MASTER PLUMBER BOARD EXAM SET 1 2026-2027
Comprehensive Frequently Tested Questions With Verified
Multiple Choice and Conceptual Actual 100% Correct
Detailed Answers
Guaranteed Pass!!Current Update
1. One material not approved for the installation of an external trap for a urinal is
____.
A. ABS
B. cast brass
C. drawn-brass tubing traps
D. cast iron - ANSWER C
2. The minimum common horizontal waste pipe serving a bathtub, a lavatory, and
a kitchen sink shall be at least ____.
A. 3 inches
B. 1 -1/2 inches
C. 2 - 1/2 inches
D. 2 inches - ANSWER D
3. What kind of joint is not allowed in cast iron pipe?
A. welded
B. bell and spigot
,C. threaded
D. soldered - ANSWER C
4. Wall-mounted water closet fixtures shall be securely bolted to ____.
A. the vent piping
B. the drain piping
C. a closet bend
D. metal supporting members - ANSWER D
5. The tailpiece for a lavatory shall not be less than ____.
A. 1-1/4 inch
B. 1-1/2 inch
C. 1 inch
D. 1-3/8 inch - ANSWER A
6. Unless serving sinks or urinals, cleanouts may be omitted on a horizontal drain
line that is
A. greater than 2.0 meters
B. less than 1.5 meters
C. equal to 2.0 meters
D. none of these - ANSWER B
,7. What kind of concealed connections on fixtures that it is required to provide an
access panel or utility at least 0.3 meter in its least dimension for easy inspection
and repair?
A. slip joint
B. hubless
C. ball and socket
D. flanged - ANSWER A
8. The sizing of gas vents for category II, III and IV shall be in accordance with
____.
A. the manufacturers guide
B. the manufacturers instructions
C. the gas company
D. the vent connector company - ANSWER B
9. For a vertical drainage line that is installed to be truly in vertical position, what
is the allowed degree of the branch to be used?
A. 15
B. 60
C. 45
D. 22.5 - ANSWER B
10. The developed length between the trap of a water closet and its vent shall not
exceed ____.
, A. 4 feet
B. 12 inches
C. 30 inches
D. 6 feet - ANSWER D
11. Single-wall metal pipe shall terminate at least 5 feet in vertical height above
the highest connected equipment ____.
A. within a horizontal distance of 10 feet
B. draft hood
C. draft hood outlet or flue collar
D. or approved cap on the roof - ANSWER C
12. When sizing a copper fuel-gas piping system that has an inlet pressure of less
than 2 psi with a pressure drop of 0.3 inch w.c., the maximum cubic feet per hour
of gas flow allowed through a 5/8-inch O.D. ACR tube 75 feet in developed length
is ____.
A. 13
B. 48
C. 27
D. 68 - ANSWER C
13. No trap for any clothes washer standpipe shall be installed ____.
Comprehensive Frequently Tested Questions With Verified
Multiple Choice and Conceptual Actual 100% Correct
Detailed Answers
Guaranteed Pass!!Current Update
1. One material not approved for the installation of an external trap for a urinal is
____.
A. ABS
B. cast brass
C. drawn-brass tubing traps
D. cast iron - ANSWER C
2. The minimum common horizontal waste pipe serving a bathtub, a lavatory, and
a kitchen sink shall be at least ____.
A. 3 inches
B. 1 -1/2 inches
C. 2 - 1/2 inches
D. 2 inches - ANSWER D
3. What kind of joint is not allowed in cast iron pipe?
A. welded
B. bell and spigot
,C. threaded
D. soldered - ANSWER C
4. Wall-mounted water closet fixtures shall be securely bolted to ____.
A. the vent piping
B. the drain piping
C. a closet bend
D. metal supporting members - ANSWER D
5. The tailpiece for a lavatory shall not be less than ____.
A. 1-1/4 inch
B. 1-1/2 inch
C. 1 inch
D. 1-3/8 inch - ANSWER A
6. Unless serving sinks or urinals, cleanouts may be omitted on a horizontal drain
line that is
A. greater than 2.0 meters
B. less than 1.5 meters
C. equal to 2.0 meters
D. none of these - ANSWER B
,7. What kind of concealed connections on fixtures that it is required to provide an
access panel or utility at least 0.3 meter in its least dimension for easy inspection
and repair?
A. slip joint
B. hubless
C. ball and socket
D. flanged - ANSWER A
8. The sizing of gas vents for category II, III and IV shall be in accordance with
____.
A. the manufacturers guide
B. the manufacturers instructions
C. the gas company
D. the vent connector company - ANSWER B
9. For a vertical drainage line that is installed to be truly in vertical position, what
is the allowed degree of the branch to be used?
A. 15
B. 60
C. 45
D. 22.5 - ANSWER B
10. The developed length between the trap of a water closet and its vent shall not
exceed ____.
, A. 4 feet
B. 12 inches
C. 30 inches
D. 6 feet - ANSWER D
11. Single-wall metal pipe shall terminate at least 5 feet in vertical height above
the highest connected equipment ____.
A. within a horizontal distance of 10 feet
B. draft hood
C. draft hood outlet or flue collar
D. or approved cap on the roof - ANSWER C
12. When sizing a copper fuel-gas piping system that has an inlet pressure of less
than 2 psi with a pressure drop of 0.3 inch w.c., the maximum cubic feet per hour
of gas flow allowed through a 5/8-inch O.D. ACR tube 75 feet in developed length
is ____.
A. 13
B. 48
C. 27
D. 68 - ANSWER C
13. No trap for any clothes washer standpipe shall be installed ____.
