NCCER Sprinkler Fitter key terms

A procedure in which energy sources such as electricity, steam, or pressurized water are shut off, isolated, and locked with a personal lock so equipment cannot be restarted while workers service it.

An enclosed or partially enclosed area with limited entry and exit that is not designed for continuous occupancy and may contain hazardous air, engulfment hazards, or other dangers requiring a permit.

Gloves, eye protection, hard hat, hearing protection, respirators, and similar wearable gear that shields a worker from jobsite hazards; selected for the task and kept in good condition.

Systems such as guardrails, harnesses, lanyards, and anchor points used to prevent or arrest a drop when working at heights, commonly required at four feet or more.

A hand tool with serrated jaws and an adjustable handle that grips and turns threaded pipe and fittings; the jaw teeth are directional so the tool bites when force is applied.

A machine that cuts tapered threads on steel pipe with a rotating die head while oil cools the cut, producing standard pipe threads that accept threaded fittings.

A cold-forming process that presses a groove into the outside of pipe with rollers so a grooved coupling can grip it, removing less wall material than cut grooving.

A portable ratchet-and-chain device for lifting or pulling loads by hand; its rated capacity must never be exceeded and the load must be kept under control during movement.

A wall-thickness schedule for steel pipe commonly used in sprinkler systems; the schedule number indicates wall thickness, with higher numbers giving thicker walls at the same nominal size.

A mechanical fitting that joins two grooved pipe ends with a gasket and a clamp-style housing bolted around them, allowing some flexibility and faster assembly than threading.

A fitting with an insulating barrier that joins pipes of different metals, such as steel and copper, to stop galvanic corrosion caused by dissimilar metal contact in the presence of water.

A joining method in which filler metal melts above 842 degrees Fahrenheit but below the melting point of the pipe and is drawn into the joint by capillary action to make a strong, leak-tight connection.

A fluid applied to CPVC or PVC pipe and fittings that softens the surfaces so they fuse together; joints need the proper cure time before pressure testing.

A hanger with a U-shaped strap and pin that supports horizontal pipe from a rod attached to the structure, allowing adjustment and slight pipe movement.

A diagonal brace, usually pipe or cable, that connects piping to the building structure to resist lateral or longitudinal movement during an earthquake and keep the system from swinging.

Two rods supporting a horizontal channel or beam from which one or more pipes hang; used where pipes run parallel or where individual hanger attachment points are impractical.

A deliberate U-shaped or offset bend in piping that lets the pipe expand and contract with temperature changes without overstressing joints, hangers, or anchors.

The amount of water, in gallons per minute per square foot, that must be discharged over a specified area to control or extinguish a fire; set by the occupancy hazard.

The hydraulically most demanding area of sprinkler operation used in calculations; it is the section of pipe and sprinklers that requires the greatest pressure to supply the design density.

An equation used in hydraulic calculations to estimate friction loss for water flowing in pipe, based on flow rate, inside diameter, length, and a roughness coefficient.

The pressure remaining at a gauge while water is flowing; measured with static pressure during a flow test to estimate how much water the supply can deliver.

A test that measures static and residual pressure at one hydrant while water flows from another, used to estimate the available water supply for sprinkler system design.

A number expressing the discharge coefficient of a sprinkler or nozzle; flow equals the K-factor times the square root of pressure, so a larger K yields more flow at the same pressure.

A sprinkler with a fast-acting heat-responsive element and low thermal mass that operates sooner than standard sprinklers, often used to reduce the required water demand.

A heat-sensitive solder element that melts at a rated temperature to release a sprinkler's cap and let water flow; its temperature rating is stamped on the deflector.

A valve that holds air pressure on the system side and water on the supply side, opening when a sprinkler releases air so water can enter the dry piping.

A system with closed sprinklers and normally dry piping that fills with water only after detection confirms fire, protecting areas where accidental discharge would be costly.

A valve that opens on a signal from a detection device to admit water to open sprinklers or nozzles at once, flooding an entire hazard area in a single action.

A fixed vertical piping system with hose valves at various levels that lets occupants or firefighters attach hoses to reach a fire on upper floors.

An exterior fitting with siamese inlets where the fire department pumps water into the standpipe or sprinkler system to supplement the building's own supply.

Underground or exterior piping on private property that carries water from the supply source to the sprinkler, standpipe, and hydrant systems it serves.

A pump, usually centrifugal, that boosts water pressure and flow from a supply to meet sprinkler and standpipe demand when the normal water supply is insufficient.

The condition of a fire pump running at zero flow with its discharge valve closed, used to establish shutoff pressure; pumps are rated for a maximum churn pressure.

A small pump that maintains pressure in a fire protection system and makes up minor leaks so the main fire pump does not start for small pressure drops.

The official or agency, such as a fire marshal or building official, with authority to review plans, conduct inspections, and enforce the fire code for a project.

A detailed working drawing prepared by the contractor showing pipe routes, sizes, hanger locations, and equipment, submitted to the designer and AHJ for review before installation.

A pressure test that fills the piping with water, removes trapped air, and holds it above working pressure for a set time to reveal leaks before the system is placed in service.

A test that opens the main drain and records static and flowing pressure to verify the water supply and check for obstructions or closed valves in the supply piping.

A valve at the end of a test line that simulates one sprinkler operating, used to check water flow alarms, flow switches, and the time delay on the alarm.