ABS (Acrylonitrile Butadiene Styrene): A pipe made of plastic that is used for vents and drains.

Absorption Field: A seeping field that is made to receive effluent from a septic tank.

Adjustable Hot Limit Stop: Limits the amount of hot water in showers and single control faucets to prevent scalding. It does this by limiting how far the control can be turned in the hot direction.

Aerator: An insert similar to a screen that is screwed onto the outlet of a faucet. It limits splashing by mixing flowing water with the air.

Air Admittance Valve: Equalizes pressure by allowing air to get into a pipe. The fixture trap's seal of water is preserved. It is a replacement for a standard vent.

Air Gap: A vertical opening that is unobstructed in a drainage system that is located between a waste line's lowest opening and the device's flood level into which it empties. Backflow contamination is prevented.

Auger: A rod that is bendable with an end that is curved. Plumbers use this to remove toilet trap clogs.

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Back Pressure: Piping system pressure that the flow of water resists.

Back Flow: Water from one system backs up into a section of the primary distribution system. This is usually caused by siphoning.

Back Flow Preventer: A mechanism designed to prevent back flow, particularly in a water supply that is potable. It is required for kitchen sprayers, pullout faucet spouts, handheld showers and sprinkler systems.

Backup The clogging of a drain causes an overflow.

Baffle An object that slows down the flow, or changes the direction of water, gases or air when it is inserted into an appliance.

Balancing Valve: A valve in a water heater that balances the distribution of heat and controls the flow of water to various locations.

Ball Check Valve: A valve that stops flow in a single direction by using a ball as a seal that is placed against a seat.

Ball Joint: An assembly in a shower that is shaped like a sphere. It enables the head to rotate and pivot.

Ballcock: A gravity-operated toilet's valve that controls the tank getting refilled. The float is connected to it by a metal or plastic arm. Once the toilet is flushed, the toilet will continue to fill up until the valve is shut off by the float rising to a high enough level.

Bidet: A personal hygiene plumbing fixture that looks similar to a toilet. It consists of a sprayer, faucet and a basin.

Bleed: The process of opening a valve at the end of a pipe to drain excess air from it.

Blowbag: Also called a blowfish. A device used to clean drains. It consists of a bladder made of rubber that has a nozzle connected to one end and a hose on the other. Once the device is connected to a water hose, it is placed into a drainpipe that has been clogged. When water starts to flow, the blowbag grips the pipe by expanding. Bursts of water get released through the nozzle. Water is forced through the pipe and the blockage is removed.

Blowdown: Partial draining or venting of a boiler's water side. It is done to eliminate or reduce the amount of contaminants.

Boiler: A tank that is sealed and is used for turning water to steam. The steam is then used for power or heat.

Bonnet: A compression valve assembly's top section. The valve is held in place by the bonnet when it is tightened against a valve seat located on the assembly's opposite end.

Brackish Water: Water that has a level of bacteria of 1,000 to 15,000 ppm of dissolved solids.

Burst Pressure: The amount of internal pressure that will result in the failing of a piece of tubing.

Branch Drain: A drain plumbing fixture that connects to the primary drain line.

Bushing: A fitting that connects different sized pipes by threading on the inside and outside.

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Cleanout Plug: A plug that is located in a drain pipe or trap that allows access so blockages can be cleared.

Closet Bend: A waste pipe fitting that is curved. It connects the drain to the closet flange.

Closet Flange: Also called the floor flange. A ring that is used to anchor a toilet to a floor. It is connected to the closet bend.

Compression fitting: Used to connect pipe or tubing. A nut and a ferrule or sleeve are placed over a tube made of plastic or copper. When the nut is tightened, it is tightly compressed around the tube. This forms a positive grip and seal with no soldering being required.

Coupling: A fitting that is short and used for the joining of two pieces of pipe.

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Dam: A barrier located in a toilet's trapway that controls a toilet bowl's level of water.

Diaphragm: A membrane located in a valve that is flexible. It regulates the flow of water from the supply lines by deflecting down onto the valve body's rigid area. This eliminates the possibility of the valve having debris build up inside of it.

Diffuser: A device that increases the static pressure and reduces the velocity of a fluid by passing through a system.

Dip Tube: The tube that sends cold water to the bottom of a water heater's tank.

