If products of combustion are detected by the gas monitoring system, where must the alarm be activated?

• A. On the surface in a position that is generally under observation to warn persons of the products' presence
• B. In the underground control room only
• C. In a helmet mounted device
• D. In the boiler room

Answer: (A)

The alarm must be activated on the surface in a position generally under observation to warn persons of the products' presence. This placement ensures that everyone on the surface, and those underground who may not be near the underground control room, receives a timely warning and can take appropriate action. Limiting the alarm to the underground control room would leave surface workers in the dark about the hazard, and a helmet-mounted device would only alert the wearer rather than the broader workforce. The boiler room is not the designated location for a mine-wide gas alarm.