Basics of Fire Sprinkler Design

K.S. “Buck” Collier

NICET Level III Fire Protection Engineering Technology/Water Based Systems Layout.

Have worked in industry 28 years. January 1986 to December 1999 employed by Commonwealth Sprinkler Company

February 2000 to present employed by K & E Fire Sprinkler

K.S. Collier

Water SupplyOccupancyBuilding Construction

Elements with Largest Impact on Sprinkler Design

Basic Definition- The water that is available to the building/job site. The design of the sprinkler system is based on this available water

Varies from project to project Can be public or private Public- Locality provides water flow data

◦ Some perform hydrant flow test◦ Some provide calculated information

Private- designs will include tank and pump

Water Supply

The three elements of the water supply are:

Static PressureResidual PressureWater Flow

Water Supply

Static Pressure: The pressure available with no water flow

Residual Pressure: The pressure available with a water flow Flow: The amount of gallons per minute of the water flow

These three make up the Water Supply Curve

Water Supply

Water Supply Curve

Occupancy Determines Hazard Classification Light Hazard (Schools, Office Buildings, Restaurant Seating Areas,

Hospitals)

Ordinary Hazard Group I (Parking deck, restaurant service area, beverage

manufacturing) Group 2 (Repair garages, mercantile, barns, chemical

plants, piers, wood shop)

Extra HazardGroup 1 (Aircraft hangers, printing, saw mills,) Group 2 (Flammable liquid spraying, Manufactured home

assemblies, plastic processing)

Occupancy

The Fire Hazards are based on fuel load

Each Fire Hazard has its own design criteria

Design Criteria are the requirements to which the sprinkler system design is based

Occupancy

Water Density Coverage per Sprinkler Spacing per Sprinkler Remote Area

Design Criteria

Water Density= Gallons per minute (GPM) per sq. ft. covered by the sprinkler

Light hazard= .10 gpm per sq. ft.Ordinary hazard

Group 1= .15 gpm per sq. ft.Group 2 =.20 gpm per sq. ft.

Extra HazardGroup 1 = .30 gpm per sq. ft.Group 2 = .40 gpm per sq. ft

Design Criteria

Coverage per Sprinkler (max. square footage)

Light hazard= 225 sq. ft.

Ordinary hazard= 130 sq. ft.

Extra Hazard= 100 sq. ft.

Design Criteria

Spacing for a Standard Sprinkler (max.)

Light hazard= 15’-0”

Ordinary hazard= 15’-0”

Extra Hazard= 12’-0”

Design Criteria

Remote Area- The area that must be proven, by hydraulic calculations, that if all sprinklers activate, the piping and supply can provide the required pressure and gpm

Light Hazard- minimum of 1500 sq. ft

Ordinary Hazard- minimum of 1500 sq. ft

Extra Hazard- minimum of 2500 sq. ft.

Design Critera

Hazard Comparisons

Construction of Building Effects Design of Sprinkler System◦ Sloped Ceilings

Impact reaction time of sprinklers thus requiring an increase in remote area size by 30%.

1500 sq ft. +30% (450 sq. ft.) = 1950 sq. ft.◦ Unconditioned Spaces

Dry System required for unconditioned spaces Dry Systems impact reaction time of sprinklers thus

requiring and increase in remote area size by 30%. 1500 sq ft. +30% (450 sq. ft.) = 1950 sq. ft.

Building Construction

Example: seasonal restaurant seating area◦ Heated flat ceiling

1500 sq ft remote area◦ Unheated flat ceiling

1500 sq ft. +30% (450 sq. ft.) = 1950 sq. ft. remote area

◦ Unheated sloped ceiling 1500 sq ft. +30% (450 sq. ft.) = 1950 sq. ft. +30%

(585 sq. ft.) = 2535 sq. ft. remote area

Building Construction

Thank you for allowing me to give this brief presentation on Basics of Fire Sprinkler

Design

Sincerely,K.S. “Buck” Collier

February 5, 2014

ASCET Central Virginia Chapter