WV FOREMAN TEST - VENTILATION UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

WV FOREMAN TEST - VENTILATION UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS

Question:
1. Where shall all main fans be installed?
Answer:
On the Surface

Question:
2. The main fan must be enclosed in what kind of housing?
Answer:
Fireproof

Question:
3. The fan or fans shall be kept in what kind of operation?
Answer:
Continuous Operation

Question:
4. When shall all employees be removed from the mine when the fan stops?
Answer:
If the ventilation is not restored within 15 minutes

Question:
5. What shall be done before persons return to the mine after ventilation is restored?
Answer:
The mine shall be examined by a certified person

Question:
6. When the fan stops and ventilation is restored within 15 minutes, what must be done?
Answer:
The face regions and other places in the affected area shall be re-examined by a certified person

Question:
7. How many openings are necessary to provide adequate ventilation?
Answer:
At least 2

Question:
8. What is the maximum distance that mines may be developed underground before mechanically operated
fans are required?
Answer:
200'

,Question:
9. How shall mine ventilation be obtained?
Answer:
By the use of fans, mechanically operated

Question:
10. What action shall be taken in the event of an accident to the ventilation fan?
Answer:
The miners shall be ordered to withdraw from the face regions and other affected areas immediately and
the power disconnected

Question:
11. What are the two systems of ventilation?
Answer:
Blowing and Exhaust

Question:
12. What is the ventilating pressure?
Answer:
Pressure which must be exerted upon an air current to overcome the mine resistance

Question:
13. How is the ventilating pressure measured?
Answer:
With pressure-recording gages or water gages

Question:
14. How is the ventilating pressure produced by fans?
Answer:
By the speed at which the fan is operating, varying with characteristics of the fan

Question:
15. What affect do obstructions in airways have on the quantity of air circulated, fan speed remaining
constant?
Answer:
The quantity is decreased

Question:
16. What affect do short circuits have upon the quantity of air circulated, fan speed remaining constant?
Answer:
The quantity is increased

Question:
17. What affect does a decrease in mine resistance have upon the performance of a fan?
Answer:
The fan is enabled to circulate an increased quantity of air with no increase in the ventilating pressure

, Question:
18. What is the benefit of decreased mine resistance when it is not necessary to increase the quantity of air
in circulation?
Answer:
A saving in power can be affected by reduced fan speed

Question:
19. What is meant by natural ventilation?
Answer:
Movements of air produced by differences in the weights of air columns or by differences in temperature

Question:
20. How is natural ventilation produced?
Answer:
By the difference in weight of air due to the difference in temperature between outside air and mine air or
by difference in pressures

Question:
21. Why is natural ventilation not reliable?
Answer:
The direction may reverse with weather conditions, and when the outside temperature approximates the
inside temperature, movement may cease

Question:
22. What is the most reliable means of producing ventilation in a mine?
Answer:
A mechanically operated fan

Question:
23. With what instruments should all main fans be provided?
Answer:
Pressure recording gages or water gages

Question:
24. What common types of fan are used?
Answer:
Centrifugal and axial flow fans

Question:
25. How must a mine fan installation be protected from an explosion?
Answer:
By explosion doors, or a weak wall

Question:
26. What is the purpose of explosion doors?