Underground Mine Gas Monitoring

Gas buildup in underground mines is very dangerous as it can cause explosions which can result in injury or loss of life. Such explosions are also costly as mine tunnels, mine shafts and expensive mining equipment can be destroyed. Mines have ventilation equipment to ensure there is no gas buildup but the control of these ventilation systems is difficult if there is no information on the gas levels within the mine. This application note details how monitoring in a mine may be achieved.

Application Detail

There are many manufacturers of gas monitoring equipment. One such manufacturer is Dräger which provides explosion proof and intrinsically safe gas monitors to measure noxious gases such as CO, CO2, NO, H2S, SO2 as well as O2 and N. These instruments typically provide a 4-20mA analog output or a Modbus output which can be read by Neon Remote Terminal routinely, perhaps every 1, 5 or 10 minutes to be logged, alarm limit checked and then transmitted via a communication channels to a Neon Server on a regular schedule, perhaps every 5 minutes.

Underground mines typically have one or more mine shafts, many tunnels leading from those mine shafts and one or more ventilation shafts. Neon Remote Terminal Gas Monitor Stations can be set up at many different locations within the mine to monitor gas and other local conditions, such as temperature, humidity and perhaps dust and sound.

Underground mines generally have an existing communications system within the mine. Old mines had wired systems, like a telephone. Modern mines have wireless communications systems either cell phone based or standard 802. WiFi based, with a leaky feeder / leaky coax antenna throughout the mine, and WiFi access points.

The Neon Remote Terminal / WiFi can be used in this application with data being transferred from the Neon Remote Terminals via the existing WiFi system to a Neon Server within the Mine Administration building on the surface.

The Neon Server can be used to check gas and other ambient parameters at each measuring station / at each Neon Remote Terminal and display information on a standard web browser and on a schematic diagram of the overall mine to highlight any out of limit ambient or gas parameters.
The Neon Remote Terminal can also be programmed to increase or decrease ventilation in the mine based on the current measurements. The Neon Server can be set up to check incoming data for any out of limit conditions and activate an alarm. Alarm actions can be set up to activate visual or audible alarm indicators.

Alarm actions can also be set up to email and text mine staff and mine safety officers to alert them of any out of limit / any dangerous conditions.