Kitchen Hood Suppression Calculator

Kitchen fire suppression system sizing from hood dimensions.

Hood length (ft)

Hood width (ft)

Number of deep-fat fryers

Number of grills/griddles

Other cooking appliances

Duct length (ft)

Tab to move between fields

Total nozzles required

Appliance nozzles4

Plenum nozzles1

Duct nozzles1

Wet chemical agent (gal)9

Tank size (gal)6

Number of tanks2

Gas valve shutoffs4

K-class extinguishers needed1

Hood area (sq ft)40

How to Use This Calculator

How the result changes with Hood length (ft)

Hood length (ft): Length of the kitchen exhaust hood in feet.
Hood width (ft): Width (depth) of the kitchen exhaust hood in feet.
Number of deep-fat fryers: Each fryer requires a dedicated suppression nozzle per UL 300 listing.
Number of grills/griddles: Flat grills and griddles each require nozzle coverage.
Other cooking appliances: Ranges, woks, broilers, and other heat-producing appliances.
Duct length (ft): Length of exhaust duct from hood collar to exterior termination.

Total nozzles required: Sum of appliance, plenum, and duct nozzles.
Appliance nozzles: Nozzles aimed at cooking surfaces.
Plenum nozzles: Nozzles protecting the hood plenum area.
Duct nozzles: Nozzles for exhaust duct protection.
Wet chemical agent (gal): Estimated agent quantity at ~1.5 gal per nozzle.
Tank size (gal): Recommended standard tank size.
Number of tanks: Tanks required (multiple if demand exceeds 6-gal single tank).
Gas valve shutoffs: Fuel/electric shutoff actuators required for appliances.
K-class extinguishers needed: Portable K-class extinguishers required within 30 ft travel per NFPA 10.
Hood area (sq ft): Calculated hood coverage area.

Identify Input Parameters
4 parameters
Hood length (ft) = 10, Hood width (ft) = 4, Number of deep-fat fryers = 2, Number of grills/griddles = 1 = 6 input(s) provided
Calculate Total nozzles required
Total nozzles required
6 = 6
Calculate Appliance nozzles
Appliance nozzles
4 = 4
Calculate Plenum nozzles
Plenum nozzles
1 = 1