interNachi Residential Plumbing
Overview Exam Questions and
Answers 100% Pass
What are the four defects of plumbing? - ANSWER✔✔-a leak;
inadequate water supply;
water contamination;
and/or the incorrect installation of a component.
T/F: This course only addresses code-related violations regarding plumbing fixtures. -
ANSWER✔✔-False
"Plumbing" comes from the Latin word "plumbum," which means ___________. -
ANSWER✔✔-lead
T/F: Contamination can affect water's potability. - ANSWER✔✔-True
According to the InterNACHI Standards of Practice, the inspector is required to _______
all the toilets. - ANSWER✔✔-flush
T/F: The inspector is required to light or ignite pilot lights. - ANSWER✔✔-False
Copyright ©SOPHIABENNETT 2025 ACADEMIC YEARALL RIGHTS RESERVED. Page 1/39
,If a home inspector observes a fuel storage tank, the inspector _____ describe that in the
report. - ANSWER✔✔-must
Define ABS (acrylonitrile butadiene styrene): - ANSWER✔✔-Rigid black plastic pipe
used for drain, waste and vent lines.
Define access cover - ANSWER✔✔-Removable plate that permits access to a pipe or
pipe fitting for the purpose of inspection, maintenance, repair or replacement.
Define access panel - ANSWER✔✔-An opening in the wall or ceiling near a fixture that
allows access for servicing the plumbing/electrical system.
Define accessible: - ANSWER✔✔-In the opinion of the inspector, can be approached or
entered safely without difficulty, fear or danger.
Define activate - ANSWER✔✔-To turn on, supply power, or enable systems, equipment
or devices to become active by normal operating controls. Examples include turning on
the gas or water supply valves to the fixtures and appliances, and activating electrical
breakers or fuses.
Define adaptor - ANSWER✔✔-A fitting that unites different types of pipe together,
such as ABS to cast-iron pipe.
Define aerator - ANSWER✔✔-An apparatus that mixes air into flowing water. It is
screwed onto the end of a faucet spout to help reduce splashing.
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,Define air-admittance valve - ANSWER✔✔-One-way valve designed to admit air into
the plumbing system to protect the traps from siphonage; a device used as an
alternative to vents for individual fixtures and branches in the plumbing drainage
system.
Define air chamber - ANSWER✔✔-A vertical, air-filled pipe that prevents water
hammer by absorbing pressure when the water is shut off at a faucet or valve.
Define air gap (drainage) - ANSWER✔✔-The unobstructed vertical distance through
free atmosphere between the outlet of the waste pipe and the flood-level rim of the
receptacle into which the waste pipe is discharged.
Define air gap (water distribution) - ANSWER✔✔-The unobstructed vertical distance
through free atmosphere between the lowest opening from any pipe or faucet that
supplies water to a receptacle (sink, tank, fixture, or other device) and the flood-level
rim of that receptacle.
Define anti-scald - ANSWER✔✔-A valve that restricts water flow to help prevent burn
injuries. See pressure-balancing valve and thermostatic valve. In some areas, plumbing
codes require anti-scald valves.
Define anti-siphon - ANSWER✔✔-A device that prevents wastewater from being
drawn back into supply lines and possibly contaminating the water supply.
Define aperture - ANSWER✔✔-An opening in a pipe.
Copyright ©SOPHIABENNETT 2025 ACADEMIC YEARALL RIGHTS RESERVED. Page 3/39
, Define appliance - ANSWER✔✔-An apparatus, device, or equipment operated by use
of electricity or fuel gas to produce heat, light, power, refrigeration, or air conditioning.
Define approved - ANSWER✔✔-Accepted by the code official, third-party agency,
authority having jurisdiction (AHJ), or conforming to a standard such as ANSI.
Define back-pressure - ANSWER✔✔-Pressure created in a non-potable system in excess
of the water supply mains causing backflow. Back-pressure can be created by
mechanical means (such as a pump), by static head pressure (including an elevated
tank), or by thermal expansion from a heat source (such as a water heater).
Define back-siphonage - ANSWER✔✔-The backflow of water caused by system
pressure falling below atmospheric pressure. Atmospheric pressure supplies the force
that reverses the flow.
Define backflow - ANSWER✔✔-The flow of liquids in potable water distribution piping
in reverse of their intended path. There are two types of pressure conditions that cause
backflow: back-siphonage and back-pressure.
Define backflow preventer - ANSWER✔✔-A device or means to prevent backflow into
the potable water supply.
Define basket strainer - ANSWER✔✔-Basket-shaped strainer with holes allowing water
to drain while catching food or other solids; can also be closed to fill the sink with
water.
Copyright ©SOPHIABENNETT 2025 ACADEMIC YEARALL RIGHTS RESERVED. Page 4/39
Overview Exam Questions and
Answers 100% Pass
What are the four defects of plumbing? - ANSWER✔✔-a leak;
inadequate water supply;
water contamination;
and/or the incorrect installation of a component.
