Part B – Prevention of Fire and
Explosion
Regulation 4 – Probability
of ignition
1 Purpose
The purpose of this regulation is to prevent the ignition
of combustible materials or flammable liquids. For this purpose, the
following functional requirements shall be met:
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.1 means shall be provided to control leaks of
flammable liquids;
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.2 means shall be provided to limit the accumulation
of flammable vapours;
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.3 the ignitability of combustible materials shall
be restricted;
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.4 ignition sources shall be restricted;
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.5 ignition sources shall be separated from combustible
materials and flammable liquids; and
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.6 the atmosphere in cargo tanks shall be maintained
out of the explosive range.
2 Arrangements for oil fuel, lubrication oil and
other flammable oils
2.1
Limitations in the use of oils as fuel
The following limitations shall apply to the use of oil
as fuel:
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.1 except as otherwise permitted by this paragraph,
no oil fuel with a flashpoint of less than 60°C shall be used;footnote
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.2 in emergency generators oil fuel with a flashpoint
of not less than 43°C may be used;
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.3 the use of oil fuel having a flashpoint of
less than 60°C but not less than 43°C may be permitted (e.g.,
for feeding the emergency fire pump’s engines and the auxiliary
machines which are not located in the machinery spaces of category
A) subject to the following:
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.3.1 fuel oil tanks except those arranged in double
bottom compartments shall be located outside of machinery spaces of
category A;
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.3.2 provisions for the measurement of oil temperature
are provided on the suction pipe of the oil fuel pump;
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.3.3 stop valves and/or cocks are provided on
the inlet side and outlet side of the oil fuel strainers; and
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.3.4 pipe joints of welded construction or of
circular cone type or spherical type union joint are applied as much
as possible; and
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.4 in cargo ships the use of fuel having a lower
flashpoint than otherwise specified in paragraph 2.1, for example
crude oil, may be permitted provided that such fuel is not stored
in any machinery space and subject to the approval by the Administration
of the complete installation.
2.2
Arrangements for oil fuel
In a ship in which oil fuel is used, the arrangements for
the storage, distribution and utilization of the oil fuel shall be
such as to ensure the safety of the ship and persons on board and
shall at least comply with the following provisions.
2.2.1
Location of oil fuel systems
As far as practicable, parts of the oil fuel system containing
heated oil under pressure exceeding 0.18 N/mm2 shall not
be placed in a concealed position such that defects and leakage cannot
readily be observed. The machinery spaces in way of such parts of
the oil fuel system shall be adequately illuminated.
2.2.2
Ventilation of machinery spaces
The ventilation of machinery spaces shall be sufficient
under normal conditions to prevent accumulation of oil vapour.
2.2.3
Oil fuel tanks
2.2.3.1 Fuel oil, lubrication oil and other flammable
oils shall not be carried in forepeak tanks.
2.2.3.2 As far as practicable, oil fuel tanks
shall be part of the ships structure and shall be located outside
machinery spaces of category A. Where oil fuel tanks, other than double
bottom tanks, are necessarily located adjacent to or within machinery
spaces of category A, at least one of their vertical sides shall be
contiguous to the machinery space boundaries, and shall preferably
have a common boundary with the double bottom tanks, and the area
of the tank boundary common with the machinery spaces shall be kept
to a minimum. Where such tanks are situated within the boundaries
of machinery spaces of category A they shall not contain oil fuel
having a flashpoint of less than 60°C. In general, the use of
free-standing oil fuel tanks shall be avoided. When such tanks are
employed their use shall be prohibited in category A machinery spaces
on passenger ships. Where permitted, they shall be placed in an oil-tight
spill tray of ample size having a suitable drain pipe leading to a
suitably sized spill oil tank.
2.2.3.3 No oil fuel tank shall be situated where
spillage or leakage therefrom can constitute a fire or explosion hazard
by falling on heated surfaces.
2.2.3.4 Oil fuel pipes, which, if damaged, would
allow oil to escape from a storage, settling or daily service tank
having a capacity of 500 l and above situated above the double
bottom, shall be fitted with a cock or valve directly on the tank
capable of being closed from a safe position outside the space concerned
in the event of a fire occurring in the space in which such tanks
are situated. In the special case of deep tanks situated in any shaft
or pipe tunnel or similar space, valves on the tank shall be fitted,
but control in the event of fire may be effected by means of an additional
valve on the pipe or pipes outside the tunnel or similar space. If
such an additional valve is fitted in the machinery space it shall
be operated from a position outside this space. The controls for remote
operation of the valve for the emergency generator fuel tank shall
be in a separate location from the controls for remote operation of
other valves for tanks located in machinery spaces.
2.2.3.5 Safe and efficient means of ascertaining
the amount of oil fuel contained in any oil fuel tank shall be provided.
