User's Manual
Design
P/N 81-CO2MAN-001 3-59 September 2013
3-11.2 Main and Reserve Supplies
A reserve agent supply provides a means of rapidly returning the system to its ready state after
a fire or discharge event. A system of controls and valves is used to select a secondary agent
supply and to provide continuous protection while the discharged cylinders are refilled.
Occasionally, the reserve supply is also used to provide a "second shot" of agent during the
same fire event.
The reserve supply shall be equal to the main supply (calculated in Paragraph 3-11.1) and shall
be permanently connected to the piping, except where the authority having jurisdiction permits
an unconnected reserve.
It is strongly recommended to provide a reserve agent supply when multiple hazards are
protected from a common bank of cylinders using directional valves (See Paragraph 3-8).
3-11.3 Cylinder Location
The cylinder location is an important factor in system design, as this will affect the installation
of pipe, mechanical or pneumatic detection lines, and remote cable pull stations.
The carbon dioxide cylinders must be located as close to the hazard area as possible. Storage
containers and accessories shall be so located and arranged that inspection, testing,
recharging, and other maintenance is facilitated and interruption to protection is held to a
minimum. Storage containers shall not be located where they will be exposed to:
• fire or explosion
• direct sunlight
• outdoor weather
• mechanical, chemical, or other damage.
When excessive climatic or mechanical exposures are expected, suitable guards or enclosures
shall be provided.
From Equation (34):
Where is the Quantity of Cylinders Required and is the Selected Cylinder Capacity.
To minimize the quantity of cylinders needed, select the largest possible cylinder size:
= 100 lb.
=
l = 473 100
= 4.73
5 cylinders
From Equation (35):
Where is the Total Quantity of Agent Supplied.
= x
= 500 lb.
n
cyl
W
min,sys
W
cyl
=
n
cyl
W
cyl
W
cyl
n
cyl
W
min,sys
W
cyl
n
cyl
n
cyl
n
cyl
W
sys
n
cyl
W
cyl
=
W
sys
W
sys
n
cyl
W
cyl
W
sys