Tyco Fire Suppression & Building Products ANSUL AQUASONIC, Design, Installation, Recharge, And Maintenance Manual

Page: 54 / 141

SECTION II
3-1-2010 Page 2-10
RELIEF VENTING
Relief venting requirements for the AQUASONIC system
are very minimal. In most cases normal compartment
leakage will be sufficient to accomplish the relief venting
requirements.
The relief venting requirements in square inches can be
determined by multiplying 12.8 times the number of atomiz-
ers divided by the square root of the maximum allowable
wall strength in pounds per square foot.
The formula may be written as follows (imperial):
12.8 x Na
________
A =
P
Where:
A = The Free Vent Area in square inches.
Na = The number of atomizers in the space.
P = The maximum allowable wall strength in lb/ft
2
of
the weakest surface (walls, ceiling, floor, doors,
windows, etc.) of the enclosure.
Note: Where the maximum allowable wall strength is not
known, a conservative value of 5 pounds per squre foot
shall be used.
Example:
For an enclosure containing 4 atomizers and a maximum
allowable wall strength of 5 psf, the free vent area is as
follows:
12.8 x 4
________
5
= 22.8 in
2
The formula may be written as follows (metric):
57.248 x Na
__________
A =
P
Where:
A = The Free Vent Area in centimeters.
Na = The number of atomizers in the space.
P = The maximum allowable wall strength in millibar of
the weakest surface (walls, ceiling, floor, doors,
windows, etc.) of the enclosure.
Note: Where the maximum allowable wall strength is not
known, a conservative value of 2.394 millibar shall be used.
Example:
For an enclosure containing 4 atomizers and a maximum
allowable wall strength of 2.394 millibar, the free vent area
is as follows:
52.248 x 4
________
2.394
= 148 cm
2
General Information