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SAE – Society of Automotive Engineers standard; a thread size used on nuts and bolts but not pipe connections.

SJ – Slip Joint

SMLS – Seamless pipe

SN – Satin Nickel finish

SS – Stainless Steel

STD – Standard

SV – Service Victory. A designation for service weight cast iron drainage pipe.

Saddle Tee – Fitting that taps into the side of a pipe, used to make quick connection to an existing line.

Saddle Valve – A valve mounted on a pipe run by a clamping device, or saddle tee to provide a water supply for a low-demand device.

Safe Drinking Water Act – An amendment to the Public Health Service Act, which was passed in 1976 to protect public health by establishing uniform drinking water standards for the nation. In 1986 SDWA Amendments were passed that mandated the EPA establish standards for 83 drinking water contaminants by 1992 and identify an additional 25 contaminants for regulation every 3 years thereafter.

Safety Shutoff Valve – A device on a gas appliance that shuts off the gas supply to prevent a hazardous situation. A flame safety shutoff operates when the actuating flame becomes extinguished.

Sag Pipe – A section of a sewer line that is placed deeper in the ground than normal in order to pass under utility piping, waterways, rail lines, highways, or other obstacles. The sewer line is raised again after passing under the obstacle.

Sanitary Fitting – Fitting that joins the assorted pipes in a drain, waste, and vent system, designed to allow solid material to pass through without clogging.

Saponification – The process in which a fatty acid is neutralized with an alkali or base to form a soap.

Sanitary Sewer – House drain that carries wastewater away from the house to a sewer system or septic tank.

Scale – A thin coating or layer, usually calcium on the bottom of a tank or interior parts that may prevent heat transfer.

Schedule – Numbers assigned to different wall thickness of pipe (e. g. sch 40).

Scupper Drain – Also known as Soil Pipe, No Hub pipe is used in certain locales and for commercial buildings for soil stacks. It cannot be soldered, threaded, or welded, and can only by connected by steel banded rubber sleeved adapters.

Seal-Off Fitting – Fitting which prevents gas leakage from moving from one section of pipe to another.

Sealed Combustion – Sealing of combustion chamber to prevent spillage of combustion products.

Sealed Combustion Heater – A heater which pulls combustion air from outside the structure and vents combustion by-products to the outside.

Seamless Pipe – Pipe with no weld in the circumference.

Secondary Air – The remaining air needed for complete combustion besides primary air. This is the air surrounding the flames outside the burner ports.

Sediment – The substance that settles on the bottom of a water tank. Also known as lime.

Self-Rimming Sink – Sink with no metal ring that has a built-in lip of the same material which supports it in the vanity top.

Series System – System where a primary heater preheats water to a given desired general purpose temperature and feeds into another heater.

Serial/ Model/ Rating Plate – A permanent information plate attached to major home appliances. The plate includes product model and serial numbers, plus information about wattage or BTU requirements.

Service Entrance – Pipe connecting the water company piping to the water meter.

Service Pressure – The range of pressure in the pressure tank during the pumping cycle, usually expressed in pounds per square inch gauge. (P. S. I. G. )

Service Sink – Deep fixed basin, supplied with hot and cold water, which is used for rinsing of mops, disposal of cleaning water, or washing clothes and other household items.

Service Tee – Tee fitting with male threads on one run opening and female threads on the other two.

Sewer Gas – Gases, esp. methane, which may be combustible and poisonous from the decay of organic materials in the sewer system.

Shallow Well – A well with a pumping head of 25 feet or less, permitting use of a suction pump.

Shroud – Color-matched component under a wall-mount lavatory that covers the drain outlet for aesthetic purposes.

Shower Receptor – A one-piece base (floor) unit used as a shower, for example, to catch water and direct it to a center drain.

Shutoff Valve – Usually refers to angle stops installed under sinks and toilets, but also valves installed on branch lines and alongside the meter.

Side Cutter – A heavy duty auger tip for large diameter pipes.

Sight Hole – Generally a window on oil-fired products that allows the viewing of burner and flame patterns.