2.2.3.5.1 Where sounding pipes are used, they
shall not terminate in any space where the risk of ignition of spillage
from the sounding pipe might arise. In particular, they shall not
terminate in passenger or crew spaces. As a general rule, they shall
not terminate in machinery spaces. However, where the Administration
considers that these latter requirements are impracticable, it may
permit termination of sounding pipes in machinery spaces on condition
that all of the following requirements are met:
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.1 an oil-level gauge is provided meeting the
requirements of paragraph 2.2.3.5.2;
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.2 the sounding pipes terminate in locations remote
from ignition hazards unless precautions are taken, such as the fitting
of effective screens, to prevent the oil fuel in the case of spillage
through the terminations of the sounding pipes from coming into contact
with a source of ignition; and
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.3 the termination of sounding pipes are fitted
with self-closing blanking devices and with a small-diameter self-closing
control cock located below the blanking device for the purpose of
ascertaining before the blanking device is opened that oil fuel is
not present. Provisions shall be made so as to ensure that any spillage
of oil fuel through the control cock involves no ignition hazard.
2.2.3.5.2 Other oil-level gauges may be used in
place of sounding pipes subject to the following conditions:
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.1 in passenger ships, such gauges shall not require
penetration below the top of the tank and their failure or overfilling
of the tanks shall not permit release of fuel; and
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.2 in cargo ships, the failure of such gauges
or overfilling of the tank shall not permit release of fuel into the
space. The use of cylindrical gauge glasses is prohibited. The Administration
may permit the use of oil-level gauges with flat glasses and self-closing
valves between the gauges and fuel tanks.
2.2.3.5.3 The means prescribed in paragraph 2.2.3.5.2
which are acceptable to the Administration shall be maintained in
the proper condition to ensure their continued accurate functioning
in service.
2.2.4
Prevention of overpressure
Provisions shall be made to prevent overpressure in any
oil tank or in any part of the oil fuel system, including the filling
pipes served by pumps on board. Air and overflow pipes and relief
valves shall discharge to a position where there is no risk of fire
or explosion from the emergence of oils and vapour and shall not lead
into crew spaces, passenger spaces nor into special category spaces,
closed ro-ro cargo spaces, machinery spaces or similar spaces.
2.2.5
Oil fuel piping
2.2.5.1 Oil fuel pipes and their valves and fittings
shall be of steel or other approved material, except that restricted
use of flexible pipes shall be permissible in positions where the
Administration is satisfied that they are necessary.footnote Such flexible pipes and end attachments shall
be of approved fire-resisting materials of adequate strength and shall
be constructed to the satisfaction of the Administration. For valves,
fitted to oil fuel tanks and which are under static pressure, steel
or spheroidal-graphite cast iron may be accepted. However, ordinary
cast iron valves may be used in piping systems where the design pressure
is lower than 7 bar and the design temperature is below 60°C.
2.2.5.2 External high-pressure fuel delivery lines
between the high-pressure fuel pumps and fuel injectors shall be protected
with a jacketed piping system capable of containing fuel from a high-pressure
line failure. A jacketed pipe incorporates an outer pipe into which
the high-pressure fuel pipe is placed, forming a permanent assembly.
The jacketed piping system shall include a means for collection of
leakages and arrangements shall be provided with an alarm in case
of a fuel line failure.
2.2.5.3 Oil fuel lines shall not be located immediately
above or near units of high temperature including boilers, steam pipelines,
exhaust manifolds, silencers or other equipment required to be insulated
by paragraph 2.2.6. As far as practicable, oil fuel lines shall be
arranged far apart from hot surfaces, electrical installations or
other sources of ignition and shall be screened or otherwise suitably
protected to avoid oil spray or oil leakage onto the sources of ignition.
The number of joints in such piping systems shall be kept to a minimum.
2.2.5.4 Components of a diesel engine fuel system
shall be designed considering the maximum peak pressure which will
be experienced in service, including any high pressure pulses which
are generated and transmitted back into the fuel supply and spill
lines by the action of fuel injection pumps. Connections within the
fuel supply and spill lines shall be constructed having regard to
their ability to prevent pressurized oil fuel leaks while in service
and after maintenance.
2.2.5.5 In multi-engine installations which are
supplied from the same fuel source, means of isolating the fuel supply
and spill piping to individual engines, shall be provided. The means
of isolation shall not affect the operation of the other engines and
shall be operable from a position not rendered inaccessible by a fire
on any of the engines.
2.2.5.6 Where the Administration may permit the
conveying of oil and combustible liquids through accommodation and
service spaces, the pipes conveying oil or combustible liquids shall
be of a material approved by the Administration having regard to the
fire risk.
2.2.6
Protection of high temperature surfaces
2.2.6.1 Surfaces with temperatures above 220°C
which may be impinged as a result of a fuel system failure shall be
properly insulated.
2.2.6.2 Precautions shall be taken to prevent
any oil that may escape under pressure from any pump, filter or heater
from coming into contact with heated surfaces.
2.3
Arrangements for lubricating oil
2.3.1 The arrangements for the storage, distribution
and utilization of oil used in pressure lubrication systems shall
be such as to ensure the safety of the ship and persons on board.
The arrangements made in machinery spaces of category A, and whenever
practicable in other machinery spaces, shall at least comply with
the provisions of paragraphs 2.2.1, 2.2.3.3, 2.2.3.4, 2.2.3.5, 2.2.4,
2.2.5.1, 2.2.5.3 and 2.2.6, except that:
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.1 this does not preclude the use of sight-flow
glasses in lubricating systems provided that they are shown by testing
to have a suitable degree of fire resistance; and
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.2 sounding pipes may be authorized in machinery
spaces; however, the requirements of paragraphs 2.2.3.5.1.1 and 2.2.3.5.1.3
need not be applied on condition that the sounding pipes are fitted
with appropriate means of closure.
