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  • In drainage venting, which vent extends above the highest drain on the stack to allow air entry?
  • A waste pipe that discharges into an approved open connection is called what?
  • What is the maximum distance between manholes on underground drainage lines with a diameter of 10 inches or larger?
  • Indirect waste to sanitary waste line maximum developed length is how many feet?
  • Tuberculation is a corrosion-related condition inside piping. It most directly affects which part of the pipe?
  • A protective strainer is required on the upstream side of the first check valve unless it is what type of system?
  • Which type of drain is designed to collect surface water around a building and prevent entry into the interior?
  • What is the minimum size specified for any combination waste and vent drainage line, in inches?
  • Which type of venting applies only to floor drains which depend on siphonage for proper operation?
  • Which section of a building's drainage system is located at the lowest point and receives discharge from soil, waste, and other interior drain pipes?
  • For a 3 inch pipe, the maximum distance from fixture trap to vent is?
  • Where is an escutcheon ring used?
  • Which of the following is NOT an acceptable bidet water configuration?
  • Lavatory minimum trap size is specified as?
  • Which system is specifically designed to remove rainwater and ground water from a building site?
  • Which backflow prevention device is used in plumbing to prevent backflow of non-potable liquids into the drinking water system?
  • What type of waste includes harmful substances such as ethylene glycol, hydrocarbons, oil, refrigerants, or hydrazine?
  • For a 1 1/2 inch pipe, the maximum distance from fixture trap to vent is?
  • For a vertically installed cast iron pipe, what is the maximum allowable distance between supports?
  • What is the name of a water supply pipe that extends vertically one full story or more to supply water to main branches or a group of fixtures?
  • Which professional is qualified to field test all backflow prevention devices?
  • The tube attached to the ballcock and discharging into the toilet tank is designed for what purpose?
  • What is the maximum drainage fixture units for a horizontal branch using a 4-inch pipe?
  • Which outdoor fixture provides a direct hose connection to the water supply?
  • Which two parts of a trap are used to measure the depth of the trap seal?
  • What is the maximum developed length for an indirect waste to any sanitary waste line?
  • Which device isolates a heat exchanger when pressure drops below a preset level to protect water quality?
  • What is the purpose of the hole near the top end of a dip tube in a domestic water heater?
  • What fitting is acceptable for connecting two horizontal drain lines?
  • How many gallons per minute are equivalent to one fixture unit?
  • Which gas is lighter than air in plumbing?
  • What is a vent that permits circulation of air in between drainage and vent systems?
  • A vent connecting one or more individual vents with a vent stack is called what?
  • What is the minimum size of a gas and oil interceptor?
  • Floor Drain minimum trap size is specified as?
  • What is the primary function of the venting system in a drainage setup?
  • Who is qualified to field test all backflow prevention devices?
  • The two parts of a trap used to measure the depth of the trap seal?
  • What is the drainage fixture units for a urinal?
  • What type of drain is placed outside a basement entryway or paved driveway?
  • Which type of gas used in plumbing is lighter than air?
  • Which piping joint is designed to connect two sections while allowing easy disassembly without disturbing adjacent piping?
  • What term describes the measured length along the center line of the pipe including its fittings?
  • Where is the corporation stop located on a water service line?
  • Which section of piping is located at the lowest point of a building's drainage system and receives discharges from interior drainage?
  • An escutcheon ring is typically used around what feature?
  • True or False: The minimum constant pressure on the discharge side of the water meter is 20 psi.
  • True or False: The maximum distance between manholes on underground drainage lines that are 10 inches in diameter or larger is 150 feet.
  • What fitting is used to secure a wall-mounted water closet?
  • Which style of water closet typically uses the least water in its trap?
  • What is the minimum size of a cleanout serving a 4-inch drain line?
  • Which statement about saddle valves is true?
  • What is the name of the plumbing inspection conducted before covering walls and floors?
  • Which type of sewer system is used for conveying rain water, surface water, ground water, or condensation from the building storm drain to an approved point of discharge?
  • Where must the pump be installed on a whirlpool type bathtub?
  • For a 1 1/4 inch pipe, the maximum distance from fixture trap to vent is?
  • What is the maximum Drainage Fixture Units (DFUs) allowed on a 2-inch horizontal waste line?
  • Corrosion inside pipes can cause tuberculation, which forms small hemispherical lumps on the pipe walls. What is this condition called?
