CO 2 System – Calculation of necessary quantities

CO 2 System – Calculation of necessary quantities


CO2 System - Calculation of necessary quantities


Where to use co2 ?

  • Unoccupied areas of electronic and technical rooms.
  • Transformer Rooms
  • Battery and UPS Rooms

CO2 System Operation


  • Fire Detectors sense fire conditions in the hazard area ( Smoke , heat , gas, air sampling ...)
  • Electrical signal is sent through the fire alarm control panel FACP to the control head
  • Control head releases CO2 from the cylinders and is delivered through a fixed piping network to discharge nozzles in 1 min for surface fires and less than 7 mm for deep= seated fires

Things to consider during design of a carbon dioxide fire fighting system 

After we determine which areas will be fire protected with carbon dioxide , we must estimate the most probable type of fire that will develop upon fire initiation. Based on NFPA 12 two major types of fire exist

  • Surface Fires
  • Deep seated Fire

Base Quantity of CO2 = Area ᙭ Height ᙭ Volume Factor


TO Determine the Volume Factor


  1. Type ( 1 ) surface fires
Once the net volume is known, we proceed to determine the design concentration of 
dioxide that is required for the type of flammable material involved. In no case shall a concentration less than 34% be used. 


For a design concentration of 34%, NFPA 12 stipulated flooding factors will have to be applied as a minimum :


Table Type ( 1 )




2-  Type ( 2 ) Deep seated fires



Example :
  • Deep seatad Fire ( type 2 )
  • Area = 131.1 m2
  • Height = 3.5 m
  • Volume Factor = 1.33 Kg CO2 / M3 


Base Quantity of CO2 = Area ᙭ Height ᙭ Volume Factor

Base Quantity of CO2 = 131.1 ᙭ 3.5 ᙭ 1.33 = 610.27 Kg

Assume : the cylinder containing  = 45.4 kg

Number of Cylinder = 14 Cylinder



Next subject , we will explain the design of pipes for CO2 SYSTEM



THANK YOU



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