In addition to the requirements in section 3, systems designed
with this approach should comply with paragraphs 4.1 to 4.10.
4.1 Wet pipe, dry pipe and pre-action systems
should be designed for simultaneous coverage of the hydraulically
most demanding area at the minimum water discharge density given in
tables 4-1 to 4-3. The minimum operating pressure of any sprinkler
should be 0.05 MPa.
4.2 Deluge systems should be designed for the
simultaneous activation of the two adjacent deluge sections with the
greatest hydraulic demand at the minimum water discharge density given
in tables 4-1 to 4-3. The minimum operating pressure of any sprinkler
should be 0.12 MPa.
Table 4-1 Minimum required water
discharge density and area of coverage for decks having a free height equal to or
less than 2.5 m
|
Type of system
|
Minimum water discharge density (mm/min)
|
Minimum coverage area
|
| Wet pipe system
|
6.5
|
280 m2
|
| Dry pipe or pre-action system
|
6.5
|
280 m2
|
| Deluge system
|
5
|
2 × 20m x B1
|
Table 4-2 Minimum required water
discharge density and area of coverage for decks having a free height in excess of
2.5 m but less than 6.5 m
|
Type of system
|
Minimum water discharge density (mm/min)
|
Minimum coverage area
|
| Wet pipe system
|
15
|
280 m2
|
| Dry pipe or pre-action system
|
15
|
365 m2
|
| Deluge system
|
10
|
2 × 20 m x B1
|
Table 4-3 Minimum required water
discharge density and area of coverage for decks having a free height in excess of
6.5 m but less than 9.0 m
|
Type of system
|
Minimum water discharge density (mm/min)
|
Minimum coverage area
|
| Wet pipe system
|
20
|
280 m2
|
| Dry pipe or pre-action system
|
20
|
365 m2
|
| Deluge system
|
15
|
2 × 20 m x B1
|
1
B = full breadth of the protected
space.
4.3 Automatic sprinklers or nozzles intended for
decks with a free height equal to or less than 2.5 m should have a
nominal operating temperature range between 57°C and 79°C
and standard response characteristics. If required by ambient conditions,
higher temperature ratings may be acceptable.
4.4 Automatic sprinklers or nozzles intended for
decks with a free height in excess of 2.5 m and hoistable decks that
can be raised above 2.5 m should have a nominal operating temperature
range between 121°C and 149°C and standard response characteristics.
4.5 Sprinklers or nozzles should be positioned
at or within 0.6 m of the underside of the deck, in order to distribute
water over and between all vehicles or cargo in the area being protected.
Automatic sprinklers or nozzles should be positioned and located so
as to provide satisfactory performance with respect to both activation
time and water distribution. The maximum horizontal spacing between
nozzles or sprinklers should not exceed 3.2 m.
4.6 Only upright sprinklers or nozzles are allowed
for dry pipe or pre-action systems.
4.7 For wet pipe and dry pipe sprinkler systems,
fire detection systems should be installed in accordance with the
requirements of SOLAS regulation II-2/20.4.
4.8 For manual deluge systems, automatic deluge
systems and pre-action systems, fire detection systems should be provided
complying with the International Code for Fire Safety Systems (FSS Code) and the following additional requirements:
-
.1 the detection system should consist of flame,
smoke or heat detectors of approved types, arranged as described below.
The flame detectors should be installed under fixed continuous decks
according to the limitation and application defined by the maker and
the approval certificate. The smoke and heat detector arrangement
shall comply with the FSS Code. Smoke detectors
with a spacing not exceeding 11 m or heat detectors with a spacing
not exceeding 9 m should be installed under hoistable ramps;
-
.2 the detection system should ensure rapid operation
while consideration should also be given to preventing accidental
release. The area of coverage of the detection system sections should
correspond to the area of coverage of the extinguishing system sections.
The following arrangements are acceptable:
-
.1 set-up of approved flame detectors and approved
smoke detectors or heat detectors; or
-
.2 set-up of approved smoke detectors and approved
heat detectors; other arrangements can be accepted by the Administration;
-
.3 for automatic deluge systems and pre-action
systems, the discharge of water should be controlled by the detection
system. The detection system should provide an alarm upon activation
of any single detector and discharge if two or more detectors activate.
The Administration may accept other arrangements; and
-
.4 automatically released systems should also
be capable of manual operation (both opening and closing) of the section
valves. Means should be provided to prevent the simultaneous release
of multiple sections that result in water-flow demand in excess of
the pumping system design capacity. The automatic release may be disconnected
during on- and off-loading operations, provided that this function
is automatically reconnected after a pre-set time being appropriate
for the operations in question.
4.9 Where beams project more than 100 mm below
the deck, the spacing of spot-type heat detectors at right angles
to the direction of the beam travel should not be more than two thirds
of the spacing permitted under chapter 9 of
the FSS Code.
4.10 Where beams project more than 460 mm below
the deck and are more than 2.4 m on centre, detectors should be installed
in each bay formed by the beams.