MASTER PLUMBER PAST BOARD EXAM QUESTIONS
SET 1 EXAM 2025-2026 Questions And Correct
Answers (Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf.
A seamless drawn-brass fixture tailpiece shall be ____.
A. 24 B&S gauge
B. 20 B&S gauge
C. 22 B&S gauge
D. 26 B&S gauge ☑️ANSWER☑️B
Hub and spigot cast-iron piping in 10-foot lengths, installed horizontally,
shall be supported at intervals of not more than ____.
A. 10 feet
B. 12 feet
C. 5 feet
D. 15 feet ☑️ANSWER☑️A
Water heater vents terminate above a roof surface at least ____ from a
vertical wall.
,A. 12 inches
B. 6 inches
C. 8 feet
D. 3 feet ☑️ANSWER☑️A
The distance from the center of a water closet to any side wall or partition
shall not be closer than ____.
A. 15 inches
B. 12 inches
C. 24 inches
D. 30 inches ☑️ANSWER☑️A
Drinking fountains may be installed with ____.
A. steel pipe
B. indirect wastes
C. yoke venting
D. bell traps ☑️ANSWER☑️B
Joints at the roof around pipes shall be made watertight by the use of ____.
A. epoxy glue
,B. flashings
C. waterproof paint
D. tar and paper ☑️ANSWER☑️B
A device to prevent backflow into the potable water system is called a ____.
A. backflow connection
B. siphon leg
C. backflow preventer
D. back-siphonage ☑️ANSWER☑️C
Building sewers shall be tested by completely filling the sewer with water
from the ____.
A. lowest to the highest point
B. lowest to at least ground level
C. lowest to at least a 5-foot head
D. lowest to at least a 10-foot head ☑️ANSWER☑️A
A plumbing vent shall terminate not less than ____.
A. 3 feet from an air intake
B. 10 feet from an air intake
, C. 1 foot above the roof
D. 5 feet above a window ☑️ANSWER☑️B
Cleanouts may be omitted on a horizontal drain line less than 5 feet except
for ____.
A. bathtubs
B. water closets
C. sinks
D. showers ☑️ANSWER☑️C
Except for plastic piping systems, hot and cold water piping may be tested
with ____.
A. 100 psi air for at least 10 minutes
B. 35 psi air for at least 15 minutes
C. 50 psi air or the working pressure of the water in the system for at least
15 minutes
D. 40 psi air or 150 psi water for 10 minutes ☑️ANSWER☑️C
The depth of the finished dam of threshold for any shower, measured from
the top of the drain, shall not be less than ____.
A. 4 inches
SET 1 EXAM 2025-2026 Questions And Correct
Answers (Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf.
A seamless drawn-brass fixture tailpiece shall be ____.
A. 24 B&S gauge
B. 20 B&S gauge
C. 22 B&S gauge
D. 26 B&S gauge ☑️ANSWER☑️B
Hub and spigot cast-iron piping in 10-foot lengths, installed horizontally,
shall be supported at intervals of not more than ____.
A. 10 feet
B. 12 feet
C. 5 feet
D. 15 feet ☑️ANSWER☑️A
Water heater vents terminate above a roof surface at least ____ from a
vertical wall.
,A. 12 inches
B. 6 inches
C. 8 feet
D. 3 feet ☑️ANSWER☑️A
The distance from the center of a water closet to any side wall or partition
shall not be closer than ____.
A. 15 inches
B. 12 inches
C. 24 inches
D. 30 inches ☑️ANSWER☑️A
Drinking fountains may be installed with ____.
A. steel pipe
B. indirect wastes
C. yoke venting
D. bell traps ☑️ANSWER☑️B
Joints at the roof around pipes shall be made watertight by the use of ____.
A. epoxy glue
,B. flashings
C. waterproof paint
D. tar and paper ☑️ANSWER☑️B
A device to prevent backflow into the potable water system is called a ____.
A. backflow connection
B. siphon leg
C. backflow preventer
D. back-siphonage ☑️ANSWER☑️C
Building sewers shall be tested by completely filling the sewer with water
from the ____.
A. lowest to the highest point
B. lowest to at least ground level
C. lowest to at least a 5-foot head
D. lowest to at least a 10-foot head ☑️ANSWER☑️A
A plumbing vent shall terminate not less than ____.
A. 3 feet from an air intake
B. 10 feet from an air intake
, C. 1 foot above the roof
D. 5 feet above a window ☑️ANSWER☑️B
Cleanouts may be omitted on a horizontal drain line less than 5 feet except
for ____.
A. bathtubs
B. water closets
C. sinks
D. showers ☑️ANSWER☑️C
Except for plastic piping systems, hot and cold water piping may be tested
with ____.
A. 100 psi air for at least 10 minutes
B. 35 psi air for at least 15 minutes
C. 50 psi air or the working pressure of the water in the system for at least
15 minutes
D. 40 psi air or 150 psi water for 10 minutes ☑️ANSWER☑️C
The depth of the finished dam of threshold for any shower, measured from
the top of the drain, shall not be less than ____.
A. 4 inches
