What facilities must be included in at least one of seals at a mine which has been sealed?

• A. Mine entry airlock
• B. Emergency beacon
• C. Ventilation fan
• D. Lighting

Answer: (A)

The key requirement is about safe, controlled access into a sealed area. When a mine is sealed, at least one of the seals must include a mine entry airlock. An airlock provides a two-door, enclosed passage that lets people enter or leave the sealed zone without letting air or gases bypass the seal. This preserves the isolation of the sealed area, maintains the pressure differentials, and supports safe rescue, inspection, and management of the sealed section.

Other facilities aren’t the same fit for this specific requirement: an emergency beacon is important for locating a sealed area, but it doesn’t provide controlled access through the seal; a ventilation fan inside a seal would compromise the seal’s isolation; lighting is necessary for visibility but does not address entry control or seal integrity.