WV Foreman Test – Ventilation UPDATED
Exam Questions and CORRECT Answers
Where shall all main fans be installed? - CORRECT ANSWER- On the Surface
The main fan must be enclosed in what kind of housing? - CORRECT ANSWER- Fireproof
The fan or fans shall be kept in what kind of operation? - CORRECT ANSWER- Continuous
Operation
When shall all employees be removed from the mine when the fan stops? - CORRECT
ANSWER- If the ventilation is not restored within 15 minutes
What shall be done before persons return to the mine after ventilation is restored? -
CORRECT ANSWER- The mine shall be examined by a certified person
When the fan stops and ventilation is restored within 15 minutes, what must be done? -
CORRECT ANSWER- The face regions and other places in the affected area shall be re-
examined by a certified person
How many openings are necessary to provide adequate ventilation? - CORRECT ANSWER-
At least 2
What is the maximum distance that mines may be developed underground before
mechanically operated fans are required? - CORRECT ANSWER- 200'
How shall mine ventilation be obtained? - CORRECT ANSWER- By the use of fans,
mechanically operated
What action shall be taken in the event of an accident to the ventilation fan? - CORRECT
ANSWER- The miners shall be ordered to withdraw from the face regions and other affected
areas immediately and the power disconnected
,What are the two systems of ventilation? - CORRECT ANSWER- Blowing and Exhaust
What is the ventilating pressure? - CORRECT ANSWER- Pressure which must be exerted
upon an air current to overcome the mine resistance
How is the ventilating pressure measured? - CORRECT ANSWER- With pressure-recording
gages or water gages
How is the ventilating pressure produced by fans? - CORRECT ANSWER- By the speed at
which the fan is operating, varying with characteristics of the fan
What affect do obstructions in airways have on the quantity of air circulated, fan speed
remaining constant? - CORRECT ANSWER- The quantity is decreased
What affect do short circuits have upon the quantity of air circulated, fan speed remaining
constant? - CORRECT ANSWER- The quantity is increased
What affect does a decrease in mine resistance have upon the performance of a fan? -
CORRECT ANSWER- The fan is enabled to circulate an increased quantity of air with no
increase in the ventilating pressure
What is the benefit of decreased mine resistance when it is not necessary to increase the
quantity of air in circulation? - CORRECT ANSWER- A saving in power can be affected by
reduced fan speed
What is meant by natural ventilation? - CORRECT ANSWER- Movements of air produced
by differences in the weights of air columns or by differences in temperature
How is natural ventilation produced? - CORRECT 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
Why is natural ventilation not reliable? - CORRECT ANSWER- The direction may reverse
with weather conditions, and when the outside temperature approximates the inside
temperature, movement may cease
, What is the most reliable means of producing ventilation in a mine? - CORRECT ANSWER-
A mechanically operated fan
With what instruments should all main fans be provided? - CORRECT ANSWER- Pressure
recording gages or water gages
What common types of fan are used? - CORRECT ANSWER- Centrifugal and axial flow
fans
How must a mine fan installation be protected from an explosion? - CORRECT ANSWER-
By explosion doors, or a weak wall
What is the purpose of explosion doors? - CORRECT ANSWER- To relieve the pressure of
an explosion before it reaches the fan
How must fan buildings be constructed? - CORRECT ANSWER- With incombustible
materials, equipped with fire proof air ducts and provided with explosion doors or a weak
wall
Where shall fans be located with respect to mine openings? - CORRECT ANSWER- They
should be offset not less than 15 feet from the nearest side of the mine opening and connected
to the opening by means of air ducts
Why should fans not be located in a mine opening? - CORRECT ANSWER- Because of the
possibility of their destruction in the event of a mine explosion
Under what circumstances may the fan be placed in front of or over a mine opening? -
CORRECT ANSWER- When the opening is not in a direct line with possible forces coming
out of the mine, and there is another opening having explosion doors or a weak wall in direct
line of forces coming out of the mine
What electrical requirement is necessary for mine fans? - CORRECT ANSWER- They must
be operated from an independent power circuit
