What trends or values must the gas monitoring system automatically detect or calculate?

• A. Gas concentrations, CO/O2 deficiency ratio (Grahams ratio), CO/CO2 ratio, Gas explosibility
• B. Ambient temperature and humidity only
• C. Dust concentration and particle size
• D. Pressure and flow velocity

Answer: (A)

Gas monitoring is about keeping the mine atmosphere safe by continuously measuring the actual gas levels and deriving indicators that show when those levels could become dangerous. The system must automatically detect gas concentrations and compute ratios and a risk indicator that directly relate to explosion potential and oxygen balance: the CO/O2 deficiency ratio (Grahams ratio) to gauge how much combustion risk exists as oxygen drops, the CO/CO2 ratio to help identify gas sources and combustion conditions, and the overall gas explosibility to determine if the mixture sits in the flammable range. These outputs provide immediate alarms and drive ventilation responses when conditions become unsafe. While ambient temperature and humidity, dust concentration, particle size, and parameters like pressure and flow velocity are relevant to overall mine safety and ventilation management, they are not the core outputs of a gas monitoring system that must automatically detect or calculate the critical gas conditions described.