Diverter: A valve on a faucet that redirects water from the faucet in the tub to the shower head.

Dope: A lubricant that plumbers use on the thread of pipes.

Drain-Waste-Vent-System: A system of pipes that vents the drain system and drains wastewater from a bathroom.

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Effluent: Liquid waste from a septic system.

Elbow: A fitting that is curved. It is normally 45 degrees or 90 degrees and it is used to change a pipe runs direction.

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Fitting: Any part that connects two pipe sections together, such as bends, couplings and elbows.

Fixture: Anything that discharges or accepts wastewater or regular water, such as tubs, toilets, sinks or faucets.

Flange: The edge or rim at a pipe shaft's end that helps to connect it to a different pipe or anchor it to a surface.

Flapper: A flap made of rubber with a ball at the end. Located at the bottom of a toilet tank, the toilet flushes when the flapper is lifted and stops the refilling process when it is lowered to seal the tank. It enables the flow of water from the tank to the bowl.

Flex Coupling: A fitting made of rubber that utilizes metal band clamps to connect to the end of the pipes. These are primarily used to connect DWV pipe sections. However, it can also connect PVC to cast iron or clay pipe.

Flow Control Valve: A device that is made to lower the amount of water flow that is directed towards a plumbing fixture. It is frequently used to lower operating costs and increase productivity.

Flow Rate: The measuring of the flow of water through a plumbing system in gallons per hour (GPH) or gallons per minute (GPM).

Float Ball: A device that floats and is attached to the ballcock on the inner part of the toilet's tank. It turns on and shuts off the ballcock.

Flushometer: Valve in the toilet that turns off automatically after a specific amount of water has flowed into the toilet. These are most often installed in toilets that are commercial grade.

Flux: A substance similar to jelly that is used to solder fittings and pipes made of copper. The application takes place prior to the soldering for oxidation prevention and to help in the bonding process.

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Galvanizing: As a means of providing protection from corrosion, a coating of zinc is applied to the finished product. Electrolytic deposition or hot dipping can both be used to apply the coating.

Gasket: A device that is flat and made of rubber or fiber. It creates a seal between joints made of metal that is watertight.

Gate: This device allows control of the flow in a tunnel, pipe or conduit.

Gate Diverter: The lever that pops up on the faucet of a tub that activates the diverter valve.

Gauge: Stainless steel thickness that is frequently used regarding the quality levels on specific types of sinks and lavatories. Stainless steel sinks that are 10 and 20-gauge are subjected to several buffing and polishing sessions to make sure the finish is stunning.

GPF: Gallons per flush. The water flow rate that is used to regulate and measure flush valves and toilets. There is now a law that requires 1.6 GPF as the maximum. In the past, toilets frequently were allowed a GPF of 3.5.

Gravity Operated Toilet: A toilet that uses water's natural downward pressure in the tank to effectively flush the toilet.

Gray Water: Waste water that is generated from fixtures excluding toilets.

Grease Trap: Grease is captured in this device as it enters a system before it has a chance to get to any of the sewer lines. It is commonly used in businesses such as cafeterias or restaurants.

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Hard Water: Water that is natural and contains various levels of impurities. Traditional hardness is used to measure dissolved solids, minerals or calcium in a solution that are measured in parts per million. The normal range for hard water is 100 to 250 ppm.

Hanger: A device that can help to support pipes.

Horizontal Branch: Drain pipes that are lateral and go from the plumbing fixtures to a waste stack that is located in the soil or in a building.

Horizontal Run: The distance horizontally between where fluid goes into a pipe and where it exits.

Hose Bib: A faucet that is outdoors. Washing machines have water supplied to them by a hose bib.

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ID: Inside diameter. How a pipe's inside width is measured.

Impeller: A wheel that rotates and has vanes. It is located on the inside of a centrifugal pump. Fluids are drawn in and forced to the discharge outlet under pressure as the wheel rotates at a high rate of speed.

Instantaneous Water Heater: A water heater that is able to heat water when it is flowing through the coil of a heat exchanger.

Interceptor: A device that is used for the separation of oil and grease from drainage systems.

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kPa: A metric unit for pressure. 100 kPa = one atmosphere.

