3.1 A means should be provided for manually starting
each pump from the operating compartment. Fault alarms should be provided
to indicate in the operating compartment when electric power is not
available to the pumps.
3.2 All systems should be provided with a means
for manually starting the sprinkler pump at a readily accessible position
close to the pump such that access and operating means are located
outside the space being protected.
3.3 Means should be provided to either automatically
exhaust trapped air from the sprinkler pump casing or prime the sprinkler
pump from the operating compartment under all operating conditions.
3.4 Means should be provided to indicate the following
in the operating compartment:
-
.1 sprinkler system pressure normal (for constantly
pressurised system only);
-
.2 sprinkler system operating (pump running);
and
-
.3 sprinkler system failure (loss of pressure).
3.5 A gauge should be provided in the operating
compartment to indicate sprinkler main pressure.
3.6 Pump, pipe and system sizing
3.6.1 Except as specified in 3.6.2, pumps, piping
and other system supply components should be sized and arranged so
as to be capable of maintaining within one minute of system activation
a minimum flow corresponding to the simultaneous operation of sprinklers
in the following hydraulically most demanding design areas:
-
.1 for manual systems with open nozzles - two
horizontally adjacent sprinkler sections but not less than 280 m2;
-
.2 for manual system with fusible element nozzles
- 280 m2;
-
.3 for wet pipe systems - 150 m2; and
-
.4 for dry pipe and combination systems - 200
m2.
3.6.2 For all types of systems, the design area
can be reduced to the maximum size of the largest space within fire
resisting divisions (30 min or greater) on a single deck area.
3.7 For systems other than those permitted under 2.4, the water discharge rate should not
be less than 5 l/m2/min.
3.8 In automatic systems, sprinkler pumps should
start upon loss of system pressure.
3.9 A sprinkler pump should not be located in
any space protected by the sprinkler system it serves.
3.10 There should be not less than two sources
of power supply for the seawater pump and automatic alarm and detection
system. Where the sources of power for the pump are electrical, these
should be a main generator and an emergency source of power. One supply
for the pump should be taken from the main switchboard, and one from
the emergency switchboard by separate feeders reserved solely for
that purpose. The feeders should be so arranged as to avoid galleys,
machinery spaces and other enclosed spaces of high fire risk except
in so far as it is necessary to reach the appropriate switchboards,
and should be run to an automatic changeover switch situated near
the sprinkler pump. This switch should permit the supply of power
from the main switchboard so long as a supply is available therefrom,
and be so designed that upon failure of that supply it would automatically
change over to the supply from the emergency switchboard. The switches
on the main switchboard and the emergency switchboard should be clearly
labelled and normally kept closed. No other switch should be permitted
in the feeders concerned. One of the sources of power supply for the
alarm and detection system should be emergency source. Where one of
the sources of power for the pump is an internal combustion engine,
it should, in addition to complying with the provisions of 3.9, be
so situated that a fire in any protected space would not affect the
air supply to the machinery.
3.11 The sprinkler system should have a connection
from the ship's fire main by way of a lockable screw-down non-return
valve at he connection which would prevent a backflow from the sprinkler
system to the fire main.
3.12 Primary power for sprinkler pumps should
be electrical motors. Emergency sources of power for sprinkler pumps
should consist of power from an emergency generator. Alternatively,
a dedicated diesel-driven pump may be provided as an emergency source
of power.
3.13 Category A craft having a wet pipe sprinkler
system may have a hydropneumatic tank in lieu of an emergency source
of power for the sprinkler pumps. The tank should be sized for 1-minute
flow at the required discharge rate over the design area.