  • In plumbing, if piping, fixtures, or equipment would interfere with the operation of windows or doors, what action is required?
  • A pipe making an angle greater than 45 degrees from horizontal is called what?
  • What is required for a water piping system with a pressure exceeding 80 psi?
  • What is the minimum height above the roof that a vent pipe must extend?
  • Which factor is considered when sizing vent piping?
  • To which side of the trap must the overflow pipe connect?
  • Which of the following is the correct minimum vent pipe height above the roof?
  • What is the minimum clearance required in front of a cleanout?
  • Which device prevents excessive vacuum in a pressure vessel?
  • What is the minimum size for the vent for a single water closet?
  • Bath Tub minimum trap size is required to be what size?
  • Which test is used to identify defects in the drainage system?
  • Which vent type is used to relieve pressure by allowing air movement between drainage and vent systems?
  • What is the maximum vertical distance between a fixture outlet and the trap weir?
  • A 22.5-degree bend represents which fraction of a circle?
  • For a 4 inch pipe, the maximum distance from fixture trap to vent is?
  • Which fitting is acceptable for connecting two horizontal drain lines?
  • Faucet washers requiring replacement in a kitchen sink faucet may indicate wear on which part of the faucet?
  • Clothes Washer minimum trap size is specified as?
  • Which term designates the section of the fixture drain that runs from the trap to the vent?
  • What is the minimum trap size for a urinal?
  • Water closet bowls for public use shall be of what design?
  • True or False: A temperature and pressure relief valve shall discharge to the outside atmosphere if a floor drain is accessible.
  • The substance used to prevent oxide formation on freshly cleaned copper before soldering or brazing is called what?
  • In a high-pressure water system, which component is used to reduce incoming pressure?
  • What is the unobstructed open edge of a fixture called?
  • Which waste is known to include toxic liquids such as ethylene glycol and refrigerants?
  • Clothes Washer Drainage Fixture Units (DFU) value is?
  • What is the measurement called when you measure from the inside wall of a pipe to the opposite inside wall?
  • What type of joint can be disassembled and reassembled without removing any adjacent piping?
  • What type of faucet is used for drawing water from a buried pipe?
  • What type of vent receives the vapors from non-pressure sterilizers or the exhaust vapors from pressure sterilizers and conducts them to the outside atmosphere?
  • Which term describes joining plastic pipe to fittings by chemical fusion?
  • Under what circumstances may a saddle valve be used to connect an icemaker or refrigeration line?
  • Which value is correct for gallons per minute per fixture unit?
  • What is the minimum constant water pressure on the discharge side of the water meter?
  • What phenomenon occurs when there is a sudden deceleration of water flow in a closed conduit?
  • A magnesium anode rod is typically installed in which appliance?
  • Which vent rises as near as possible to or above the highest water level in the fixture vented before connecting to the stack or main vent?
  • What is the maximum distance allowed between trapped openings on a trench drains used to carry waste to gas and oil interceptors?
  • A buried water supply is accessed by which device designed to deliver water from the street main?
  • Peppermint test is used to find defects in which system?
  • What is the lowest part of the internal cross section of a pipe called?
  • The finished exterior size of a shower in a single-family home must be at least how many inches?
  • Which device in venting system helps prevent back-pressure and siphonage, protecting traps?
  • For a 2 inch pipe, the maximum distance from fixture trap to vent is?
  • Which type of vent connects a drain pipe through a fitting at an angle less than 45 degrees?
  • What portion of a fixture drain lies between the trap and its vent?
  • What device controls the water temperature maintained in a hot water tank for single-family use?
  • Which part of the waste stack extends above the highest horizontal drain connected to the stack?
  • Water Heaters, Water Coolers, Drinking Fountains, Heat Exchangers, and Water Treatment Equipment belong to which category?
  • All showers and shower-baths must be provided with what type of device?
  • Which valve operates by screwing a disc against a seat?
  • What is the drainage fixture units for a water closet?
  • What type of receptacle receives sanitary or storm waste located below the normal grade level of the gravity system?
  • What is the minimum trap size for a shower?
  • At which trap size does lavatory DFU increase to 2 DFU?
  • What process fuses plastic pipe and fittings together chemically?
  • Copper Type M is allowed to be installed for water piping in which location?
  • Piping and fixtures for standards not adopted by the Code may be installed with permission from which agency?
  • What is the minimum height above the flood rim at which a relief vent shall connect to the vent stack?
