Fire and Water Flow

What’s the best size for an “attack line?”
What factors are the highest priority on your department?
  • Maximum flow
  • Maximum mobility
  • Speed-How fast and how much
  • Ease of deployment and pickup
  • Personnel available
  • Water supply available
     
Larger Attack Hose Lines Equal
  • Higher initial attack flow capability
  • Less friction loss
  • Longer hose lay capability
  • Using more of pumps capacity

Hard Suction Hose

Higher Flows Equal
  • Quicker fire knockdown
  • Personnel spend less time in “combat”
  • More lives saved
  • More property saved
     
Friction Loss  “Rule of Thumb” Hydraulics
  • 1 3/4" Hose - 30 lbs. friction loss per 100 ft.
  • 2 1/2" Hose - 10 lbs. friction loss per 100 ft.
  • Optimal Fog Nozzle pressure is 100 PSI
  • Optimal Solid bore Nozzle pressure is 60 PSI

Hard Suction Hose

Nozzle Basics Discharge
Smooth Bore Nozzle - Handline 50 PSI
Smooth Bore Nozzle - Master Stream 80 PSI
Combination Nozzle - (all types) 100 PSI

Hard Suction Hose

National Fire Academy Formula for Quick Size-up
GPM = L x W / 3                    L = Length       W = Width
Fire knockdown in 30 seconds or less
Multiply GPM by number of floors involved
Can be adjusted for actual % of involvement
Choose appropriate size & number of attack lines based on GPM required & other situational factors

Hard Suction Hose

Iowa State University Formula
GPM = L x W x H / 100                    L = Length       W = Width      H = Height
Fire knockdown in 60 seconds or less
Normally for enclosed areas
Can be used in pre-planning water requirements for a building or room

Hard Suction Hose

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Fire Hose Basics

Fire Hose Appliances and Hose Tools

Fire Line

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