User's Manual

Design
September 2013 3-12 P/N 81-CO2MAN-001
EXAMPLE 3 - TOTAL FLOODING FOR SURFACE FIRES - Uncloseable Openings
Determine the loss rate through a 1 ft. x 1 ft. opening in the wall of an enclosure. The
midpoint of the opening is 5 feet below the ceiling, and the system is designed to achieve a
34% concentration.
From Equation (4):
Where is the Effective Leakage Area and
is the Total Leakage Area.
From Equation (5):
Where is the Enclosure Leakage Rate and is the Leakage Rate from Figure 3-2.
Referring to Figure 3-2, move along the x-axis to the 5 ft. height. Move up at this point to
the 34% curve, which must be estimated between the 30% and 40% curves, and then read
over to the vertical axis. The approximate leakage rate is determined to be 15
lb./min/
ft.
2
.
=7.5 lb./min or say 8 lb./min
A
L
A
O
2=
A
L
A
O
A
O
11=
A
O
1 ft
2
=
A
L
A
O
2=
A
L
12=
A
L
0.5 ft.
2
=
q
L
LA
L
=
q
L
L
L
q
L
LA
L
=
q
L
15 0.5=
q
L