KY Fire Sprinkler cheat sheet

Light hazard design density starts at 0.10 gpm/ft² over 1,500 ft²; Ordinary Group 1 at 0.15 gpm/ft² over 1,500 ft²; Ordinary Group 2 at 0.20 gpm/ft² over 1,500 ft² (NFPA 13 density/area curves).

Maximum protection area per sprinkler: 225 ft² for light hazard, 130 ft² for ordinary hazard pipe schedule systems; hydraulic designs follow the density/area curves and spacing rules of Chapter 8-19.

Standard spray upright/pendent spacing: max 15 ft between sprinklers and max 15 ft from wall on noncombustible unobstructed construction (light hazard); reduce to 12 ft where required by construction type.

Minimum clearance: 1 in. (25 mm) below deflector to ceiling for standard spray sprinklers; 18 in. (457 mm) below noncombustible ceiling for storage sprinklers unless listed otherwise.

Sprinkler temperature rating: ordinary 135-170°F, intermediate 175-225°F, high 250-300°F, ultra-high 325-650°F. Choose rating at least 25°F above max ambient ceiling temperature.

Quick-response sprinklers may use the design area reduction (30% reduction, min 1,500 ft²) only where allowed by NFPA 13 and with wet systems, light/ordinary hazard, and no sloped combustible ceilings.

Branch line and cross main sizing: pipe schedule tables (light hazard 1 in. to 2 sprinklers, 1¼ in. to 3, 1½ in. to 5, 2 in. to 10, 2½ in. to 30, 3 in. to 60, 3½ in. to 100, 4 in. and larger 100+).

Hanger spacing: 12 ft max for 1 in. and smaller pipe, 15 ft max for 1¼ in. and larger; one hanger within 3 ft of the end of the pipe and within 6 ft of a change in direction (NFPA 13 Ch. 17).

NFPA 13R applies to residential occupancies up to and including four stories above grade plane; buildings taller than four stories require NFPA 13.

NFPA 13D applies to one- and two-family dwellings and manufactured homes; it is not a life-safety code and does not require a fire department connection or water flow alarm.

13D design: one sprinkler at 13 gpm minimum for 1-2 sprinkler systems; two sprinklers at 13 gpm each for larger; total flow not required to exceed 26 gpm for one- and two-family dwellings.

13D water supply must supply the system demand for at least 10 minutes (7 minutes if the system has a tank with automatic refill or is connected to a municipal supply).

13R design density: 0.05 gpm/ft² over the entire floor area of the most remote room, or 0.10 gpm/ft² over the four most remote sprinklers, whichever is greater; minimum 13 gpm per sprinkler.

13R sprinkler spacing max 12 ft between sprinklers and 6 ft from walls; max coverage 144 ft² per sprinkler (may be increased to 196 ft² where listed).

13R/13D systems do not require sprinklers in bathrooms under 55 ft², closets under 24 ft², attics, garages, or concealed spaces of certain construction if the exceptions in the standard are met.

13R systems require a single control valve with waterflow switch; 13D systems need a shutoff valve and may omit the waterflow alarm where permitted.

Class I standpipe: 2½ in. hose valve for fire department use; Class II: 1½ in. hose valve with hose for occupant use; Class III: both 1½ in. and 2½ in. valves.

Minimum residual pressure at the topmost outlet: 100 psi for Class I and Class III; 65 psi for Class II; 100 psi for combined systems where the standpipe demand is the greater.

Standpipe flow: 500 gpm for the hydraulically most remote standpipe plus 250 gpm for each additional standpipe, with a max of 1,250 gpm total in a building.

Maximum horizontal and vertical travel to a hose valve: 130 ft of hose plus 30 ft of stream; hose valves spaced so all portions of the floor are within the reach.

Dry standpipes must be capable of being drained; automatic dry pipe valves or manual valves with a fire department connection are permitted; air pressure maintained to prevent tripping.

Fire department connection: 100 psi at the FDC at the standpipe system demand; FDC must be located within 100 ft of a public hydrant and accessible to the fire department.

