Kidde Fire Protection 400 Series, Руководство по проектированию, установке, эксплуатации и техническому обслуживанию

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General Information
06-237518-001 1-5 July 2018
1-3.2.1 Oxygen Concentration Above or Below Sea Level
At altitudes different than sea level, atmospheric pressure can be calculated using the following
equation:
P(h) = 14.7 (1 - 6.88x10-6 h)5.25588
The partial pressure of oxygen at altitude h is, therefore:
PO2 = 0.21 P(h)
where
h = Altitude above sea level, ft
P(h) = Atmospheric pressure at altitude h, psi
PO2 = Partial pressure of oxygen, psi
The partial pressure of oxygen in an enclosure after the discharge of a gaseous agent system
is given by
PO2,POST-DISCHARGE = 0.21(1-C/100) PO2
where C is concentration, vol %.
Therefore, interpreting the "sea level equivalent" requirement with respect to egress provisions
from a protected space requires that the local altitude be known.
Table 1-2. Egress Time Limits for Spaces Flooded with an Kidde IGS Agent
Agent Conc.
vol %
% O
2
at
Sea Level
P
O2
, psi
Allowed Occupancy
Egress Time
Limit
C < 43 %O
2
> 12 P
O2
> 1.78 Normally occupied 5 min
43 < C < 52 12 > %O
2
> 10 1.78 > P
O2
> 1.47 Normally occupied 3 min
52 < C < 62 10 > %O
2
> 8 1.47 > P
O2
> 1.18 Not normally occupied 30 s
C > 62 %O
2
< 8 P
O2
< 1.18 Unoccupied areas only n/a