CEA 4001 - Pressure and flow requirements for precalculated systems

41
T
Table 6: Design criteria for roof sprinklers with in-rack protection
Storage
methods
Maximum permitted storage height above highest level of
intermediate sprinklers
(1)
m
Minimum
design
density
mm/min
Area of
operation
(wet
or pre-
action
system
(2
)
m²
category I
category II
category III
category IV
ST4 palletized
rack
3,5
3,5
2,2
2,6
3,2
3,5
1,6
2,0
2,3
2,7
7,5
10,0
12,5
15,0
260
ST5 and ST6
solid
or slatted
shelves
4,7
5,7
3,4
4,2
5,0
2,2
2,6
3,2
1,6
2,0
2,3
2,7
3,0
7,5
10,0
12,5
15,0
17,5
260
NOTE 1: the vertical distance from the highest level of in-rack sprinklers to the roof or ceiling sprinklers,
minus1m.
NOTE
2: dry and alternate systems should be avoided on High Hazard storages especially with the
more
combustible products (the higher categories) and the higher storages. Should it nonetheless
be
necessary to install a dry or alternate system, the area of operation shall be increased by 25 %.
6.3 Pressure and flow requirements for precalculated systems
6.3.1 LH and OH systems
The water supply shall be capable of providing the flows and pressures at each installation control valve set
as specified in Table 7. The pressure loss due to friction and static between the water supply and each
control valve set shall be calculated separately.
Table 7: Pressure and flow requirements for precalculated LH and OH systems
Hazard Class
Flow
l/min
Pressure at the
control valve
set
bar
Flow (maximum
demand
flow)
l/min
Pressure at the control
valve
set
(at maximum
demand flow)
bar
LH
225
2,2+Ps
-
-
OH1 Wet and pre-action
375
1,0+Ps
540
0,7+Ps
OH1 Dry and alternate
OH2 Wet and pre-action
725
1,4+Ps
1 000
1,0+Ps
OH2 Dry and alternate
OH3 Wet and pre-action
1 100
1,7+Ps
1 350
1,4+Ps
OH3 Dry and alternate
OH4
Wet and pre-action
1 800 2,0+Ps 2 100 1,5+Ps
NOTE : Ps is the pressure difference equivalent to the height of the highest sprinkler above the
control valve set.