How should mine rescue teams maintain communication with each other and the fresh-air base?

Maintaining effective communication between mine rescue teams and the fresh-air base is crucial for ensuring safety and coordination during emergency situations. Using a life-line or communication system allows for reliable and consistent connectivity in the challenging environment often found in mining operations. This method typically includes physical lines or advanced systems designed specifically for underground conditions, enabling teams to relay information and receive instructions while navigating potentially hazardous areas.

The other methods, while they have their own merits, may not offer the same level of effectiveness. Handheld radios, for instance, can face interference due to underground structures and may not function properly in high-stress environments. Visible signals could be limited by visibility issues or obstructed lines of sight in a mine. Distress flares, while useful in signaling emergencies, are not suitable for ongoing communication as they provide only one-way information and can pose additional hazards in an underground setting. Thus, relying on a life-line or communication system is the most reliable approach for ensuring safety and coordination among mine rescue teams.