2.3.2 The provisions of paragraph 2.2.3.4 shall
also apply to lubricating oil tanks except those having a capacity
less than 500 l , storage tanks on which valves are closed during
the normal operation mode of the ship, or where it is determined that
an unintended operation of a quick closing valve on the oil lubricating
tank would endanger the safe operation of the main propulsion and
essential auxiliary machinery.
2.4
Arrangements for other flammable oils
The arrangements for the storage, distribution and utilization
of other flammable oils employed under pressure in power transmission
systems, control and activating systems and heating systems shall
be such as to ensure the safety of the ship and persons on board.
Suitable oil collecting arrangements for leaks shall be fitted below
hydraulic valves and cylinders. In locations where means of ignition
are present, such arrangements shall at least comply with the provisions
of paragraphs 2.2.3.3, 2.2.3.5, 2.2.5.3 and 2.2.6 and with the provisions
of paragraphs 2.2.4 and 2.2.5.1 in respect of strength and construction.
2.5
Arrangements for oil fuel in periodically
unattended machinery spaces
In addition to the requirements of paragraphs 2.1 to 2.4,
the oil fuel and lubricating oil systems in a periodically unattended
machinery space shall comply with the following:
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.1 where daily service oil fuel tanks are filled
automatically, or by remote control, means shall be provided to prevent
overflow spillages. Other equipment which treats flammable liquids
automatically (e.g. oil fuel purifiers) which, whenever practicable,
shall be installed in a special space reserved for purifiers and their
heaters, shall have arrangements to prevent overflow spillages; and
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.2 where daily service oil fuel tanks or settling
tanks are fitted with heating arrangements, a high temperature alarm
shall be provided if the flashpoint of the oil fuel can be exceeded.
3 Arrangements for gaseous fuel for domestic
purpose
Gaseous fuel systems used for domestic purposes shall be
approved by the Administration. Storage of gas bottles shall be located
on the open deck or in a well ventilated space which opens only to
the open deck.
4 Miscellaneous items of ignition sources
and ignitability
4.1
Electric radiators
Electric radiators, if used, shall be fixed in position
and so constructed as to reduce fire risks to a minimum. No such radiators
shall be fitted with an element so exposed that clothing, curtains,
or other similar materials can be scorched or set on fire by heat
from the element.
4.2
Waste receptacles
Waste receptacles shall be constructed of non-combustible
materials with no openings in the sides or bottom.
4.3
Insulation surfaces protected against
oil penetration
In spaces where penetration of oil products is possible,
the surface of insulation shall be impervious to oil or oil vapours.
4.4 Primary deck coverings
Primary deck coverings, if applied within accommodation
and service spaces and control stations, shall be of approved material
which will not readily ignite, this being determined in accordance
with the Fire Test Procedures Code.
5 Cargo areas of tankers
5.1
Separation of cargo oil tanks
5.1.1 Cargo pump-rooms, cargo tanks, slop tanks
and cofferdams shall be positioned forward of machinery spaces. However,
oil fuel bunker tanks need not be forward of machinery spaces. Cargo
tanks and slop tanks shall be isolated from machinery spaces by cofferdams,
cargo pump-rooms, oil bunker tanks or ballast tanks. Pump-rooms containing
pumps and their accessories for ballasting those spaces situated adjacent
to cargo tanks and slop tanks and pumps for oil fuel transfer, shall
be considered as equivalent to a cargo pump-room within the context
of this regulation provided that such pump-rooms have the same safety
standard as that required for cargo pump-rooms. Pump-rooms intended
solely for ballast or oil fuel transfer, however, need not comply
with the requirements of regulation 10.9. The lower portion of the
pump-room may be recessed into machinery spaces of category A to accommodate
pumps, provided that the deck head of the recess is in general not
more than one third of the moulded depth above the keel, except that
in the case of ships of not more than 25,000 tonnes deadweight, where
it can be demonstrated that for reasons of access and satisfactory
piping arrangements this is impracticable, the Administration may
permit a recess in excess of such height, but not exceeding one half
of the moulded depth above the keel.
5.1.2 Main cargo control stations, control stations,
accommodation and service spaces (excluding isolated cargo handling
gear lockers) shall be positioned aft of cargo tanks, slop tanks,
and spaces which isolate cargo or slop tanks from machinery spaces,
but not necessarily aft of the oil fuel bunker tanks and ballast tanks,
and shall be arranged in such a way that a single failure of a deck
or bulkhead shall not permit the entry of gas or fumes from the cargo
tanks into an accommodation space, main cargo control stations, control
station, or service spaces. A recess provided in accordance with paragraph
5.1.1 need not be taken into account when the position of these spaces
is being determined.
