7-44. What instruments are used to measure the
static pressure of an operating fan?
1. Velometer and static-pressure probe
2. Rotating vane anemometer and
3. Velometer and Pitot tube
4. Manometer and diffuser probe
7-45. Which of the following air distribution
problems in ducts can be located quickly
by measuring static pressure?
4. Each of the above
7-46. Velocity pressure readings should be taken to
determine the total air volume of a fan from
which, if any, of the following areas?
1. Fan suction
2. Fan distribution spaces
3. Downstream of the fan in an area with
4. None of the above
7-47. Velocity pressure readings should be taken
at what location inside a rectangular duct?
1. Along the perimeter at equal intervals
2. From the center of equally divided areas
of the cross section
3. Along the horizontal center line at equal
4. At any accessible location
7-48. When the average velocity pressure is
120 fpm and the cross-sectional
measurements are 18 inches by 24 inches,
what is the total airflow, in cfm, within the
7-49. The measured total air flow, in cfm, should
exceed the design cfm by approximately
10 percent for which of the following
1. To allow for slippage
2. To ensure maximum fan speed
3. To allow for leakage
4. Each of the above
7-50. At what location, in respect to the duct
configuration, should the final balancing
procedure be started?
1. Downstream of the main air return
2. In the immediate area of the fan discharge
3. At the last outlet on the farthest branch
from the fan discharge
4. In the largest spaces served by the duct
During the final balancing procedure, an air
outlet that should be discharging 90 cfm is
found to be discharging 125 cfm. Which of
the following actions should you take?
1. Leave the damper open and proceed
to the next outlet
2. Adjust the damper until the output drops
to 90 cfm
3. Decrease the fan speed
4. Restrict the flow of return air
7-52. What term is commonly used to identify fresh
air leakage into a building or room?
7-53. A minimum amount of how much fresh air is
necessary to provide sufficient oxygen and to
remove carbon dioxide for each person in a
typical office space?