T/F: This course only addresses code-related violations regarding plumbing fixtures. -
ANSWER✔✔-False
"Plumbing" comes from the Latin word "plumbum," which means ___________. -
ANSWER✔✔-lead
T/F: Contamination can affect water's potability. - ANSWER✔✔-True
According to the InterNACHI Standards of Practice, the inspector is required to _______
all the toilets. - ANSWER✔✔-flush
T/F: The inspector is required to light or ignite pilot lights. - ANSWER✔✔-False
Copyright ©SOPHIABENNETT 2025 ACADEMIC YEARALL RIGHTS RESERVED. Page 1/39
,If a home inspector observes a fuel storage tank, the inspector _____ describe that in the
report. - ANSWER✔✔-must
Define ABS (acrylonitrile butadiene styrene): - ANSWER✔✔-Rigid black plastic pipe
used for drain, waste and vent lines.
Define access cover - ANSWER✔✔-Removable plate that permits access to a pipe or
pipe fitting for the purpose of inspection, maintenance, repair or replacement.
Define access panel - ANSWER✔✔-An opening in the wall or ceiling near a fixture that
allows access for servicing the plumbing/electrical system.
Define accessible: - ANSWER✔✔-In the opinion of the inspector, can be approached or
entered safely without difficulty, fear or danger.
Define activate - ANSWER✔✔-To turn on, supply power, or enable systems, equipment
or devices to become active by normal operating controls. Examples include turning on
the gas or water supply valves to the fixtures and appliances, and activating electrical
breakers or fuses.
Define adaptor - ANSWER✔✔-A fitting that unites different types of pipe together,
such as ABS to cast-iron pipe.
Define aerator - ANSWER✔✔-An apparatus that mixes air into flowing water. It is
screwed onto the end of a faucet spout to help reduce splashing.
Copyright ©SOPHIABENNETT 2025 ACADEMIC YEARALL RIGHTS RESERVED. Page 2/39
,Define air-admittance valve - ANSWER✔✔-One-way valve designed to admit air into
the plumbing system to protect the traps from siphonage; a device used as an
alternative to vents for individual fixtures and branches in the plumbing drainage
system.
Define air chamber - ANSWER✔✔-A vertical, air-filled pipe that prevents water
hammer by absorbing pressure when the water is shut off at a faucet or valve.
Define air gap (drainage) - ANSWER✔✔-The unobstructed vertical distance through
free atmosphere between the outlet of the waste pipe and the flood-level rim of the
receptacle into which the waste pipe is discharged.
Define air gap (water distribution) - ANSWER✔✔-The unobstructed vertical distance
through free atmosphere between the lowest opening from any pipe or faucet that
supplies water to a receptacle (sink, tank, fixture, or other device) and the flood-level
rim of that receptacle.
Define anti-scald - ANSWER✔✔-A valve that restricts water flow to help prevent burn
injuries. See pressure-balancing valve and thermostatic valve. In some areas, plumbing
codes require anti-scald valves.
Define anti-siphon - ANSWER✔✔-A device that prevents wastewater from being
drawn back into supply lines and possibly contaminating the water supply.
Define aperture - ANSWER✔✔-An opening in a pipe.
Copyright ©SOPHIABENNETT 2025 ACADEMIC YEARALL RIGHTS RESERVED. Page 3/39
, Define appliance - ANSWER✔✔-An apparatus, device, or equipment operated by use
of electricity or fuel gas to produce heat, light, power, refrigeration, or air conditioning.
Define approved - ANSWER✔✔-Accepted by the code official, third-party agency,
authority having jurisdiction (AHJ), or conforming to a standard such as ANSI.
Define back-pressure - ANSWER✔✔-Pressure created in a non-potable system in excess
of the water supply mains causing backflow. Back-pressure can be created by
mechanical means (such as a pump), by static head pressure (including an elevated
tank), or by thermal expansion from a heat source (such as a water heater).
Define back-siphonage - ANSWER✔✔-The backflow of water caused by system
pressure falling below atmospheric pressure. Atmospheric pressure supplies the force
that reverses the flow.
Define backflow - ANSWER✔✔-The flow of liquids in potable water distribution piping
in reverse of their intended path. There are two types of pressure conditions that cause
backflow: back-siphonage and back-pressure.
Define backflow preventer - ANSWER✔✔-A device or means to prevent backflow into
the potable water supply.
Define basket strainer - ANSWER✔✔-Basket-shaped strainer with holes allowing water
to drain while catching food or other solids; can also be closed to fill the sink with
water.
Copyright ©SOPHIABENNETT 2025 ACADEMIC YEARALL RIGHTS RESERVED. Page 4/39