5.1.3 However, where deemed necessary, the Administration
may permit main cargo control stations, control stations, accommodation
and service spaces forward of the cargo tanks, slop tanks and spaces
which isolate cargo and slop tanks from machinery spaces, but not
necessarily forward of oil fuel bunker tanks or ballast tanks. Machinery
spaces, other than those of category A, may be permitted forward of
the cargo tanks and slop tanks provided they are isolated from the
cargo tanks and slop tanks by cofferdams, cargo pump-rooms, oil fuel
bunker tanks or ballast tanks, and have at least one portable fire
extinguisher. In cases where they contain internal combustion machinery,
one approved foam-type extinguisher of at least 45l capacity
or equivalent shall be arranged in addition to portable fire extinguishers.
If operation of a semi-portable fire extinguisher is impracticable,
this fire extinguisher may be replaced by two additional portable
fire extinguishers. Accommodation spaces, main cargo control spaces,
control stations and service spaces shall be arranged in such a way
that a single failure of a deck or bulkhead shall not permit the entry
of gas or fumes from the cargo tanks into such spaces. In addition,
where deemed necessary for the safety or navigation of the ship, the
Administration may permit machinery spaces containing internal combustion
machinery not being main propulsion machinery having an output greater
than 375 kW to be located forward of the cargo area provided the arrangements
are in accordance with the provisions of this paragraph.
5.1.4 In combination carriers only:
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.1 The slop tanks shall be surrounded by cofferdams
except where the boundaries of the slop tanks, where slop may be carried
on dry cargo voyages, are part of the hull, main cargo deck, cargo
pump-room bulkhead or oil fuel bunker tank. These cofferdams shall
not be open to a double bottom, pipe tunnel, pump-room or other enclosed
space, nor shall they be used for cargo or ballast and shall not be
connected to piping systems serving oil cargo or ballast. Means shall
be provided for filling the cofferdams with water and for draining
them. Where the boundary of a slop tank is part of the cargo pump-room
bulkhead, the pump-room shall not be open to the double bottom, pipe
tunnel or other enclosed space; however, openings provided with gastight
bolted covers may be permitted;
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.2 Means shall be provided for isolating the piping
connecting the pump-room with the slop tanks referred to in paragraph
5.1.4.1. The means of isolation shall consist of a valve followed
by a spectacle flange or a spool piece with appropriate blank flanges.
This arrangement shall be located adjacent to the slop tanks, but
where this is unreasonable or impracticable, it may be located within
the pump-room directly after the piping penetrates the bulkhead. A
separate permanently installed pumping and piping arrangement incorporating
a manifold, provided with a shut-off valve and a blank flange, shall
be provided for discharging the contents of the slop tanks directly
to the open deck for disposal to shore reception facilities when the
ship is in the dry cargo mode. When the transfer system is used for
slop transfer in the dry cargo mode, it shall have no connection to
other systems. Separation from other systems by means of removal of
spool pieces may be accepted;
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.3 Hatches and tank cleaning openings to slop
tanks shall only be permitted on the open deck and shall be fitted
with closing arrangements. Except where they consist of bolted plates
with bolts at watertight spacing, these closing arrangements shall
be provided with locking arrangements under the control of the responsible
ship’s officer; and
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.4 Where cargo wing tanks are provided, cargo
oil lines below deck shall be installed inside these tanks. However,
the Administration may permit cargo oil lines to be placed in special
ducts provided there are capable of being adequately cleaned and ventilated
to the satisfaction of the Administration. Where cargo wing tanks
are not provided, cargo oil lines below deck shall be placed in special
ducts.
5.1.5 Where the fitting of a navigation position
above the cargo area is shown to be necessary, it shall be for navigation
purposes only and it shall be separated from the cargo tank deck by
means of an open space with a height of at least 2 m. The fire protection
requirements for such a navigation position shall be that required
for control stations, as specified in regulation 9.2.4.2 and other
provisions for tankers, as applicable.
5.1.6 Means shall be provided to keep deck spills
away from the accommodation and service areas. This may be accomplished
by provision of a permanent continuous coaming of a height of at least
300 mm, extending from side to side. Special consideration shall be
given to the arrangements associated with stern loading.
5.2
Restriction on boundary openings
5.2.1 Except as permitted in paragraph 5.2.2,
access doors, air inlets and openings to accommodation spaces, service
spaces, control stations and machinery spaces shall not face the cargo
area. They shall be located on the transverse bulkhead not facing
the cargo area or on the outboard side of the superstructure or deckhouse
at a distance of at least 4% of the length of the ship but not less
than 3 m from the end of the superstructure or deckhouse facing the
cargo area. This distance need not exceed 5 m.
5.2.2 The Administration may permit access doors
in boundary bulkheads facing the cargo area or within the 5 m limits
specified in paragraph 5.2.1, to main cargo control stations and to
such service spaces used as provision rooms, store-rooms and lockers,
provided they do not give access directly or indirectly to any other
space containing or providing for accommodation, control stations
or service spaces such as galleys, pantries or workshops, or similar
spaces containing sources of vapour ignition. The boundary of such
a space shall be insulated to "A-60" standard, with the exception
of the boundary facing the cargo area. Bolted plates for the removal
of machinery may be fitted within the limits specified in paragraph
5.2.1. Wheelhouse doors and windows may be located within the limits
specified in paragraph 5.2.1 so long as they are designed to ensure
that the wheelhouse can be made rapidly and efficiently gas and vapour
tight.
