How far must main facilities for storing explosive materials be located from workplaces or shafts?

The correct answer is based on safety regulations regarding the storage of explosive materials. In mining operations, it is crucial to maintain a safe distance between explosive storage facilities and areas where workers are present, including workplaces and shafts. This distance is established to minimize the risk of accidental detonation or any potential hazards associated with explosives, thereby protecting the health and safety of personnel.

The 200 feet requirement reflects recognized best practices and safety protocols typically found in industry regulations, ensuring that in the event of an incident, the impact will be contained, significantly reducing the risk of injury or damage in the areas where work is being conducted.

When comparing this distance to the other options, the safety margin increases with greater distances, but 200 feet has been determined to be the minimum safe distance that balances safety with operational efficiency in a mining environment.