1. List the main sources of heat and humidity in mines.
2. Briefly describe the methods that can be used to control heat and humidity in an underground mining situation.
3. The conditions at the entrance to a crosscut are temperatures, 28°C wet bulb and 35°C dry bulb and barometric pressure 110 kPa. At the exit of the crosscut the temperatures are 31°C wet bulb and 32°C dry bulb and the barometric pressure 110 kPa. The volume flow at the entrance is 55 m3/s. Determine;
• the water picked up in litres per day ,
• the heat picked up by the air in kW ,
• the increase in relative humidity .
4. What are the primary sources of dust in underground mining operations? Detail the methods of dust control available.
5. What is methane layering and how can it be controlled in a mine ventilation system.
6. Describe the construction of an explosion proof seal.
7. What indicators can be used to determine if an underground fire is developing and how do these indicators change as the fire develops.
8. Define the following:
• Antitropal Ventilation
• Homotropal Ventilation
• Ascentional Ventilation
• Descentional Ventilation
What are the objectives of a mine ventilation system?
9. List the main ventilation contaminants.
What systems are available for the ventilation of dead end drivages? For each system, sketch the system and detail particular advantages and disadvantages of the system.
What are the advantages of siting main mine fans on surface?
10. Detail the main parameters involved in the metabolic heat balance of a human being and define the main factors, which influence a human's ability to work in a hot environment. Briefly describe the following heat stress indices, comment on any short comings and give limiting good practice values for each which can be employed for heat stress management and design purposes;
• Wet bulb temperature
• Effective temperature
• Air Cooling Power.