ventilation ducts
- Legislation dictating minimum ventilation levels for safety
- Overall monitoring of air composition
Controls to be added:
- ‘Scrubber’ system within engine
- Localised monitoring of air composition
Modified Risk rating: 2A (Low risk)
Conclusion: The unmodified design prototype presents several hazards, of which either the consequence or likelihood are unacceptably high. By implementing various controls, we can greatly reduce the risk of ore escaping the chute, particulate matter in the air and impaired driver vision due to the bucket.