Standpipe pipe sizing by schedule: 2½ in. for 1-2 risers, 4 in. for 3 or more risers in a combined system; hydraulic design is permitted as an alternative.

Hose valves must be 3-6 ft above the floor, accessible, and protected in cabinets when required; valves must have caps and chains.

Fire pump rated flow: pump must be selected so the rated point is at or below 150% of rated flow on the curve; the pump must produce at least 65% of rated pressure at 150% of rated flow.

Pump must be capable of delivering at least 95% of rated pressure at zero flow (shutoff) without exceeding 140% of rated pressure; churn pressure is limited to 140% of rated.

Net positive suction head (NPSH) required must be less than NPSH available at all flows; NPSH margin is typically 10% or per NFPA 20.

Fire pump driver sizing: electric motor sized so it does not overload at any point on the pump curve; diesel driver rated for the pump's maximum brake horsepower.

Automatic transfer switch, controller, and power supply must be dedicated and arranged for automatic starting; weekly churn test for electric pumps is required by NFPA 25.

Fire pump testing (NFPA 25): weekly no-flow (churn) test for electric pumps; annual flow test at 100%, 150%, and peak; monthly inspection of diesel fuel and battery condition.

Fire pump must be located in a fire-rated room with 2-hour separation or protected by sprinklers where the building code requires; suction piping must be as short and direct as possible.

Jockey pump: maintains system pressure and is set to start before the fire pump; typically set at 10 psi above fire pump start and stops at the fire pump start pressure.

Private fire service main minimum size is 4 in. for hydrant supply mains; 6 in. minimum where the main serves a fire department connection or where required by the authority having jurisdiction.

Underground piping must be buried below the frost line; typical minimum cover is 30 in. to the top of pipe unless local frost depth dictates deeper (Kentucky varies by region).

Thrust blocks or restrained joints are required at all changes in direction, tees, dead ends, and hydrant branches; thrust block size depends on soil bearing and test pressure.

Hydrostatic test: 200 psi for 2 hours or 50 psi above working pressure, whichever is greater; test before backfilling where possible and with exposed joints.

Flushing: minimum 10 ft/s flow velocity through the main before testing; flushing must continue until water runs clear.

Hydrant spacing: typically 300 ft to 500 ft as required by the local code; hydrants must be located within 50 ft of the fire department connection and accessible.

Gate valves on private mains: valve must be installed on each branch and at intervals not exceeding 800 ft in a looped system; indicator posts required for buried valves.

Tapping and connection to public main must follow the water purveyor's requirements; backflow prevention and metering may be required by the local utility.

Weekly: inspection of gauges (wet, dry, preaction), waterflow alarm devices, and fire pump churn test for electric pumps.

Monthly: inspection of alarm valves, dry pipe valves, deluge valves, and fire pump system including diesel fuel level, battery condition, and controller indicators.

Quarterly: waterflow alarm test, valve status check, and hydrant inspection; annual: main drain test, flow test of hydrants, and fire pump flow test at 100%, 150%, and peak.

Main drain test: static pressure reading, then open drain fully and record residual pressure; a drop of more than 10% from the previous test indicates a problem in the supply.

Five-year: internal inspection of sprinkler piping and gauges, and full flow test of standpipes; sprinkler gauge replacement every 5 years for dry systems.

Sprinkler replacement: fast-response sprinklers at 20 years, then every 10 years; standard-response at 50 years, then every 10 years; replace any sprinkler showing corrosion, paint, or damage.

Dry pipe valve trip test: annually with the main drain open; record the time to trip and the air pressure; compare with the previous year's results.

Records must be maintained and made available to the AHJ; NFPA 25 requires retention of inspection and test records for at least one year or as required by the AHJ.

Hazen-Williams formula: p = 4.52 Q^1.85 / (C^1.85 d^4.87), where p is friction loss in psi/ft, Q is flow in gpm, d is inside diameter in inches, and C is the roughness coefficient (120 for steel, 150 for copper/PVC).

C-factor values: black steel 120, galvanized 120, cement-lined 140, copper 150, PVC/CPVC 150; use the correct value for the pipe material in the calculation.

