UA STAR plumbing Exam | Atcual Questions with 100%
Correct Answers | Verified | Latest Update 2026
1. If a gas equipment installation is found to be only 2 feet away from the
building, what action should the journeyman plumber/gas-fitter take?
Reposition the equipment to meet the required distance.
Install additional safety measures without repositioning.
Notify the building owner and document the finding.
Leave it as is since it is within acceptable limits.
2. The LPG pressure regulator shall deliver gas, under varying appliance loads,
at a pressure not in excess of water column.
12 inches
16 inches
2 inches
14 inches
3. _____-vent is known as a single stack sanitary drainage system employing the
use of aerator and de-aerator fittings to regulate pressure changes within the
DWV-system to protect trap seals.
Loop
Yoke
So
Continuous
4. If a plumber is installing CPVC piping in a residential setting and the hot
water tank is located 18 inches from the planned installation site, what should
, the plumber do to comply with the plumbing code?
Relocate the CPVC piping to be at least 24 inches away from the hot
water tank.
Install insulation around the CPVC piping to protect it from heat.
Proceed with the installation as planned since 18 inches is acceptable.
Use a different type of piping that does not have a distance
requirement.
5. Describe the significance of the developed-length limit for a vent serving a
pressure regulator in plumbing code.
The developed-length limit is irrelevant to gas safety.
The developed-length limit is determined by the size of the gas meter.
The developed-length limit only applies to water systems, not gas.
The developed-length limit ensures proper venting and prevents
pressure issues in the gas system.
6. Describe the significance of the unthreaded portion of schedule-40 steel gas
piping when it penetrates a wall.
The unthreaded portion is irrelevant to safety regulations.
The unthreaded portion must be longer than the threaded portion.
The unthreaded portion can be any length as long as it is steel.
The unthreaded portion must be at least 1-inch to ensure proper
sealing and safety compliance.
,7. What is the minimum distance in inches that CPVC pipe and fittings must be
located from any connection to a hot water tank according to MGL. c. 142, §
17?
18
20
30
12
24
8. Describe the purpose of a reduced pressure backflow preventer (RPBP) in
plumbing systems.
The RPBP prevents contaminated water from flowing back into the
potable water supply.
The RPBP filters impurities from the water supply.
The RPBP regulates water pressure in plumbing systems.
The RPBP is used to measure water flow rates.
9. Describe the relationship between the 'rise' and 'run' in the context of an
offset pipe.
The 'rise' is only relevant in vertical pipes, while the 'run' applies to
horizontal pipes.
The 'rise' and 'run' are interchangeable terms in plumbing.
The 'rise' refers to the angle of the pipe, and the 'run' is the total length
of the pipe.
The 'rise' is the vertical height of the slanted portion, while the 'run'
is the horizontal distance it covers.
, 10. What is the primary purpose of aerator and de-aerator fittings in a plumbing
system?
To provide additional support to the plumbing structure
To regulate pressure changes within the DWV-system to protect
trap seals
To increase water flow in the drainage system
To filter contaminants from the water supply
11. A hot water system in a multistory building has piping that travels vertical up
the floors. If I had a pressure gauge on each level I would notice the
pressure in the pipe _________ as I move up the floors.
goes down
does not change
goes up
is 12 kPa
12. If a plumber needs to install a new drainage system that requires an offset,
which part of the piping system will they need to ensure is correctly slanted
to facilitate proper drainage?
Rise
Run
Drop
Vent
13. Describe the importance of rotating the pipe when joining ABS or PVC pipe
to a fitting with solvent cement.
Correct Answers | Verified | Latest Update 2026
1. If a gas equipment installation is found to be only 2 feet away from the
building, what action should the journeyman plumber/gas-fitter take?
Reposition the equipment to meet the required distance.
Install additional safety measures without repositioning.
Notify the building owner and document the finding.
Leave it as is since it is within acceptable limits.
2. The LPG pressure regulator shall deliver gas, under varying appliance loads,
at a pressure not in excess of water column.
12 inches
16 inches
2 inches
14 inches
3. _____-vent is known as a single stack sanitary drainage system employing the
use of aerator and de-aerator fittings to regulate pressure changes within the
DWV-system to protect trap seals.
Loop
Yoke
So
Continuous
4. If a plumber is installing CPVC piping in a residential setting and the hot
water tank is located 18 inches from the planned installation site, what should
, the plumber do to comply with the plumbing code?
Relocate the CPVC piping to be at least 24 inches away from the hot
water tank.
Install insulation around the CPVC piping to protect it from heat.
Proceed with the installation as planned since 18 inches is acceptable.
Use a different type of piping that does not have a distance
requirement.
5. Describe the significance of the developed-length limit for a vent serving a
pressure regulator in plumbing code.
The developed-length limit is irrelevant to gas safety.
The developed-length limit is determined by the size of the gas meter.
The developed-length limit only applies to water systems, not gas.
The developed-length limit ensures proper venting and prevents
pressure issues in the gas system.
6. Describe the significance of the unthreaded portion of schedule-40 steel gas
piping when it penetrates a wall.
The unthreaded portion is irrelevant to safety regulations.
The unthreaded portion must be longer than the threaded portion.
The unthreaded portion can be any length as long as it is steel.
The unthreaded portion must be at least 1-inch to ensure proper
sealing and safety compliance.
,7. What is the minimum distance in inches that CPVC pipe and fittings must be
located from any connection to a hot water tank according to MGL. c. 142, §
17?
18
20
30
12
24
8. Describe the purpose of a reduced pressure backflow preventer (RPBP) in
plumbing systems.
The RPBP prevents contaminated water from flowing back into the
potable water supply.
The RPBP filters impurities from the water supply.
The RPBP regulates water pressure in plumbing systems.
The RPBP is used to measure water flow rates.
9. Describe the relationship between the 'rise' and 'run' in the context of an
offset pipe.
The 'rise' is only relevant in vertical pipes, while the 'run' applies to
horizontal pipes.
The 'rise' and 'run' are interchangeable terms in plumbing.
The 'rise' refers to the angle of the pipe, and the 'run' is the total length
of the pipe.
The 'rise' is the vertical height of the slanted portion, while the 'run'
is the horizontal distance it covers.
, 10. What is the primary purpose of aerator and de-aerator fittings in a plumbing
system?
To provide additional support to the plumbing structure
To regulate pressure changes within the DWV-system to protect
trap seals
To increase water flow in the drainage system
To filter contaminants from the water supply
11. A hot water system in a multistory building has piping that travels vertical up
the floors. If I had a pressure gauge on each level I would notice the
pressure in the pipe _________ as I move up the floors.
goes down
does not change
goes up
is 12 kPa
12. If a plumber needs to install a new drainage system that requires an offset,
which part of the piping system will they need to ensure is correctly slanted
to facilitate proper drainage?
Rise
Run
Drop
Vent
13. Describe the importance of rotating the pipe when joining ABS or PVC pipe
to a fitting with solvent cement.
