11.4.1 Ships in which the carriage of flammable
products is intended shall be fitted with fixed dry chemical powder
fire-extinguishing systems, approved by the Administration based on
the guidelines developed by the Organizationfootnote, for the purpose of firefighting on the
deck in the cargo area, including any cargo liquid and vapour discharge
and loading connections on deck and bow or stern cargo handling areas,
as applicable.
11.4.2 The system shall be capable of delivering
powder from at least two hand hose lines, or a combination of monitor/hand
hose lines, to any part of the exposed cargo liquid and vapour piping,
load/unload connection and exposed gas process units.
11.4.3 The dry chemical powder fire-extinguishing
system shall be designed with not less than two independent units.
Any part required to be protected by 11.4.2 shall be capable of being
reached from not less than two independent units with associated controls,
pressurizing medium fixed piping, monitors or hand hose lines. For
ships with a cargo capacity of less than 1,000 m3, only
one such unit need be fitted. A monitor shall be arranged to protect
any load/unload connection area and be capable of actuation and discharge
both locally and remotely. The monitor is not required to be remotely
aimed, if it can deliver the necessary powder to all required areas
of coverage from a single position. One hose line shall be provided
at both port- and starboard side at the end of the cargo area facing
the accommodation and readily available from the accommodation.
11.4.4 The capacity of a monitor shall be not
less than 10 kg/s. Hand hose lines shall be non-kinkable and be fitted
with a nozzle capable of on/off operation and discharge at a rate
not less than 3.5 kg/s. The maximum discharge rate shall allow operation
by one man. The length of a hand hose line shall not exceed 33 m.
Where fixed piping is provided between the powder container and a
hand hose line or monitor, the length of piping shall not exceed that
length which is capable of maintaining the powder in a fluidized state
during sustained or intermittent use, and which can be purged of powder
when the system is shut down. Hand hose lines and nozzles shall be
of weather-resistant construction or stored in weather resistant housing
or covers and be readily accessible.
11.4.5 Hand hose lines shall be considered to
have a maximum effective distance of coverage equal to the length
of hose. Special consideration shall be given where areas to be protected
are substantially higher than the monitor or hand hose reel locations.
11.4.6 Ships fitted with bow/stern load/unload
connections shall be provided with independent dry powder unit protecting
the cargo liquid and vapour piping, aft or forward of the cargo area,
by hose lines and a monitor covering the bow/stern load/unload complying
with the requirements of 11.4.1 to 11.4.5.
11.4.7 Ships intended for operation as listed
in 1.1.10 shall be subject to special consideration.
11.4.8 After installation, the pipes, valves,
fittings and assembled systems shall be subjected to a tightness test
and functional testing of the remote and local release stations. The
initial testing shall also include a discharge of sufficient amounts
of dry chemical powder to verify that the system is in proper working
order. All distribution piping shall be blown through with dry air
to ensure that the piping is free of obstructions.