Simplex Basin – An ejector pump container usually 18″ x 30″ for single family homes. Single Threshold Type of shower base used in a three wall installation with the threshold being the side with the door.

Siphon – A pipe connecting two canals. A tube or pipe through which water flows over a high point by gravity.

Siphon Break – The point in a toilet flush cycle when air is re-introduced into the trapway, breaking the siphonic action. This is characterized by the deep gurgling sound heard at the end of a flush.

Siphon-Jet Water Closet – A toilet having a siphonic trapway at the rear of the bowl and an integral flushing rim and jet.

Siphon-Vortex Water Closet – A toilet having a trapway at the rear of the bowl integral flushing rim and a water supply system with or without a jet, which does not feed directly into the trap.

Siphon Wash Closet – A toilet having a trapway at the rear of the bowl and integral flushing rim, and minimum dimensions of 5″ x 4″ water spot and 1 �” ball pass.

Siphoning – The suction or pulling effect that takes place in the trapway of a toilet as it is filled with outgoing water and waste.

Sisson Joint – This is a joint between pipes that is larger on one end than the other. NOTE: Sisson joints are often prohibited for drainage system purposes.

Sleeve – Pipe which is passed through a wall for the purpose of inserting another pipe through it.

Slide Bar – Type of shower component designed for the attachment of a hand-shower. The mounting bracket can be adjusted at different heights to accommodate individual preference.

Sliding Inner Door – A door that slides along the combustion chamber radius for easy access to the burner and pilot.

Sliding Panels – The moving panels in a bypass door. (as in shower doors)

Slip Gasket – Elastomer (natural occurring elastic substance) gasket, usable with a hub and spigot pipe because it has a tapered cross section.

Slip Joint – Same as IPS. (Female) 1/2″ IPS Faucet, 7/8″ IPS Toilet. Internal Pipe Swivel Connection. A connection made with compression fittings.

Soft Flame – A flame partially deprived of primary air such that the combustion zone is extended and the inner cone of the flame is ill-defined.

Soft Water – Water that has a low calcium and magnesium content.

Soil Cutter – A device used to cut No Hub pipe, consisting of a handle and a cutting chain, similar to a chain wrench in appearance.

Soil Pipe – A sewer pipe for carrying off waste from toilets.

Soil Stack – Largest vertical drain line to which all branch waste lines connect. This line carries waste to the sewer line.

Solder – A metal alloy that is melted to create a fused joint between metal pieces. Also the act of melting solder into the joint.

Solenoid – A coil of wire in the form of a cylinder that, when carrying a current, resembles a bar magnet.

Solvent Weld – Any of the types of PVC pipe and fittings that are fastened together with solvent-based cement.

Soot – A black substance, mostly consisting of small particles of carbon, which can result from incomplete combustion and appear as smoke.

Spark Ignition – Intermittent ignition devices that utilizes a spark to light a flame.

Spark Test – A test procedure to evaluate the integrity of the glass lining.

Specific Gravity – The ratio of the weight of a specific volume of a substance compared to the weight of the same volume of pure water at 47 degrees C.

Specific Heat – Amount of heat required to raise the temperature of a kilogram of a substance one degree Celsius.

Spigot – The plain end of a cast-iron pipe. The spigot is inserted into the bell end of the next pipe to make a water tight joint.

Spigot Soil Adapter – Hub adapter to connect PVC with soil pipe.

Spline Adapter – Device sometimes required to form a mating connection between the splines of a valve stem and the splines inside a faucet handle.

Spore – A threaded opening on the water heater tank. Also a tool for digging having characteristics of a shade and chisel.

Spud – A threaded opening on the water heater tank. Also a tool for digging having characteristics of a shade and chisel.

Stack – The vertical main in the drain, waste, and vent system, extending one or more stories.

Stacking – The ability of hot water to form layers of different temperatures in the tank stratification.