Exam Questions and CORRECT Answers
Where shall all main fans be installed? - CORRECT ANSWER- On the Surface
The main fan must be enclosed in what kind of housing? - CORRECT ANSWER- Fireproof
The fan or fans shall be kept in what kind of operation? - CORRECT ANSWER- Continuous
Operation
When shall all employees be removed from the mine when the fan stops? - CORRECT
ANSWER- If the ventilation is not restored within 15 minutes
What shall be done before persons return to the mine after ventilation is restored? -
CORRECT ANSWER- The mine shall be examined by a certified person
When the fan stops and ventilation is restored within 15 minutes, what must be done? -
CORRECT ANSWER- The face regions and other places in the affected area shall be re-
examined by a certified person
How many openings are necessary to provide adequate ventilation? - CORRECT ANSWER-
At least 2
What is the maximum distance that mines may be developed underground before
mechanically operated fans are required? - CORRECT ANSWER- 200'
How shall mine ventilation be obtained? - CORRECT ANSWER- By the use of fans,
mechanically operated
What action shall be taken in the event of an accident to the ventilation fan? - CORRECT
ANSWER- The miners shall be ordered to withdraw from the face regions and other affected
areas immediately and the power disconnected
,What are the two systems of ventilation? - CORRECT ANSWER- Blowing and Exhaust
What is the ventilating pressure? - CORRECT ANSWER- Pressure which must be exerted
upon an air current to overcome the mine resistance
How is the ventilating pressure measured? - CORRECT ANSWER- With pressure-recording
gages or water gages
How is the ventilating pressure produced by fans? - CORRECT ANSWER- By the speed at
which the fan is operating, varying with characteristics of the fan
What affect do obstructions in airways have on the quantity of air circulated, fan speed
remaining constant? - CORRECT ANSWER- The quantity is decreased
What affect do short circuits have upon the quantity of air circulated, fan speed remaining
constant? - CORRECT ANSWER- The quantity is increased
What affect does a decrease in mine resistance have upon the performance of a fan? -
CORRECT ANSWER- The fan is enabled to circulate an increased quantity of air with no
increase in the ventilating pressure
What is the benefit of decreased mine resistance when it is not necessary to increase the
quantity of air in circulation? - CORRECT ANSWER- A saving in power can be affected by
reduced fan speed
What is meant by natural ventilation? - CORRECT ANSWER- Movements of air produced
by differences in the weights of air columns or by differences in temperature
How is natural ventilation produced? - CORRECT 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
Why is natural ventilation not reliable? - CORRECT ANSWER- The direction may reverse
with weather conditions, and when the outside temperature approximates the inside
temperature, movement may cease
, What is the most reliable means of producing ventilation in a mine? - CORRECT ANSWER-
A mechanically operated fan
With what instruments should all main fans be provided? - CORRECT ANSWER- Pressure
recording gages or water gages
What common types of fan are used? - CORRECT ANSWER- Centrifugal and axial flow
fans
How must a mine fan installation be protected from an explosion? - CORRECT ANSWER-
By explosion doors, or a weak wall
What is the purpose of explosion doors? - CORRECT ANSWER- To relieve the pressure of
an explosion before it reaches the fan
How must fan buildings be constructed? - CORRECT ANSWER- With incombustible
materials, equipped with fire proof air ducts and provided with explosion doors or a weak
wall
Where shall fans be located with respect to mine openings? - CORRECT ANSWER- They
should be offset not less than 15 feet from the nearest side of the mine opening and connected
to the opening by means of air ducts
Why should fans not be located in a mine opening? - CORRECT ANSWER- Because of the
possibility of their destruction in the event of a mine explosion
Under what circumstances may the fan be placed in front of or over a mine opening? -
CORRECT ANSWER- When the opening is not in a direct line with possible forces coming
out of the mine, and there is another opening having explosion doors or a weak wall in direct
line of forces coming out of the mine
What electrical requirement is necessary for mine fans? - CORRECT ANSWER- They must
be operated from an independent power circuit
