What must be done before returning to the mine if risk is not at an acceptable level?

• A. Return after supervisor approval
• B. Must not return to mine until risk is at an acceptable level
• C. Return after training
• D. Can return after 1 hour

Answer: (B)

The important idea here is that entry to the mine is controlled by risk level. If the current risk is not within acceptable limits, you don’t go back in. Safety rules require that any hazards be brought to an acceptable level before re-entry is allowed, because continuing with unacceptable risk could cause serious harm.

In practice, that means the scene must be cleared and risk must be reduced or mitigated to meet defined safety criteria before anyone returns. This could involve additional controls, re-evaluating the hazard, or restoring conditions (like ventilation or atmosphere) until they are within acceptable limits, and then obtaining the necessary clearance or verification to resume work.

Supervisor approval or training alone does not convert an unacceptable risk into an acceptable one, and a fixed wait time (like one hour) does not guarantee that the risk has been reduced.