5.2.3 Windows and sidescuttles facing the cargo
area and on the sides of the superstructures and deckhouses within
the limits specified in paragraph 5.2.1 shall be of the fixed (non-opening)
type. Such windows and sidescuttles, except wheelhouse windows, shall
be constructed to "A-60" class standard.
5.2.4 Where there is permanent access from a pipe
tunnel to the main pump-room, a watertight door shall be fitted complying
with the requirements of regulation
II-1/25-9.2 and, in addition, with the following:
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.1 in addition to the bridge operation, the watertight
door shall be capable of being manually closed from outside the main
pump-room entrance; and
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.2 the watertight door shall be kept closed during
normal operations of the ship except when access to the pipe tunnel
is required.
5.2.5 Permanent approved gastight lighting enclosures
for illuminating cargo pump-rooms may be permitted in bulkheads and
decks separating cargo pump-rooms and other spaces provided they are
of adequate strength and the integrity and gastightness of the bulkhead
or deck is maintained.
5.2.6 The arrangement of ventilation inlets and
outlets and other deckhouse and superstructure boundary space openings
shall be such as to complement the provisions of paragraph 5.3 and
regulation 11.6. Such vents, especially for machinery spaces, shall
be situated as far aft as practicable. Due consideration in this regard
shall be given when the ship is equipped to load or discharge at the
stern. Sources of ignition such as electrical equipment shall be so
arranged as to avoid an explosion hazard.
5.3
Cargo tank venting
5.3.1
General requirements
The venting systems of cargo tanks are to be entirely distinct
from the air pipes of the other compartments of the ship. The arrangements
and position of openings in the cargo tank deck from which emission
of flammable vapours can occur shall be such as to minimize the possibility
of flammable vapours being admitted to enclosed spaces containing
a source of ignition, or collecting in the vicinity of deck machinery
and equipment which may constitute an ignition hazard. In accordance
with this general principle, the criteria in paragraphs 5.3.2 to 5.3.5
and regulation 11.6 will apply.
5.3.2 Venting arrangements
5.3.2.1 The venting arrangements in each cargo
tank may be independent or combined with other cargo tanks and may
be incorporated into the inert gas piping.
5.3.2.2 Where the arrangements are combined with
other cargo tanks, either stop valves or other acceptable means shall
be provided to isolate each cargo tank. Where stop valves are fitted,
they shall be provided with locking arrangements which shall be under
the control of the responsible ship's officer. There shall be a clear
visual indication of the operational status of the valves or other
acceptable means. Where tanks have been isolated, it shall be ensured
that relevant isolating valves are opened before cargo loading or
ballasting or discharging of those tanks is commenced. Any isolation
must continue to permit the flow caused by thermal variations in a
cargo tank in accordance with regulation 11.6.1.1.
5.3.2.3 If cargo loading and ballasting or discharging
of a cargo tank or cargo tank group is intended, which is isolated
from a common venting system, that cargo tank or cargo tank group
shall be fitted with a means for over-pressure or under-pressure protection
as required in regulation 11.6.3.2.
5.3.2.4 The venting arrangements shall be connected
to the top of each cargo tank and shall be self-draining to the cargo
tanks under all normal conditions of trim and list of the ship. Where
it may not be possible to provide self-draining lines, permanent arrangements
shall be provided to drain the vent lines to a cargo tank.
5.3.3
Safety devices in venting systems
The venting system shall be provided with devices to prevent
the passage of flame into the cargo tanks. The design, testing and
locating of these devices shall comply with the requirements established
by the Administration based on the guidelines developed by the Organization.footnote Ullage openings shall not be used for pressure
equalization. They shall be provided with self-closing and tightly
sealing covers. Flame arresters and screens are not permitted in these
openings.
5.3.4
Vent outlets for cargo handling and
ballasting
5.3.4.1 Vent outlets for cargo loading, discharging
and ballasting required by regulation 11.6.1.2 shall:
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.1.1 permit the free flow of vapour mixtures;
or
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.1.2 permit the throttling of the discharge of
the vapour mixtures to achieve a velocity of not less than 30 m/s;
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.2 be so arranged that the vapour mixture is discharged
vertically upwards;
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.3 where the method is by free flow of vapour
mixtures, be such that the outlet shall be not less than 6 m above
the cargo tank deck or fore and aft gangway if situated within 4 m
of the gangway and located not less than 10 m measured horizontally
from the nearest air intakes and openings to enclosed spaces containing
a source of ignition and from deck machinery, which may include anchor
windlass and chain locker openings, and equipment which may constitute
an ignition hazard; and
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.4 where the method is by high-velocity discharge,
be located at a height not less than 2 m above the cargo tank deck
and not less than 10 m measured horizontally from the nearest air
intakes and openings to enclosed spaces containing a source of ignition
and from deck machinery, which may include anchor windlass and chain
locker openings, and equipment which may constitute an ignition hazard.
These outlets shall be provided with high velocity devices of an approved
type.
