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NATE AIR DISTRIBUTION EXAM 2025
BRAND NEW ACTUAL EXAM WITH
ANSWERS.
A 32-inch by 32-inch square duct is to be changed to a height of
28 inches so it will fit around an obstruction in a boiler room. How
wide must the duct be in order to maintain the same area? Round
the number off to the nearest whole number of inches.
A: 36 inches
B: 37 inches
C: 38 inches
D: 39 inches - correct answer -B: 37 inches
32 X 32 = H X 28
1024 = H28
1024/28 = H28/28
36.57 = H
Which of the following is not a sheet metal duct fitting?
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A: Register boot
B: End boot
C: 90 degree half union
D: Starting collar - correct answer -C: 90 degree half union
Which of the following is a true statement?
A: The greater the velocity, the more resistance there is to a
change in direction
B: If the duct area decreases, the velocity increases
C: When a fitting creates turbulence, the turbulence continues for
several feet down the duct
D: All of these are correct statements - correct answer -D: All of
these are correct statements
Which of the following is not a duct system type?
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A: Radial duct system
B: Parameter duct system
C: Extended plenum system
D: Equal friction system - correct answer -D: Equal friction
system
A 24-inch by 8-inch rectangular duct has an aspect ratio of
A: 1:1 ratio
B: 2:1 ratio
C: 3:1 ratio
D: 4:1 ratio - correct answer -C: 3:1 ratio
The most efficient method of air balancing a duct system is
NATE AIR DISTRIBUTION EXAM 2025
BRAND NEW ACTUAL EXAM WITH
ANSWERS.
A 32-inch by 32-inch square duct is to be changed to a height of
28 inches so it will fit around an obstruction in a boiler room. How
wide must the duct be in order to maintain the same area? Round
the number off to the nearest whole number of inches.
A: 36 inches
B: 37 inches
C: 38 inches
D: 39 inches - correct answer -B: 37 inches
32 X 32 = H X 28
1024 = H28
1024/28 = H28/28
36.57 = H
Which of the following is not a sheet metal duct fitting?
, Page | 2
A: Register boot
B: End boot
C: 90 degree half union
D: Starting collar - correct answer -C: 90 degree half union
Which of the following is a true statement?
A: The greater the velocity, the more resistance there is to a
change in direction
B: If the duct area decreases, the velocity increases
C: When a fitting creates turbulence, the turbulence continues for
several feet down the duct
D: All of these are correct statements - correct answer -D: All of
these are correct statements
Which of the following is not a duct system type?
, Page | 3
A: Radial duct system
B: Parameter duct system
C: Extended plenum system
D: Equal friction system - correct answer -D: Equal friction
system
A 24-inch by 8-inch rectangular duct has an aspect ratio of
A: 1:1 ratio
B: 2:1 ratio
C: 3:1 ratio
D: 4:1 ratio - correct answer -C: 3:1 ratio
The most efficient method of air balancing a duct system is
