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MASTER PLUMBING WSSC Questions and
Answers (Expert Solutions)
Q: Who is responsible for maintaining the plumbing system in a safe condition?, 🗹🗹:
The owner or owner's agent is responsible.
Q: Before work commences when must a permit be obtained?, 🗹🗹: A permit must be
obtained or a 100% (Double the normal fee) will be charged.
Q: Underground Piping, 🗹🗹: All underground piping shall be left uncovered until
inspected.
Q: Inspector's Authority, 🗹🗹: The inspector has authority to stop work being done
dangerously or unsafely.
Q: Air Gap, 🗹🗹: The vertical distance between the opening of the water supply and
flood level rim of a receptacle.
Q: Branch, 🗹🗹: Any part of the piping system except mains, stacks or risers.
Q: Branch Vent, 🗹🗹: A vent connecting individual vents with a stack vent or vent
stack.
Q: Building Drain, 🗹🗹: The lowest part of a drainage system which receives waste
from soil and waste pipes and connects to the building sewer.
Q: Building Sewer, 🗹🗹: Drainage piping that conveys waste from the building drain
to the public sewer or disposal system.
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Q: Cleanout, 🗹🗹: Access opening in the drainage system used to remove
obstructions.
Q: Combination Fixture, 🗹🗹: Two or three compartment sink drained by a
continuous waste connected to one trap.
Q: Combinate Waste and Vent System, 🗹🗹: Horizontal wet venting system for sinks
and floor drains.
Q: Common Vent, 🗹🗹: A single vent serving as the vent for two fixture drains.
Q: Critical Level, 🗹🗹: Is an elevation mark on a vacuum breaker setting the
minimum elevation device can be installed above the flood level rim of a fixture.
Q: Cross Connection, 🗹🗹: Is an actual or potential tie between potable water and
any source of pollution or contamination.
Q: Developed Length, 🗹🗹: A measurement of piping taken along the centerline of
pipe and fittings
Q: Drain, 🗹🗹: any pipe that conveys waste water in the drainage system.
Q: Indirect Waste, 🗹🗹: Waste pipe that drains through an air gap to the drainage
system.
Q: Individual Vent, 🗹🗹: A pipe installed to vent a fixture trap. It may connect to the
vent system above the fixture or terminate in the open air.
Q: Main, 🗹🗹: Is the primary or principal pipe that drains through an air gap to the
drainage system.
Q: Potable Water, 🗹🗹: Is water that is sufficiently free of impurities to meet public
health standards.
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Q: Rough In, 🗹🗹: Parts of the plumbing system that are installed
prior to the installation of fixtures.
Q: Soil Pipe, 🗹🗹: Is drain pipe conveying sewage containing fecal matter.
Q: Stack Vent, 🗹🗹: Is the extension of a soil or waste stack above the highest fixture
served.
Q: Trap, 🗹🗹: Is a device that provides a water seal to prevent the passage of sewer
gas and allow the passage of waste.
Q: Trap Seal, 🗹🗹: Distance from weir to top of the dip of the trap
Q: Vacuum Breaker, 🗹🗹: Is a backflow preventer that allows air to a vacuum being
pulled on a system.
Q: Vent Stack, 🗹🗹: A vertical vent pipe to provide circulation of air to and from
drainage system
Q: Vertical Pipe, 🗹🗹: Pipe that makes an angle of 45 degrees or more with the
horizontal.
Q: No do this, 🗹🗹: No dangerous, flammable, poisonous, or explosive liquids shall be
deposited in to the drainage system.
Q: Pipes shall be, 🗹🗹: Pipes shall be protected from breakage when passing under or
though walls.
Q: Trenches, 🗹🗹: Trenches installed parallel to footings shall not extend below the
45-degree bearing plane of the wall or footing.
MASTER PLUMBING WSSC Questions and
Answers (Expert Solutions)
Q: Who is responsible for maintaining the plumbing system in a safe condition?, 🗹🗹:
The owner or owner's agent is responsible.
Q: Before work commences when must a permit be obtained?, 🗹🗹: A permit must be
obtained or a 100% (Double the normal fee) will be charged.
Q: Underground Piping, 🗹🗹: All underground piping shall be left uncovered until
inspected.
Q: Inspector's Authority, 🗹🗹: The inspector has authority to stop work being done
dangerously or unsafely.
Q: Air Gap, 🗹🗹: The vertical distance between the opening of the water supply and
flood level rim of a receptacle.
Q: Branch, 🗹🗹: Any part of the piping system except mains, stacks or risers.
Q: Branch Vent, 🗹🗹: A vent connecting individual vents with a stack vent or vent
stack.
Q: Building Drain, 🗹🗹: The lowest part of a drainage system which receives waste
from soil and waste pipes and connects to the building sewer.
Q: Building Sewer, 🗹🗹: Drainage piping that conveys waste from the building drain
to the public sewer or disposal system.
, Page | 2
Q: Cleanout, 🗹🗹: Access opening in the drainage system used to remove
obstructions.
Q: Combination Fixture, 🗹🗹: Two or three compartment sink drained by a
continuous waste connected to one trap.
Q: Combinate Waste and Vent System, 🗹🗹: Horizontal wet venting system for sinks
and floor drains.
Q: Common Vent, 🗹🗹: A single vent serving as the vent for two fixture drains.
Q: Critical Level, 🗹🗹: Is an elevation mark on a vacuum breaker setting the
minimum elevation device can be installed above the flood level rim of a fixture.
Q: Cross Connection, 🗹🗹: Is an actual or potential tie between potable water and
any source of pollution or contamination.
Q: Developed Length, 🗹🗹: A measurement of piping taken along the centerline of
pipe and fittings
Q: Drain, 🗹🗹: any pipe that conveys waste water in the drainage system.
Q: Indirect Waste, 🗹🗹: Waste pipe that drains through an air gap to the drainage
system.
Q: Individual Vent, 🗹🗹: A pipe installed to vent a fixture trap. It may connect to the
vent system above the fixture or terminate in the open air.
Q: Main, 🗹🗹: Is the primary or principal pipe that drains through an air gap to the
drainage system.
Q: Potable Water, 🗹🗹: Is water that is sufficiently free of impurities to meet public
health standards.
, Page | 3
Q: Rough In, 🗹🗹: Parts of the plumbing system that are installed
prior to the installation of fixtures.
Q: Soil Pipe, 🗹🗹: Is drain pipe conveying sewage containing fecal matter.
Q: Stack Vent, 🗹🗹: Is the extension of a soil or waste stack above the highest fixture
served.
Q: Trap, 🗹🗹: Is a device that provides a water seal to prevent the passage of sewer
gas and allow the passage of waste.
Q: Trap Seal, 🗹🗹: Distance from weir to top of the dip of the trap
Q: Vacuum Breaker, 🗹🗹: Is a backflow preventer that allows air to a vacuum being
pulled on a system.
Q: Vent Stack, 🗹🗹: A vertical vent pipe to provide circulation of air to and from
drainage system
Q: Vertical Pipe, 🗹🗹: Pipe that makes an angle of 45 degrees or more with the
horizontal.
Q: No do this, 🗹🗹: No dangerous, flammable, poisonous, or explosive liquids shall be
deposited in to the drainage system.
Q: Pipes shall be, 🗹🗹: Pipes shall be protected from breakage when passing under or
though walls.
Q: Trenches, 🗹🗹: Trenches installed parallel to footings shall not extend below the
45-degree bearing plane of the wall or footing.