5.3.4.2 The arrangements for the venting of vapours
displaced from the cargo tanks during loading and ballasting shall
comply with paragraph 5.3 and regulation 11.6 and shall consist of
either one or more mast risers, or a number of high-velocity vents.
The inert gas supply main may be used for such venting.
5.3.5
Isolation of slop tanks in combination
carriers
In combination carriers, the arrangements for isolating
slop tanks containing oil or oil residues from other cargo tanks shall
consist of blank flanges which will remain in position at all times
when cargoes other than liquid cargoes referred to in regulation 1.6.1
are carried.
5.4
Ventilation
5.4.1
Ventilation systems in cargo pump-rooms
Cargo pump-rooms shall be mechanically ventilated and discharges
from the exhaust fans shall be led to a safe place on the open deck.
The ventilation of these rooms shall have sufficient capacity to minimize
the possibility of accumulation of flammable vapours. The number of
air changes shall be at least 20 per hour, based upon the gross volume
of the space. The air ducts shall be arranged so that all of the space
is effectively ventilated. The ventilation shall be of the suction
type using fans of the non-sparking type.
5.4.2
Ventilation systems in combination
carriers
In combination carriers, cargo spaces and any enclosed spaces
adjacent to cargo spaces shall be capable of being mechanically ventilated.
The mechanical ventilation may be provided by portable fans. An approved
fixed gas warning system capable of monitoring flammable vapours shall
be provided in cargo pump-rooms, pipe ducts and cofferdams, as referred
to in paragraph 5.1.4, adjacent to slop tanks. Suitable arrangements
shall be made to facilitate measurement of flammable vapours in all
other spaces within the cargo area. Such measurements shall be made
possible from the open deck or easily accessible positions.
5.5
Inert gas systems
5.5.1
Application
5.5.1.1 For tankers of 20,000 tonnes deadweight
and upwards, the protection of the cargo tanks shall be achieved by
a fixed inert gas system in accordance with the requirements of the Fire Safety Systems Code, except that, in lieu of
the above, the Administration, after having given consideration to
the ship’s arrangement and equipment, may accept other fixed
installations if they afford protection equivalent to the above, in
accordance with regulation I/5.
The requirements for alternative fixed installations shall comply
with the requirements in paragraph 5.5.4.
5.5.1.2 Tankers operating with a cargo tank cleaning
procedure using crude oil washing shall be fitted with an inert gas
system complying with the Fire Safety Systems Code and
with fixed tank washing machines.
5.5.1.3 Tankers required to be fitted with inert
gas systems shall comply with the following provisions:
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.1 double hull spaces shall be fitted with suitable
connections for the supply of inert gas;
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.2 where hull spaces are connected to a permanently
fitted inert gas distribution system, means shall be provided to prevent
hydrocarbon gases from the cargo tanks entering the double hull spaces
through the system; and
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.3 where such spaces are not permanently connected
to an inert gas distribution system, appropriate means shall be provided
to allow connection to the inert gas main.
5.5.2
Inert gas systems of chemical tankers
and gas carriers
The requirements for inert gas systems contained in the Fire Safety Systems Code need not be applied to:
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.1 chemical tankers and gas carriers when carrying
cargoes described in regulation 1.6.1, provided that they comply with
the requirements for inert gas systems on chemical tankers established
by the Administration, based on the guidelines developed by the Organization;footnote or
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.2 chemical tankers and gas carriers when carrying
flammable cargoes other than crude oil or petroleum products such
as cargoes listed in chapters 17 and 18 of the International Bulk Chemical Code,
provided that the capacity of tanks used for their carriage does not
exceed 3,000 m3 and the individual nozzle capacities of
tank washing machines do not exceed 17.5 m3/h and the total
combined throughput from the number of machines in use in a cargo
tank at any one time does not exceed 110 m3/h.
5.5.3
General requirements for inert gas
systems
5.5.3.1 The inert gas system shall be capable
of inerting, purging and gas-freeing empty tanks and maintaining the
atmosphere in cargo tanks with the required oxygen content.
5.5.3.2 The inert gas system referred to in paragraph
5.5.3.1 shall be designed, constructed and tested in accordance with
the Fire Safety Systems Code.
5.5.3.3 Tankers fitted with a fixed inert gas
system shall be provided with a closed ullage system.
5.5.4
Requirements for equivalent systems
5.5.4.1 Where an installation equivalent to a
fixed inert gas system is installed, it shall:
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.1 be capable of preventing dangerous accumulations
of explosive mixtures in intact cargo tanks during normal service
throughout the ballast voyage and necessary in-tank operations; and
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.2 be so designed as to minimize the risk of ignition
from the generation of static electricity by the system itself.
5.6
Inerting, purging and gas-freeing
5.6.1 Arrangements for purging and/or gas-freeing
shall be such as to minimize the hazards due to dispersal of flammable
vapours in the atmosphere and to flammable mixtures in a cargo tank.
5.6.2 The procedure for cargo tank purging and/or
gas-freeing shall be carried out in accordance with regulation 16.3.2.
