tanks with or without interior floating pans. Select
second bracketed option for floating roof tanks.
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Area shall be over the [entire liquid surface] [annular ring seal between
the tank wall and foam dam] as required by NFPA 11.
2.2.6
Friction Losses
Calculate losses in pipe in accordance with the Hazen-Williams Formula with
'C' value of 100 for steel pipe, 150 for copper tube, and 140 for cement
lined ductile iron pipe.
2.2.7
Location of Foam Chambers
Locate chambers on the tank wall just below the roof joint as required by
NFPA 11. Where two or more chambers are required, they shall be equally
spaced around the tank circumference.
2.2.8
Water Supply
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NOTE: Select first option if the water supply is
provided directly from the base water distribution
system and show or specify the point of connection.
Select second option if the water supply is provided
from fire pumps dedicated to the AFFF system, which
are taking suction from a static water source.
Select third option if the water supply is provided
from booster fire pumps being supplied from the base
water distribution system, and show or specify the
point of connection to the base system. Edit
Section 13920, "Fire Pumps" and include as part of
the project specification when using the second or
third option.
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[Base hydraulic calculations on a static pressure of [_____] kPa (gage)
pounds per square inch gage (psig) with [_____] L/m gpm being available at
a residual pressure of [_____] kPa (gage) psig at the point [indicated] [of
connection with the base water distribution system].]
[Base hydraulic calculations on [_____] fire pump(s) running.
Provide fire
pumps as specified in Section 13920 FIRE PUMPS.]
[Base hydraulic calculations on [_____] fire pump(s) running, with a
suction supply having a static pressure of [_____] kPa (gage) psigwith
[_____] L/m gpm being available at a residual pressure of [_____] kPa (gage)
psig at the point [indicated] [of connection with the base water
distribution system]. Provide fire pumps as specified in Section 13920
FIRE PUMPS.]
2.2.9
Duration of Discharge
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NOTE: For discharge duration, consult NFPA 11 and
NFPA 30.
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SECTION 13957N
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