Stainless Steel Sink – Steel sinks made of solid stainless material, durable, and immune to rust and corrosion. The gauge measures the thickness of the steel, with a lower number indicating thicker steel. Their underside is often sprayed with a rubberized undercoating to provide a sound-deadening barrier, eliminate condensation, and reduce heat transfer.

Stand Pipe – Open vertical pipe that receives water from a washing machine. Also the vertical pipe run supplying water to a fire sprinkler system; also large vertical pipe into which water is pumped in order to produce a desired pressure; a high vertical pipe or reservoir that is used to secure a uniform pressure in a water-supply system.

Static Discharge Head – The vertical distance from the pump to the highest outlet in the water system Stand By Loss. The amount of heat lost while a unit is in stand by mode.

Static Lift – The vertical distance between source and discharge water levels in a pump installation.

Static Pressure – The pressure when no water is flowing.

Static Water Level – The undisturbed level of water in the well before pumping.

Stem – Part of the faucet that holds the handle on one end and the washer on the other. Stiffener A galvanized bushing used to strengthen tubing to fit in a leadpak coupling.

Stem Assembly – Moving part of the valve that controls the amount and temperature of water released.

Stillson Wrench – Pipe wrench

Stop / Stop Valve – The shutoff valve under sinks and toilets. Allows water supply to be cut off to one fixture without affecting the water supply to other fixtures.

Stop and Drain Fitting – Plug-type valve used to tap into a water main to control the flow to a branch line, which has a side opening to shut off the water and allow it to drain out so the pipe won’t freeze.

Storage Tank – A tank used to hold a specific volume of water.

Storm Drain – Drain used to receive and convey rain water, surface water, and ground water away from buildings.

Straight Cross – Fitting that connects four pipes of the same diameter.

Straight Pipe Threads – A special kind of straight thread used only on iron pipe, toilet, and faucet fittings. A cone seal or gasket is usually included because straight threads will not form a complete seal without a gasket of some kind.

Straight Stop – An emergency stop valve that is usually installed before the water supply line to toilets and faucets. Similar to angle stops but the line does not change direction.

Strainer Pot – A housing on the influent side of a pump that serves as a priming chamber and a receptacle for the strainer basket.

Strap Wrench – Tool with metal body and heavy cloth or metal mesh belt used for turning pipe.

Street Ell – A 90 degree elbow joint with a hub on one end and male threads on the other. Used to make an angled connection between pipe or tubing and a fitting with a hub.

Stub-Out – Short lengths of pipe installed during rough-in to which fixtures and drains will eventually be installed.

Stud Guard – Short band of metal attached to wall studs to prevent nails from penetrating and damaging pipes.

Stuffing Box – That portion of the pump that held the packing and now holds the mechanical seal.

Submergence – The distance the ejector, foot valve or submersible pump is installed below the pumping level.

Suction Head – The head on the suction side of the pump. This is subtracted from the discharge head to determine the head being produced by the pump. It is a sum of the static, pressure and friction heads.

Suction Static Lift – Same as Suction Static head. This term is only used when the pump centerline is above the suction tank fluid surface.

Sump – A pit or pool for draining, collecting, or storing water. A chamber which provides water to the pump.

Supply Kit – Usually a kit of all parts needed to connect a faucet or toilet to the pipes coming out of the wall. Usually includes stop valves, water connectors, and escutcheons.

Supply Stop – The valve controlling water supply to a toilet.

Surface Mount – Typically refers to thermostats mounted on the outside of the tank that senses temperature through the steel tank.

Surface Pump – A mechanism for removing water or wastewater from a sump or wet well.

Suspended Solids – Solid particles in water which are not in solution.

Sweating – Term for soldering. Also formation of condensation on the outside of pipes or toilet tanks.

Sweep – A drain ell fitting with a long radius that allows for smooth passage of waste. Fittings with abrupt changes of direction, such as a vent tee, may only be used for vents.

Swing Joint – A flexible sprinkler connection made by connecting three threaded elbows fittings together.


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Source: “Plumbing Terms” Standard Plumbing Supply. 11 Sept. 2008