5.6.3 The arrangements for inerting, purging or
gas-freeing of empty tanks as required in paragraph 5.5.3.1 shall
be to the satisfaction of the Administration and shall be such that
the accumulation of hydrocarbon vapours in pockets formed by the internal
structural members in a tank is minimized and that:
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.1 on individual cargo tanks, the gas outlet pipe,
if fitted, shall be positioned as far as practicable from the inert
gas/air inlet and in accordance with paragraph 5.3 and regulation
11.6. The inlet of such outlet pipes may be located either at deck
level or at not more than 1 m above the bottom of the tank;
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.2 the cross-sectional area of such gas outlet
pipe referred to in paragraph 5.6.3.1 shall be such that an exit velocity
of at least 20 m/s can be maintained when any three tanks are being
simultaneously supplied with inert gas. Their outlets shall extend
not less than 2 m above deck level; and
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.3 each gas outlet referred to in paragraph 5.6.3.2
shall be fitted with suitable blanking arrangements.
5.7
Gas measurement
5.7.1
Portable instrument
Tankers shall be equipped with at least one portable instrument
for measuring flammable vapour concentrations, together with a sufficient
set of spares. Suitable means shall be provided for the calibration
of such instruments.
5.7.2
Arrangements for gas measurement in
double hull and double bottom spaces
5.7.2.1 Suitable portable instruments for measuring
oxygen and flammable vapour concentrations shall be provided. In selecting
these instruments, due attention shall be given to their use in combination
with the fixed gas-sampling-line systems referred to in paragraph
5.7.2.2.
5.7.2.2 Where the atmosphere in double hull spaces
cannot be reliably measured using flexible gas sampling hoses, such
spaces shall be fitted with permanent gas sampling lines. The configuration
of gas sampling lines shall be adapted to the design of such spaces.
5.7.2.3 The materials of construction and the
dimensions of gas sampling lines shall be such as to prevent restriction.
Where plastic materials are used, they shall be electrically conductive.
5.8
Air supply to double hull and double
bottom spaces
Double hull and double bottom spaces shall be fitted with
suitable connections for the supply of air.
5.9
Protection of cargo area
Drip pans for collecting cargo residues in cargo lines and
hoses shall be provided in the area of pipe and hose connections under
the manifold area. Cargo hoses and tank washing hoses shall have electrical
continuity over their entire lengths including couplings and flanges
(except shore connections) and shall be earthed for removal of electrostatic
charges.
5.10
Protection of cargo pump-rooms
5.10.1 In tankers:
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.1 cargo pumps, ballast pumps and stripping pumps,
installed in cargo pumprooms and driven by shafts passing through
pump-room bulkheads shall be fitted with temperature sensing devices
for bulkhead shaft glands, bearings and pump casings. A continuous
audible and visual alarm signal shall be automatically effected in
the cargo control room or the pump control station;
-
.2 lighting in cargo pump-rooms, except emergency
lighting, shall be interlocked with ventilation such that the ventilation
shall be in operation when switching on the lighting. Failure of the
ventilation system shall not cause the lighting to go out;
-
.3 a system for continuous monitoring of the concentration
of hydrocarbon gases shall be fitted. Sampling points or detector
heads shall be located in suitable positions in order that potentially
dangerous leakages are readily detected. When the hydrocarbon gas
concentration reaches a pre-set level which shall not be higher than
10% of the lower flammable limit, a continuous audible and visual
alarm signal shall be automatically effected in the pump-room, engine
control room, cargo control room and navigation bridge to alert personnel
to the potential hazard; and
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.4 all pump-rooms shall be provided with bilge
level monitoring devices together with appropriately located alarms.
Regulation 5 – Fire
growth potential
1 Purpose
The purpose of this regulation is to limit the fire growth
potential in every space of the ship. For this purpose, the following
functional requirements shall be met:
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.1 means of control for the air supply to the
space shall be provided;
-
.2 means of control for flammable liquids in the
space shall be provided; and
-
.3 the use of combustible materials shall be restricted.
2 Control of air supply and flammable liquid to
the space
2.1
Closing appliances and stopping devices
of ventilation
2.1.1 The main inlets and outlets of all ventilation
systems shall be capable of being closed from outside the spaces being
ventilated. The means of closing shall be easily accessible as well
as prominently and permanently marked and shall indicate whether the
shut-off is open or closed.
2.1.2 Power ventilation of accommodation spaces,
service spaces, cargo spaces, control stations and machinery spaces
shall be capable of being stopped from an easily accessible position
outside the space being served. This position shall not be readily
cut off in the event of a fire in the spaces served.
2.1.3 In passenger ships carrying more than 36
passengers, power ventilation, except machinery space and cargo space
ventilation and any alternative system which may be required under
regulation 8.2, shall be fitted with controls so grouped that all
fans may be stopped from either of two separate positions which shall
be situated as far apart as practicable. Fans serving power ventilation
systems to cargo spaces shall be capable of being stopped from a safe
position outside such spaces.
2.2
Means of control in machinery spaces
2.2.1 Means of control shall be provided for opening
and closure of skylights, closure of openings in funnels which normally
allow exhaust ventilation and closure of ventilator dampers.