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L Tubing: A copper tubing industry standard that is defined by the thickness of the tube wall. It is identified by a stripe that is blue. The copper tube that is type L has a thickness that is 50 percent more than type M.

Leach Lines: Pipes that are used to transport effluent to the leach field from the septic system. The leach field is a soil area that is porous where waste that is treated gets emptied out.

Low Consumption Toilet: Sometimes called a water-saving toilet. A type of toilet that is made to use a maximum of 1.6 gallons of water when it is flushed.

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M Tubing: A copper tubing industry standard that is defined by the thickness of the tube wall. It is identified by a stripe that is red.

Main: The primary artery of the drain or supply system that connects to all of the branches. In a vent system, it is called the main vent.

Manifold: A fitting that is used to connect the main to several branches. It is also a point of distribution.

Mapp Gas: A gas that is flammable and colorless. It is made when Methlacetylene-Propadiene is combined with petroleum gas that has been liquefied. This fuel is non-toxic and stable. It is used for soldering and brazing.

MCL: Maximim Contaminant Level. The legal federal limit of contaminant that is allowed in water.

Metal Fatigue: When metal breaks because of contraction, expansion, flexing or bending beyond its maximum limit.

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Nipple: A piece of pipe that is short and installed in the middle of fittings such as couplings.

No-Hub Connector: This connector is used with no-hub iron pipe. It is made from a band of stainless steel attached by hose clamps and a rubber sleeve. There is also another version that is made from two steel bands that are adjustable and a sleeve made from neoprene. It is used for the connection of materials that are not similar. For example, when a drainpipe made from cast-iron is connected to a plastic pipe that is new.

Non-ferrous: Does not contain iron.

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Oakum: Rope made from hemp that is woven loosely. A waterproofing agent such as oil has been used to treat it. Its purpose is the caulking of joints in fittings and a bell and spigot pipe.

Overflow Hood: The hood that covers the overflow on a bath drain.

Overflow Tube: A tube that is vertical located inside the tank of a toilet that guides the flow of water into the bowl in the event that there is a malfunction of the ballcock. It prevents any damage that might be caused by the water if the tank was to overflow. A person is alerted to a possible overflow by the water constantly running. The majority of toilets have a refill tube flowing into the overflow tube. This guides water from the ballcock into the overflow tube and into the toilet bowl, following a siphon break.

O-Ring: A washer made of rubber that has a round shape. It is used to create a seal that is watertight in valve stems.

OD: Outside Diameter. Measurement for a pipe's outside width.

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PB: Polybutylene. Plastic tubing that is able to be bent. Normally used to guide water to fixtures in a bathroom.

PE: Polyethylene. A supply line made from plastic that is flexible.

PEX: Cross-linked Polyethylene. A supply line that is made of plastic that is flexible and has superior strength when compared to PE. It is often used for lines that supply water to bathrooms.

Pitch: When a drain pipe is angled in a downward direction towards the flow of water.

Plumber's Putty: A putty that is used to seal the joints that are in the middle of metal pieces and fixture surfaces.

Plumbing Snake: A piece of metal that is wound like a spiral. It is flexible and thin. The snake is put into a clogged drain and spun around until the debris that is clogging the pipes has been removed.

Plunger: Often called a plumber's helper. A suction cup made of rubber that has a handle often made from wood. It is used to remove clogs in drains.

Pop-Up Drain: For tubs, it is sometimes called a trip lever drain. A drain assembly that is remote control.

Potable: Water that is safe to drink without fear of contamination.

Power Flush System: A system for flushing a toilet that uses compressed water as a method of providing a flush that is pressurized instead of a traditional gravity flush. Toilets that contain a power flush system are normally found in commercial or business environments.

Pressure Balance Valve: A valve for the shower that is used to monitor pressure fluctuations for the purpose of maintaining a balance between water that is cold and hot so there is a constant temperature.

Pressure Head: Plumbing system pressure. This unit of measure is equal to a force that is vertically exerted by water at a one foot depth.

PRV: Pressure Reducing Valve. A valve that is installed on a residential home's main water line. It constricts water that enters the body of the valve. It is used to lower the pressure of water entering a home. The water company uses a very high pressure. This valve lowers the pressure so the water can easily be used in a house without any damage being done to the fixtures.