Design area: the hydraulically most demanding area of operation; reduce the design area by 30% for quick-response sprinklers (min 1,500 ft²) where permitted by NFPA 13.

Density/area curves: the required density is selected from the curve based on hazard classification; the area may be increased or decreased based on the curve's slope.

Balancing: the flow at each branch line must be balanced so that the pressure at each node is consistent; use the loop or node method to solve the network.

Velocity limit: keep water velocity in the sprinkler system at or below 20 ft/s for steel pipe to limit erosion and noise; 15 ft/s is often used for design.

Safety margin: add 10-15 psi to the calculated demand to account for uncertainties and to ensure the supply meets the demand; compare the supply curve to the demand curve.

Pipe sizing by schedule: light hazard branch lines 1 in. for 2 sprinklers, 1¼ in. for 3, 1½ in. for 5, 2 in. for 10, 2½ in. for 30, 3 in. for 60, 3½ in. for 100, 4 in. and larger for 100+.

Plan submittal must include: hydraulic calculations, sprinkler layout, pipe sizes, hanger locations, water supply curve, and the contractor's license and permit application.

Working plans must be drawn to scale and show the entire system including risers, cross mains, branch lines, and the location of all sprinklers and valves.

Hydraulic calculations must be submitted with the plans and must show the design area, density, and the supply curve; calculations must be signed by a licensed engineer or designer.

Permit required before installation, alteration, or repair of a sprinkler system; the AHJ reviews plans and issues the permit; inspections occur at rough-in, final, and hydrostatic test.

Shop drawings must be approved by the AHJ before installation; the contractor must keep approved plans on site during construction.

As-built drawings must be submitted at completion; they must reflect the actual installed system and any field changes.

Kentucky requires a licensed sprinkler contractor and certified installer; the license number must appear on the permit application and plans.

Submittal review checklist: water supply adequacy, hazard classification, sprinkler spacing, hydraulic calculations, and compliance with NFPA 13 and the Kentucky Building Code.

Kentucky Fire Prevention Code (KFP) is based on the International Fire Code (IFC) and is enforced by the State Fire Marshal; local jurisdictions may adopt amendments.

Kentucky Building Code is based on the International Building Code (IBC); sprinkler requirements follow the IBC and NFPA 13 for the occupancy classification.

Sprinkler contractor licensing: Kentucky requires a license from the Department of Housing, Buildings and Construction; a certified installer must be employed by the licensed contractor.

Permits: application to the local AHJ or the State Fire Marshal, with plans and fees; the AHJ issues the permit and conducts inspections.

Fire alarm and sprinkler plans must be reviewed by the AHJ; the contractor must notify the AHJ before covering any piping and before the final inspection.

Kentucky requires a Certificate of Occupancy after final inspection; the AHJ may require a fire flow test and a water supply analysis before approval.

Violations of the fire code may result in fines, stop-work orders, or revocation of the contractor's license; the State Fire Marshal has enforcement authority.

Continuing education: licensed sprinkler contractors and installers must complete continuing education as required by the Department of Housing, Buildings and Construction.

Personal protective equipment: hard hat, safety glasses, high-visibility vest, steel-toe boots, and gloves are required on all construction sites; fall protection above 6 ft.

Pipe handling: use proper lifting techniques; two-person lifts for pipe over 10 ft; do not roll pipe off a truck without a spotter.

Lockout/tagout: before working on a system connected to a water supply, isolate and lock the control valve; verify zero pressure before opening the system.

Hot work: a hot work permit is required for welding, cutting, or grinding; a fire watch must be maintained for 30 minutes after hot work is complete.

Material storage: pipe must be stored on dunnage and kept dry; CPVC must be protected from sunlight and stored away from heat sources.

Coordination: sprinkler piping must be coordinated with structural, mechanical, and electrical trades; use BIM or coordination drawings to avoid clashes.

Testing safety: hydrostatic testing requires the area to be clear of personnel; use a test cap and gauge; do not stand in front of a test cap during pressurization.

Excavation safety: trench protective systems required for trenches 5 ft or deeper; keep spoil piles at least 2 ft from the edge of the trench.