OK Fire Sprinkler flashcards
OK Fire Sprinkler · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- NFPA 13
- The primary standard for design and installation of automatic sprinkler systems; it does not govern ongoing inspection, testing, and maintenance.
- NFPA 25
- Standard for inspection, testing, and maintenance of water-based fire protection systems; it sets frequencies and records for valves, gauges, alarms, and drains.
- Authority having jurisdiction
- Authority having jurisdiction; the official or agency that reviews plans, issues permits, conducts inspections, and enforces the adopted fire code.
- Sprinkler discharge formula
- Q equals K times the square root of pressure, where Q is flow in gpm, K is the sprinkler discharge coefficient, and P is pressure in psi.
- Density-area method
- Design density in gpm per square foot multiplied by the remote design area in square feet gives the required sprinkler flow before hose and other demands.
- Hazen-Williams formula
- Estimates friction loss in water-filled pipe using flow, internal diameter, and a C factor; in US units the constant is 4.52 for psi per foot.
- Water supply curve
- A plot of available pressure versus flow at the system connection; the demand point must fall below or on the curve with all adjustments applied.
- Wet-pipe system
- A sprinkler system with water in the piping at all times; it is the simplest and fastest-acting type where freezing is not a concern.
- Dry-pipe system
- Uses compressed air or nitrogen to hold a dry-pipe valve closed; water enters after a sprinkler opens and pressure drops, so design area is increased.
- Deluge system
- Open sprinklers or nozzles discharge together when detection operates a deluge valve; used where rapid application over an area is needed.
- K-factor
- Sprinkler discharge coefficient in gpm per square root psi; a larger K produces more flow at the same pressure and affects required pressure.
- Quick-response sprinkler
- Sprinkler with a fast-responding thermal element; response rating is separate from temperature rating and may affect design area allowances.
- Alarm check valve
- A wet-pipe valve that opens to supply water and directs a portion of flow to an alarm line when a sprinkler operates.
- Grooved coupling
- Mechanical pipe joint using rolled or cut grooves and a gasket housed in a coupling; must be listed for fire protection and installed to the manufacturer's torque.
- Dielectric union
- Fitting that separates dissimilar metals to reduce galvanic corrosion; commonly used where steel meets copper or brass in sprinkler piping.
- Thrust restraint
- Method of resisting unbalanced pressure forces at underground fittings and bends using blocking, restrained joints, or tie rods.
- Sway bracing
- Seismic restraint that limits lateral or longitudinal pipe movement; bracing type, spacing, and attachment depend on the adopted seismic provisions.
- Hanger rod
- Vertical support rod that carries sprinkler pipe from building structure; rods must be sized, attached, and not bent or damaged.
- Seismic separation assembly
- Flexible arrangement at building expansion or seismic joints that allows independent movement without damaging sprinkler piping.
- Fire pump churn
- Pump operating at shutoff or no-flow condition; NFPA 20 limits shutoff pressure to a percentage of rated head and requires relief protection.
- Jockey pump
- Small pump that maintains system pressure and prevents main fire pump from starting on minor leaks; it is not a fire pump substitute.
- Anti-vortex plate
- Device in a water storage tank that prevents air from being drawn into the fire pump suction as the water level drops.
- Approved working plans
- Plans and calculations stamped approved by the authority having jurisdiction; they must be available on site and changes require reapproval.
- Rough-in inspection
- Inspection of concealed sprinkler piping, hangers, and components before ceiling or wall closure; approval is needed before concealment.
- Record of completion
- Document signed by the installing contractor and owner listing system details, tests, and approvals; it is part of the acceptance record.
- Hydrostatic test
- Pressure test of sprinkler piping, commonly 200 psi for two hours or 50 psi above working pressure when higher, with no leaks.
- Main drain test
- Flow test through the main drain that indicates water supply and valve condition; results are compared with previous baseline readings.
- Dry-pipe trip test
- Test that simulates sprinkler operation to verify the dry valve trips and water reaches the test connection within the required time.
- NFPA 25 annual inspection
- Yearly check of gauges, valves, alarm devices, and waterflow alarms; specific components have monthly, quarterly, or five-year frequencies.
- Lockout/tagout
- Procedure that isolates hazardous energy before maintenance; it protects workers from unexpected startup or release of pressure and electricity.
- Hot work permit
- Written authorization for cutting, welding, or soldering; it defines fire watch, combustible clearance, and post-work monitoring.
- Impairment coordinator
- Person responsible for managing a fire protection impairment, notifying affected parties, and arranging fire watch or alternate protection.