Massachusetts Plumbing Code ACTUAL EXAM
2025/2026 EXPERT VERIFIED QUESTIONS WITH
DETAILED ANSWERS| GUARANTEED PASS
How far can a trap arm go 1 1/2" 2" 3" 4" - ANSWER✔✔-5' 6' 8' 10'
What is the maximum water pressure going into a residential dwelling -
ANSWER✔✔-80 psi
What is the smallest drain piping allowed underground - ANSWER✔✔-2"
What's the minimal size vent going through a roof - ANSWER✔✔-2"
How many pounds in a gallon of water - ANSWER✔✔-8.33 lbs
How many gallons in a cubic foot of water - ANSWER✔✔-7.5
How much does a square foot of water weigh - ANSWER✔✔-62.5 lbs
What is the minimal size piping for drainage going through a foundation wall -
ANSWER✔✔-4"
,What is the minimal size water main underground - ANSWER✔✔-3/4"
How far should a dwv vent go through the roof - ANSWER✔✔-18-24"
What is the max temp for a shower head - ANSWER✔✔-112 degrees
What is the maximum distance for a common vent at different levels -
ANSWER✔✔-10"
What is the minimal liquid trap seal - ANSWER✔✔-2"
What must be stamped on the lip of every S.U. Gasket - ANSWER✔✔-ASTM, SV
or XH neoprene, manufactures name
How do you calculate the size of an air gap - ANSWER✔✔-It must be at least
twice the size of the diameter of the drain it serves
(into a receptor, sink, floor drain, or inlet side of a trap)
What is the minimal pounds of grease per gallon of flow - ANSWER✔✔-2 pounds
Minimal size water heater that requires a safe pan - ANSWER✔✔-6 gallons
what is the multiplier for a 45 degree offset - ANSWER✔✔-Rise x 1.414 = offset
Area of a triangle formula - ANSWER✔✔-A=1/2bh (bxh divide by 2)
, What temperature does water boil at - ANSWER✔✔-212 degrees Fahrenheit
What temperature does water freeze at - ANSWER✔✔-32 degrees Fahrenheit
Volume of a rectangle - ANSWER✔✔-L x W x H
Volume of a triangular solid - ANSWER✔✔-Bxh divided by 2 x L
How many gallons in a fixture unit - ANSWER✔✔-7.5
How many cubic Inches in a gallon - ANSWER✔✔-231"
Psi (gauge pressure) at the base of a column of water - ANSWER✔✔-.434 x
height in feet
At what temp is water most dense - ANSWER✔✔-39.2 degrees
Volume of a cylinder - ANSWER✔✔-V=πr²h ( pi X r squared X height
Where is the vacuum breaker located on a flushometer - ANSWER✔✔-After the
valve
How do you test a water systems - ANSWER✔✔-125 psi for 15 minutes
How many water closets are allowed on a 3" stack - ANSWER✔✔-3
2025/2026 EXPERT VERIFIED QUESTIONS WITH
DETAILED ANSWERS| GUARANTEED PASS
How far can a trap arm go 1 1/2" 2" 3" 4" - ANSWER✔✔-5' 6' 8' 10'
What is the maximum water pressure going into a residential dwelling -
ANSWER✔✔-80 psi
What is the smallest drain piping allowed underground - ANSWER✔✔-2"
What's the minimal size vent going through a roof - ANSWER✔✔-2"
How many pounds in a gallon of water - ANSWER✔✔-8.33 lbs
How many gallons in a cubic foot of water - ANSWER✔✔-7.5
How much does a square foot of water weigh - ANSWER✔✔-62.5 lbs
What is the minimal size piping for drainage going through a foundation wall -
ANSWER✔✔-4"
,What is the minimal size water main underground - ANSWER✔✔-3/4"
How far should a dwv vent go through the roof - ANSWER✔✔-18-24"
What is the max temp for a shower head - ANSWER✔✔-112 degrees
What is the maximum distance for a common vent at different levels -
ANSWER✔✔-10"
What is the minimal liquid trap seal - ANSWER✔✔-2"
What must be stamped on the lip of every S.U. Gasket - ANSWER✔✔-ASTM, SV
or XH neoprene, manufactures name
How do you calculate the size of an air gap - ANSWER✔✔-It must be at least
twice the size of the diameter of the drain it serves
(into a receptor, sink, floor drain, or inlet side of a trap)
What is the minimal pounds of grease per gallon of flow - ANSWER✔✔-2 pounds
Minimal size water heater that requires a safe pan - ANSWER✔✔-6 gallons
what is the multiplier for a 45 degree offset - ANSWER✔✔-Rise x 1.414 = offset
Area of a triangle formula - ANSWER✔✔-A=1/2bh (bxh divide by 2)
, What temperature does water boil at - ANSWER✔✔-212 degrees Fahrenheit
What temperature does water freeze at - ANSWER✔✔-32 degrees Fahrenheit
Volume of a rectangle - ANSWER✔✔-L x W x H
Volume of a triangular solid - ANSWER✔✔-Bxh divided by 2 x L
How many gallons in a fixture unit - ANSWER✔✔-7.5
How many cubic Inches in a gallon - ANSWER✔✔-231"
Psi (gauge pressure) at the base of a column of water - ANSWER✔✔-.434 x
height in feet
At what temp is water most dense - ANSWER✔✔-39.2 degrees
Volume of a cylinder - ANSWER✔✔-V=πr²h ( pi X r squared X height
Where is the vacuum breaker located on a flushometer - ANSWER✔✔-After the
valve
How do you test a water systems - ANSWER✔✔-125 psi for 15 minutes
How many water closets are allowed on a 3" stack - ANSWER✔✔-3
