100: Carbon Dioxide (CO2) Fire Suppression

Carbon Dioxide (CO2) is a highly efficient extinguishing agent and effect on the oxygen and heat sides of fire triangle. Carbon dioxide is a member of the inert gas family but due to its special features, has a different fire extinguishing system. CO2 is suitable for fire classes of B and C.

CO2 properties:

• Natural inert gas
• Colorless
• Odourless (slightly pungent odour at high concentrations)
• Non-conductive
• Transportation and storage in liquid form
• 1.5 times heavier than air (density of 1.87 kg/m3 ) at +15°C and atmospheric pressure

Advantages:

• Eco-friendly
• High availability
• Reasonable price

Disadavntage:

• Danger to life (carbon dioxide concentration more than 5% volume)
• Forming the mist after releasing the gas.

CO2 is used in both types of extinguishers:

1- Portable extinguisher

• Hand held
• Wheeled)

2- Fixed extinguisher (stationary system)

• Single sector
• Multi sector

Component of fixed extinguishing systems:

1- Mechanical parts

• Cylinder rack (wall or floor)
• Cylinder bank
  • Main / Reserve
  • Master / Slave
• Cylinder (control/pilot, CO2/N2)
  • e.g. CO2 cylinder
    • Capacity: 67.5 / 80 liter
    • Working pressure: 200 bar
    • Test pressure: 300 bar
    • System pressure: 58 bar
  • e.g. N2 cylinder
    • Capacity: 5 / 10liter
    • Working pressure: 200 bar
    • Test pressure: 300 bar
• Cylinder valve
• Weighing device + Limit switch (for CO2 cylinder)
• Pressure gauge with electrical switching contact (for pilot N2 cylinder)
• Triggering device (electrical/pneumatic/manual)
• Electrical actuator
• Pneumatical actuator
• Solenoid actuator
• Control (pilot) hose and adapter
• Discharge hose and adapter
• Manifold
• Check valve
• Bleed valve
• Safety valve
• Pressure reduction valve
• Selector valve (Three-way valve)
• Mechanical blocking device
• Time delay device (Non-electrical)
• Valve with test clutch, test device
• Odouriser Cartridge
• Distribution pipe network, fittings, couplings, supports, brackets, rods, nuts, bolts, dowels
• Nozzle
• Pressure relief damper (vent)
• Pressure-controlled, electrical switching contact
• Electrical switching contact
• Pneumatic signal horn
• Safety sign

2- Electrical parts

• Fire extinguishing control panel
• Fire detector
• Alarm indicator
• Manual release
• Manual hold
• Sounder flasher
• Warning panel

Related standards:

• NFPA 12
• VdS 2093
• CEA 4007
• NFPA 72