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Mechanical Hvac practice test EXAM QUESTIONS
AND CORRECT DETAILED SOLUTIONS LATEST
UPDATED VERSION JUST RELEASED
Question: When a closet is designed for the installation of a clothes dryer, a minimum opening
of _____ square inches for makeup air shall be provided in the door or by other approved
means.
(A) 50
(C) 150
(B) 75
(D) 100. - CORRECT ANSWER✔✔D. a minimum opening of 100 square inches- 504.3.2
Question: The use of rectangular ducts for conveying particulates shall be _____.
(A) prohibited (B) subject to the approval of the building official (C) allowed on Class 1 systems
(D) allowed if the duct is 1 gauge thicker than round duct. - CORRECT ANSWER✔✔B. shall be
subject to the approval of the building offiical 506.2
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Question: Ducts for exhausting clothes dryers shall not be connected or installed with ____.
(A) draw bands
(B) solder
(C) metal screws or fasteners that will obstruct the flow
(D) snap lock joints. - CORRECT ANSWER✔✔C. shall not be connected or installed with metal
screws or fasteners that will obstruct the flow - 504.3.2
Question: When a compartment or space for a domestic clothes dryer is provided, a minimum
_____ diameter moisture exhaust duct of approved material shall be installed.
(A) 3 inch
(C) 5 inch
(B) 6 inch
(D) 4 inch. - CORRECT ANSWER✔✔D. - 504.3.2
Question: Aluminum construction may be used in Class 1 duct systems only. The thickness of
aluminum ducts shall be at least _____ than the gauges required for steel ducts.
(A) 1 Brown & Sharp gauge thinner
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(B) 1 Brown & Sharp gauge thicker
(C) 2 Brown & Sharp gauges thicker
(D) be plastic-lined. - CORRECT ANSWER✔✔C - 506.2
Question: Duct systems operating at elevated temperatures above 140°F (60°C) shall have
clearances from combustible materials of not less than _____ inch(es).
(A) 18
(C) 4
(B) 2
(D) 6. - CORRECT ANSWER✔✔A - 506.7.2
Question: Every exhaust duct conveying explosive or flammable vapors, fumes, or dusts shall
terminate outside of the building with clearance to any openable window or fresh air intake of
not less than _____ feet.
(A) 3
(C) 8
(B) 5
Mechanical Hvac practice test EXAM QUESTIONS
AND CORRECT DETAILED SOLUTIONS LATEST
UPDATED VERSION JUST RELEASED
Question: When a closet is designed for the installation of a clothes dryer, a minimum opening
of _____ square inches for makeup air shall be provided in the door or by other approved
means.
(A) 50
(C) 150
(B) 75
(D) 100. - CORRECT ANSWER✔✔D. a minimum opening of 100 square inches- 504.3.2
Question: The use of rectangular ducts for conveying particulates shall be _____.
(A) prohibited (B) subject to the approval of the building official (C) allowed on Class 1 systems
(D) allowed if the duct is 1 gauge thicker than round duct. - CORRECT ANSWER✔✔B. shall be
subject to the approval of the building offiical 506.2
, Page 2 of 28
Question: Ducts for exhausting clothes dryers shall not be connected or installed with ____.
(A) draw bands
(B) solder
(C) metal screws or fasteners that will obstruct the flow
(D) snap lock joints. - CORRECT ANSWER✔✔C. shall not be connected or installed with metal
screws or fasteners that will obstruct the flow - 504.3.2
Question: When a compartment or space for a domestic clothes dryer is provided, a minimum
_____ diameter moisture exhaust duct of approved material shall be installed.
(A) 3 inch
(C) 5 inch
(B) 6 inch
(D) 4 inch. - CORRECT ANSWER✔✔D. - 504.3.2
Question: Aluminum construction may be used in Class 1 duct systems only. The thickness of
aluminum ducts shall be at least _____ than the gauges required for steel ducts.
(A) 1 Brown & Sharp gauge thinner
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(B) 1 Brown & Sharp gauge thicker
(C) 2 Brown & Sharp gauges thicker
(D) be plastic-lined. - CORRECT ANSWER✔✔C - 506.2
Question: Duct systems operating at elevated temperatures above 140°F (60°C) shall have
clearances from combustible materials of not less than _____ inch(es).
(A) 18
(C) 4
(B) 2
(D) 6. - CORRECT ANSWER✔✔A - 506.7.2
Question: Every exhaust duct conveying explosive or flammable vapors, fumes, or dusts shall
terminate outside of the building with clearance to any openable window or fresh air intake of
not less than _____ feet.
(A) 3
(C) 8
(B) 5