PVC: Polyvinyl-Chloride. A pipe made of plastic that is rigid. It is typically used for vent, waste and bathroom drain pipes.

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Rated Storage Volume: The amount of water being held in a tank.

Reducer: A fitting that enables different sized pipes to be attached together.

Relief Valve: A valve that can be opened if a system needs excess pressure and/or temperature removed.

Return: A fitting with a bend that is 180 degrees.

Rim Holes: A series of tiny holes on the bottom of a toilet's rim around the entire perimeter of the bowl. When the toilet is flushed, water flows out of these holes and cleans the bowl's inner surface.

Riser: A pipe used for a supply line that rises between stories. It is also a pipe that is vertical and short that guides water to a fixture from a branch.

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Saddle Valve: A valve that is connected to a pipe using a clamping device. It can also be a fitting that enters through the side of a pipe. It is used to quickly connect an existing line to supply water to a device with low water demand.

Scald Guard: A valve that is made to stop drastic changes in the temperature of water through the technology of pressure balance. When cold or hot water pressure goes down, a scald guard valve starts to move back and forth behind the handle of the shower. This is a way of compensating with the drastic change. The temperature of the water is maintained at a constant lever because of this valve. This allows people to shower with the peace of mind that they will not get burned.

Scale: A layer or coating that is thin. This is typically found on interior parts that are preventing the transfer of heat or calcium on the tank's bottom.

Sediment: Sometimes called lime. A substance that settles on a water tank's bottom.

Septic Tank: A tank used for the storage of wastes to enable solids to settle before they are distributed. These tanks are frequently used in rural areas where no sewer line is there to carry the waste to a sewage treatment plant.

Shutoff Valve: Also called a Supply Stop, Straight Stop or an Angle Stop. These valves can be found underneath toilets and sinks. If either of these needs to be repaired or if they malfunction, the shutoff valve can be used to turn off the water.

Siphoning: The effect of pulling or suction that occurs in a toilet's trapway when it becomes filled with waste and water that are outgoing.

Sleeve: A pipe that has been inserted into a wall so that another pipe can be placed through it.

Soft Water: Water that has a mineral content that is low because it has been treated.

Solder: An alloy made of metal that gets melted to fuse a joint between pieces made of metal. It is also the process of having solder melt into the joint.

Soil Pipe: A pipe that is used to transport wastewater from a toilet.

Sweep: A pipe bend that allows waste to pass smoothly in drains.

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T&P Valve: Temperature and pressure valve. This is a valve that is able to be opened to release system temperature and pressure that is in excess.

Tailpiece: The part of a pipe that goes in the middle of a trap and a fixture outlet.

Tee: A fitting that is shaped like the letter T. Three pipe sections can be connected with it.

Tee Fitting: A fitting that enables a pipe to be connected at an angle that is 90 degrees.

Teflon Tape: Tape that is manufactured from fluorocarbon polymer. It contains properties that make it non-stick. A tight seal is created in a joint when Teflon tape is used to wrap around threads of a pipe.

Trap: A part of the drain that is curved. It traps some of the water to stop gases from the sewer from leaking into the bathroom. S traps and P traps are the most common kind of traps that can be found in most bathrooms.

Trap Seal: The water found in a toilet or trap that stops gases from the sewer from coming back up through the drain.

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Valve: A device used for water flow regulation.

Valve Seat: The part of a valve that can not be moved. The flow of water is stopped when the valve seat contacts the part of the valve that can be moved.

Vent: A sloping or vertical part of a drain pipe that enables gasses from a sewer to leave the house and go outdoors. Air is also allowed into the drain system as a way of keeping a balanced air pressure. It also stops the siphoning off of water found in the traps.

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Water Hammer Arrestor: A device that is found close to a fixture. It absorbs the hydraulic shock that often occurs when the supply of a fixture is cut off suddenly. This causes water hammer, a banging noise that is loud in the pipes.

Wet Vent: It connects two or more fixtures. A pipe that vents air into the drains and drains wastewater.

Wax Ring: A seal that can be found in the middle of the toilet and the floor flange to stop fumes and leakage.

Wye Fitting: A fitting for the drain that enables one pipe to be connected to another at an angle of 45 degrees.

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