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Definition
Carbon dioxide is a clean, non-corrosive, non-flammable gas which extinguishes fire by
diluting flammable mixtures of air and gas or vapor to proportions below their flammable or explosive
limits. It is especially valuable where other extinguishing mediums might damage stock or equipment.
Types of Gas Storage
SimplexGrinnell installs carbon dioxide systems with either of two forms of
storage for the fire extinguishing gas: in high-pressure non-refrigerated storage cylinders or in
low-pressure refrigerated pressure vessels. It is stored as a liquid and expands at a ratio which
produces 450 cubic feet of fire-smothering gas for each cubic foot of liquid storage.
Design of Carbon Dioxide System
Because of its expansive force, carbon dioxide penetrates every nook
and corner of the enclosed space into which it is discharged, seeking out every place where a flammable
mixture might exist. Carbon dioxide systems are so designed and the piping so proportioned as to prevent
freezing due to expansion in the pressure vessel, valves, piping or discharge nozzles. Since carbon
dioxide does not deteriorate in storage, the effectiveness of the gas is just as great the day the system
is needed as it was the day the storage vessel was filled. Scheduled checking of cylinder weight or
reading of gauge on the low-pressure storage is all that is required to be sure of an available carbon
dioxide supply when needed.
System's Capacity
Two or more spaces may be protected with a single storage supply through the use of
selector valves. In such installations, the required storage capacity is determined by the largest
hazard to be protected.
Methods of Application
The three standard methods of application are known as Total Flooding, Local
Application, and Extended Discharge.
Total Flooding Application is flooding the entire space with carbon dioxide and is generally used when
protecting enclosed or semi-enclosed spaces.
Local Application is applying carbon dioxide directly on one or more hazards where total flooding of
the entire space is impractical.
The Extended Discharge type system discharges at an initially high rate followed by a longer discharge
at a lower rate for either total flooding or local application. This method is used for the protection
of enclosed or semi-enclosed rotating electric equipment and other types of deep-seated smoldering fires
that may re-ignite after the flame has been extinguished.
Auxiliary Equipment
Alarms, indicating lamps and annunciators may be automatically operated by a
pneumatic switch (circuit closer) whenever carbon dioxide is discharged by automatic detector operation.
A pneumatic switch may also be used to stop conveyors, mixers, blowers, ventilation systems, etc.
Both high-pressure and low-pressure systems are equipped with means for manual release if fire is
detected before automatic detectors actuate the system.
Doors, windows, dampers of forced ventilation ducts or openings, and shut-off valves in the piping to
gas or liquid fired burners or heaters may be closed with a pneumatic release operated by the pressure
from the carbon dioxide systems.
Small size openings that cannot be fitted with dampers may be screened with carbon dioxide gas by
use of special nozzles.
 Dry Chemical Systems
Foam Protection
Gaseous Systems
Pilotex® Ultra High Speed Deluge System
Water Spray Systems
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Fire
Fire 