2. True True True True True or false: 25 Points (circle the right answer) 1. The design of a mine ventilation system requires to comply with federal and provincial occupational safety and health regulations but accurately estimate the mine ventilation requirements in short and long term. True False The selection process of a final ventilation system should meet all the ventilation and environmental requirements and should be extremely flexible to accommodate the dynamic process of mining and the ventilation requirements can frequently change during the mine life. False 3. In mine ventilation design, air velocity is a factor that has to be minimized whenever practical. True False 4. In mines, the heat transfer process and the difference in elevation between levels result in a marked difference in temperatures, and thus air density, determine the strength of the natural ventilation. False 5. The airflow direction in the mine will be from the warmer temperature toward the lower average temperature. False 6. Natural ventilation pressure is a function of the temperature difference and the height of the air columns under consideration, and is affected by the volume (Q) of air flowing in the circuit True False 7. The presence of natural ventilation in a mine ventilated by a fan affects the performance of the device. True False 8. Operating characteristics and performance of axial fans are mainly the functions of the effect of design variables on the magnitude and relative proportions of kinetic and static energy developed by the fan. False 9. In centrifugal fan design, increasing the number of blades above a certain number decreases friction losses and increase area available for airflow. True False 10. Rotative energy in axial flow fans is converted into linear-flow energy and static head as the air leaves the impeller. False 11. In forcing, blowing or push system, air is removed from the face by the duct and discharged into the through circulation. True False 12. One of the disadvantages of exhaust or suction system is that contaminated air is removed without affecting workers. True False 13. One of the advantages of force-duct with exhaust overlap system is it provides cool air to the face and permits quick re-entry after blasting. True False 14. An overlap ventilation system is commonly used for shaft bottoms and sumps. True 15. Steel ducted exhausting systems taken from one end of the station provide adequate flow over switches and batteries, to reduce gas accumulation in electrical sub-stations and battery charging stations. False 16. Auxiliary mine ventilation is a carefully designed and utilized process in a controlled fashion to provide ventilation benefits without jeopardizing other ventilation variables. True False 17. Section 5.1 (1) specifies that an employer shall conduct audit of the workplace for the purpose of identifying, assessing and managing hazards, and potential hazards, that may expose a worker to injury or illness. True True False True False