CA Fire Sprinkler key terms

The total pressure and flow a sprinkler system needs at its supply point, found by adding the pressure required at the farthest sprinkler to friction loss, elevation change, and any device losses.

The hydraulically most demanding set of operating sprinklers for a given design, chosen because it requires the greatest water pressure to supply. Its size depends on density, hazard, and sprinkler spacing.

The minimum water flow rate, in gallons per minute per square foot, that must be delivered over the design area. It is selected from the occupancy hazard classification tables in NFPA 13.

The extra water pressure or flow kept in reserve above the calculated system demand so that actual supply conditions, such as a lower-than-expected residual pressure, still satisfy the design.

The pressure remaining in a water supply main while water is flowing at a measured rate. It is read at a hydrant during a flow test and combined with static pressure to estimate available supply.

The pressure measured in a water supply main when no water is flowing. It reflects elevation and system pressure, and is compared with flowing pressure to judge how much supply the system can deliver.

A field procedure that measures static pressure and residual pressure at two or more flowing rates, usually using hydrants, to determine the available water supply for sprinkler system design.

A pump, typically centrifugal, that boosts water pressure when the public or private supply cannot meet sprinkler demand. It is rated for a specific flow, pressure, and speed and is tested annually.

The pressure a fire pump produces at rated speed with zero flow. It is typically limited to about 140 percent of rated pressure and must be considered so system components are not overpressurized.

A fixed piping arrangement with hose connections that lets building occupants or firefighters attach hoses to reach fires on upper floors or in large buildings. It may be wet, dry, or manual.

An exterior connection where the fire department can pump water into a sprinkler or standpipe system to supplement the building's supply. It must be accessible and clearly marked.

The maximum permitted distance between supports for sprinkler pipe, set by pipe material, size, and standard. It prevents sagging and ensures the pipe stays in place during fire conditions.

A system of braces, cables, and restraints that keeps sprinkler piping from swinging or separating during an earthquake. It includes lateral and longitudinal bracing sized for the seismic design category.

Lateral or longitudinal restraints that resist horizontal movement of sprinkler piping, especially during earthquakes. They transfer pipe loads to the building structure at defined intervals.

A fitting that joins pipe sections while allowing limited movement, often used where sprinkler piping crosses building expansion joints or where seismic separation is required.

The formal check of submitted sprinkler drawings and calculations against adopted codes and standards before installation. Reviewers verify density, spacing, hydraulics, and component compliance.

Detailed shop drawings showing pipe layout, sprinkler locations, hanger details, and hydraulic calculations. They are submitted for approval and used by installers and inspectors during construction.

A category that groups buildings by fire risk, such as light, ordinary, or extra hazard. The classification sets the design density, sprinkler spacing, and water supply requirements.

The final field test before a system is placed in service, including hydrostatic pressure testing, flow tests, and alarm checks, to confirm the installation meets the approved design and code.

A pressure test in which the piping is filled with water and held at a specified pressure, usually above normal working pressure, for a set period to reveal leaks or weak joints.

A test that opens the main drain to measure static and residual pressure at the riser. It confirms that the water supply and control valves are unobstructed and functioning.

A condition in which a sprinkler system or part of it is out of service, whether planned or accidental. The impairment coordinator must notify the fire department and follow a defined procedure.

The specific license category, such as C-16 for fire protection, that authorizes a contractor to bid and perform certain work in California. Bidding outside the classification is illegal.

A surety instrument submitted with a bid that guarantees the bidder will enter the contract if awarded. It protects the owner if the low bidder refuses to sign.

A surety bond that guarantees the contractor will complete the work according to the contract. The owner can claim against it if the contractor defaults.

A percentage of each progress payment withheld by the owner until the project is substantially complete. It provides leverage to ensure the contractor finishes and corrects any defects.

A written agreement that modifies the contract scope, price, or schedule after work begins. It must be documented and approved before the extra work is performed.

A list of incomplete or defective items identified near project completion that the contractor must correct before final acceptance and final payment.

A safety procedure that isolates energy sources, such as electrical or water supply, and attaches tags so equipment cannot be started while workers service it.

Systems and practices, including guardrails, harnesses, and anchors, that prevent workers from falling from heights. It is required above set elevations under safety regulations.

Uncoated carbon steel pipe commonly used for sprinkler systems where corrosion is not a concern. It is joined by threaded fittings, grooved couplings, or welding.

Steel pipe coated with zinc to resist corrosion, used in areas where moisture or certain water conditions would attack bare steel. Cut ends and threads need protection to remain corrosion resistant.

A mechanical fitting that joins pipe ends by gripping grooves rolled or cut into the pipe. It allows faster assembly and some flexibility compared with threaded connections.

A number expressing the discharge characteristics of a sprinkler head, linking flow to pressure. A higher K-factor delivers more water at the same pressure.

A sprinkler with a fast-acting heat-responsive element that operates sooner than standard sprinklers. It is often used to improve life safety in light hazard occupancies.

A valve that holds air pressure on the system side and water on the supply side. When a sprinkler opens, air escapes, pressure drops, and the valve trips to admit water.

A dry sprinkler system that requires a separate detection signal, such as smoke or heat detection, before water fills the piping. It reduces accidental water discharge in sensitive spaces.