  • What is the minimum trap size for a water closet?
  • What is the minimum finished exterior size of a shower in a single-family home?
  • Which type of waste contains human excrement and liquid waste?
  • Which device is used on a sewage ejector discharge line to prevent backflow into the building?
  • What is the minimum trap size for a kitchen sink?
  • To properly tighten a mission band or Fernco coupling, the torque wrench should be set to which pressure?
  • Bath tub Drainage Fixture Units (DFU) value is specified as how many DFU?
  • Backfill height 18 inches? The trench backfilled in 6" layers to how many inches above the top crown?
  • Which device is used to join two pipe sections and allow disassembly without cutting?
  • Where is copper type M allowed to be installed for water piping?
  • Which type of potable water supply provides water for drinking, culinary, and sanitary purposes for an owner-occupied single-family dwelling?
  • What term describes reverse flow in a water supply caused by a vacuum?
  • Which fitting is used to secure a wall-mounted toilet?
  • Water Heaters, Water Coolers, Drinking Fountains, Heat Exchangers, and Water Treatment Equipment are examples of which category?
  • What is the maximum number of water closets on a 3-inch horizontal branch drain?
  • Which type of device or fixture receives the discharge from indirect waste pipes?
  • A 45-degree bend represents which fraction of a circle?
  • Which faucet drains water from the bottom of a water heater?
  • Which organization lists the approved standards for gas-fired storage type water heaters?
  • Minimum vent size for a 4-inch trap?
  • Which device protects water quality, is failsafe in design, and isolates a heat exchanger when the water pressure and exchange medium drop below a preset level?
  • Which device directly transfers heating energy to a space by radiation or gravity convection?
  • In which type of plumbing fixture may a magnesium rod be installed?
  • A waste pipe that discharges into and through an approved open connection is called what?
  • The discharge line on a sewage ejector line requires which device?
  • The trench shall be backfilled in 6" layers to how many inches above the top crown of the piping?
  • Which factors affect vent size?
  • Backflow devices must be installed in a way that they are protected from which conditions?
  • In residential plumbing, which piping system includes the water service and all potable piping to supply a single dwelling?
  • What is the maximum temperature of any water discharging into any part of the drainage system?
  • The Durham System is defined as a waste system where all piping is threaded and uses recessed fittings.
  • Minimum vent size for a 4-inch trap?
  • What is the drainage fixture units for a shower?
  • What is the drainage fixture units for a kitchen sink?
  • What is the required trap seal depth for above-ground fixtures?
  • Which fitting is required for making the yoke vent intersection?
  • What are devices for supporting and securing pipes, fixtures, and equipment to walls, ceilings, floors, or other structural members called?
  • Which term describes the network that provides potable water to a single dwelling including the service line?
  • What happens when different materials are joined in a water piping system?
  • All vent and branch lines shall be installed so that they drain where?
  • What is the name of the point at which impounded liquid will overflow a fixture or receptacle?
  • Floor Drain Drainage Fixture Units (DFU) value is?
  • True or False: A temperature and pressure relief valve shall discharge to the outside atmosphere if a floor drain is not accessible.
  • A 90-degree bend represents which fraction of a circle?
  • What chemical prevents oxides on copper before soldering?
  • True or False: A 3-inch horizontal branch drain may accommodate two water closets.
  • In plumbing, what term describes the rapid rise in pressure caused by a sudden stop in flow in a pipe?
  • Tanks flushing more than one urinal require what type of operation?
  • For a lavatory, what is the Drainage Fixture Units at a 1-1/4 inch trap size?
  • True or False: Mechanical Devices shall not be installed in the plumbing vent system except for single family structures where the homeowner is doing their own plumbing work.
  • Which type of sewer system is not directly controlled by a public authority?
  • What is the minimum pipe size for a maximum size of any combination waste and vent drainage line?
  • What is the minimum time required for an acceptable test of the water piping system?
  • What is the function of the siphon breaker hole near the top of a dip tube?
  • Which valve type meets the requirement for shower mixing to regulate temperature and pressure?
  • What is created when air pressure drops below atmospheric pressure?
  • Which faucet is designed to connect a garden hose to the water supply?
  • In plumbing terminology, what is the vertical water supply pipe that carries water to main branches called?
  • True or False: The vent for a single water closet is at least 2 inches in diameter.
  • What is the maximum drainage fixture units for a horizontal branch using a 2-inch pipe?
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