OK Fire Sprinkler key terms

The organization, office, or individual with legal authority to enforce the fire code, approve plans, witness tests, and grant interpretations; in Oklahoma this is often the State Fire Marshal or a local fire department.

The installation standard for automatic sprinkler systems, covering hazard classification, design methods, water supply, materials, hangers, acceptance testing, and maintenance; Oklahoma adopts an edition of this standard as the technical basis for sprinkler work.

A state-issued credential required to contract for sprinkler installation, alteration, or testing in Oklahoma; applicants typically qualify through documented experience and examination, and the work still requires local permits and inspections.

The selected water application rate, in gallons per minute per square foot of floor area, that the system must deliver over the design area; it is read from the density/area curves for the occupancy hazard.

A design method pairing a discharge density with a remote area size taken from the occupancy hazard curves, then verifying by hydraulic calculation that the supply can meet the resulting demand.

Grouping of occupancies by fuel load and expected fire severity into light, ordinary (Groups 1 and 2), and extra hazard classes, which set the density, area, and sprinkler requirements used in design.

The portion of the system, usually the hydraulically most demanding, assumed to have all sprinklers flowing at design density; its size depends on hazard, construction, ceiling height, and sprinkler response type.

A pressure-loss analysis that starts at the most remote flowing sprinkler, adds friction and elevation losses through pipe and fittings, and compares total demand with the available water supply.

A roughness coefficient in the Hazen-Williams friction formula; NFPA 13 assigns values such as about 100 for unlined ferrous pipe, 120 for galvanized, and 140 for cement-lined, with lower values producing greater loss.

The pressure reading at a gauge while water is discharging during a flow test; subtracting it from static pressure, together with the measured flow, defines the available water supply curve.

The extra pressure required at the design flow beyond the calculated system demand, covering supply test uncertainty, future demand growth, and minor piping changes; often a modest fixed increment.

Piping kept full of pressurized water so an opened sprinkler discharges immediately; the simplest and most common arrangement, used wherever the building is reliably protected from freezing.

Piping charged with pressurized air or nitrogen that holds a dry pipe valve closed against the water supply; air must vent through an open sprinkler before water arrives, adding delay.

A dry system in which fire detection first opens a valve to fill the piping, and water discharges only when a sprinkler also opens; the double interlock reduces accidental discharge risk.

A system using open sprinklers or nozzles connected to a deluge valve, so detection actuation admits water to all heads in the zone at once, intended for high-hazard or special fire challenges.

Early Suppression Fast Response sprinkler designed to suppress high-challenge storage fires with high-momentum discharge; permitted only within strict limits on ceiling height, storage height, clearance, and commodity.

The largest floor area one sprinkler may protect, set by hazard class, sprinkler type, and ceiling construction; it works together with maximum spacing limits to fix the layout.

A sprinkler's nominal discharge coefficient linking pressure to flow through the relation Q equals K times the square root of pressure; larger K values deliver more water at the same pressure.

A sprinkler intended to control a fire by delivering the density/area design over the assumed remote area, typically a standard spray head; the default choice for most hazard-classified designs.

A sprinkler with a fast thermal element and low response time index, operating earlier than standard-response heads; it can allow reduced design areas where the code permits.

The nominal temperature at which a sprinkler's heat-responsive element operates, identified by color coding; it is selected well above normal ceiling temperatures to avoid premature activation.

The metal plate or frame part that shapes and spreads sprinkler discharge into the intended pattern; its orientation and distance from the ceiling affect coverage and obstruction rules.

A wet-pipe check valve with a trim port that directs water to a hydraulic alarm or pressure switch when flow occurs, while preventing reverse flow into the supply.

A valve holding supply water back from air-pressurized piping, opening when air pressure drops after a sprinkler operates; often a differential clapper design with an intermediate chamber.

A paddle or vane device sensing sustained water movement in the pipe and sending an alarm signal to the fire alarm panel; its delay and placement follow NFPA 72 and NFPA 13.

A valve and orifice at the end of the most remote branch line that simulates one sprinkler flowing, used to confirm waterflow switch operation and alarm delay times during testing.

An exterior siamese connection letting a responding pumper supplement the sprinkler supply; it needs a check valve, clear access, and signage identifying the system it serves.

The vertical supply pipe connecting the underground main to the overhead system, carrying the main control valve, check valve, drain, gauges, and alarm attachments.

The smallest sprinkler pipe, running from the cross main and serving sprinklers directly; its diameter and the number of heads it supplies are limited by code tables or calculations.

A prescriptive way to size piping from tables based on how many sprinklers a pipe serves, allowed only for limited hazards and tree layouts; it does not verify water supply adequacy.

A mechanical joint formed by grooves rolled or cut into pipe ends, joined with a gasket and clamp housing; it permits rapid assembly and slight flexibility and requires listed components.

A support that carries the dead weight of pipe and water at code-specified intervals, using listed rods, clevis hangers, or trapeze assemblies attached to structural members.

Lateral and longitudinal bracing that resists seismic or thrust forces, separate from gravity hangers; required in seismic design categories and coordinated with flexible couplings and clearances.

A listed pump, usually centrifugal, that boosts pressure and flow from a water supply to meet sprinkler demand; it is rated at a specific flow, head, and speed.

Scaled drawings submitted for approval showing piping layout, sizes, sprinkler locations, hangers, and details, accompanied by hydraulic calculations and water supply data before installation begins.

A sign at the riser stating design density, remote area, required flows and pressures, and supply information; it guides inspectors and future alterations to hydraulically calculated systems.

A water pressure test of installed piping at a level above normal working pressure, held for a specified time, to reveal leaks in joints and fittings before acceptance.

The post-installation testing and documentation required before final approval, including hydrostatic, flow, alarm, and supervisory checks, often witnessed by the authority having jurisdiction.

Any condition leaving a system or part of it out of service; it triggers notification, tagging, a documented impairment program, fire watch where required, and prompt restoration.

Written authorization for welding, cutting, or grinding after combustible hazards are removed, with a fire watch, extinguishing equipment, and checks before and after the work.