2.2.2 Means of control shall be provided for stopping
ventilating fans. Controls provided for the power ventilation serving
machinery spaces shall be grouped so as to be operable from two positions,
one of which shall be outside such spaces. The means provided for
stopping the power ventilation of the machinery spaces shall be entirely
separate from the means provided for stopping ventilation of other
spaces.
2.2.3 Means of control shall be provided for stopping
forced and induced draught fans, oil fuel transfer pumps, oil fuel
unit pumps, lubricating oil service pumps, thermal oil circulating
pumps and oil separators (purifiers). However, paragraphs 2.2.4 and
2.2.5 need not apply to oily water separators.
2.2.4 The controls required in paragraphs 2.2.1
to 2.2.3 and in regulation 4.2.2.3.4 shall be located outside the
space concerned so they will not be cut off in the event of fire in
the space they serve.
2.2.5 In passenger ships, the controls required
in paragraphs 2.2.1 to 2.2.4 and in regulations 8.3.3 and 9.5.2.3
and the controls for any required fire-extinguishing system shall
be situated at one control position or grouped in as few positions
as possible to the satisfaction of the Administration. Such positions
shall have a safe access from the open deck.
2.3
Additional requirements for means of
control in periodically unattended machinery spaces
2.3.1 For periodically unattended machinery spaces,
the Administration shall give special consideration to maintaining
the fire integrity of the machinery spaces, the location and centralization
of the fire-extinguishing system controls, the required shutdown arrangements
(e.g. ventilation, fuel pumps, etc.) and that additional fire-extinguishing
appliances and other fire-fighting equipment and breathing apparatus
may be required.
2.3.2 In passenger ships, these requirements shall
be at least equivalent to those of machinery spaces normally attended
3 Fire protection materials
3.1
Use of non-combustible materials
3.1.1
Insulating materials
Insulating materials shall be non-combustible, except in
cargo spaces, mail rooms, baggage rooms and refrigerated compartments
of service spaces. Vapour barriers and adhesives used in conjunction
with insulation, as well as the insulation of pipe fittings for cold
service systems, need not be of non-combustible materials, but they
shall be kept to the minimum quantity practicable and their exposed
surfaces shall have low flame-spread characteristics.
3.1.2
Ceilings and linings
3.1.2.1 In passenger ships, except in cargo spaces,
all linings, grounds, draught stops and ceilings shall be of non-combustible
material except in mail rooms, baggage rooms, saunas or refrigerated
compartments of service spaces. Partial bulkheads or decks used to
subdivide a space for utility or artistic treatment shall also be
of non-combustible materials.
3.1.2.2 In cargo ships, all linings, ceilings,
draught stops and their associated grounds shall be of non-combustible
materials in the following spaces:
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.1 in accommodation and service spaces and control
stations for ships where Method IC is specified as referred to in
regulation 9.2.3.1; and
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.2 in corridors and stairway enclosures serving
accommodation and service spaces and control stations for ships where
Method IIC and IIIC are specified as referred to in regulation 9.2.3.1.
3.2
Use of combustible materials
3.2.1
General
3.2.1.1 In passenger ships, “A”, "B"
or "C" class divisions in accommodation and services spaces which
are faced with combustible materials, facings, mouldings, decorations
and veneers shall comply with the provisions of paragraphs 3.2.2 to
3.2.4 and regulation 6. However, traditional wooden benches and wooden
linings on bulkheads and ceilings are permitted in saunas and such
materials need not be subject to the calculations prescribed in paragraphs
3.2.2 and 3.2.3.
3.2.1.2 In cargo ships, non-combustible bulkheads,
ceilings and linings fitted in accommodation and service spaces may
be faced with combustible materials, facings, mouldings, decorations
and veneers provided such spaces are bounded by non-combustible bulkheads,
ceilings and linings in accordance with the provisions of paragraphs
3.2.2 to 3.2.4 and regulation 6.
3.2.2
Maximum calorific value of combustible
materials
Combustible materials used on the surfaces and linings specified
in paragraph 3.2.1 shall have a calorific valuefootnote not exceeding 45 MJ/m2 of the area
for the thickness used. The requirements of this paragraph are not
applicable to the surfaces of furniture fixed to linings or bulkheads.
3.2.3
Total volume of combustible materials
Where combustible materials are used in accordance with
paragraph 3.2.1, they shall comply with the following requirements:
-
.1 The total volume of combustible facings, mouldings,
decorations and veneers in accommodation and service spaces shall
not exceed a volume equivalent to 2.5 mm veneer on the combined area
of the walls and ceiling linings. Furniture fixed to linings, bulkheads
or decks need not be included in the calculation of the total volume
of combustible materials; and
-
.2 In the case of ships fitted with an automatic
sprinkler system complying with the provisions of the Fire
Safety Systems Code, the above volume may include some combustible
material used for erection of "C" class divisions.
3.2.4
Low flame-spread characteristics of
exposed surfaces
3.2.4.1 In passenger ships:
-
.1 exposed surfaces in corridors and stairway
enclosures and of bulkhead and ceiling linings in accommodation and
service spaces (except saunas) and control stations; and
-
.2 surfaces and grounds in concealed or inaccessible
spaces in accommodation and service spaces and control stations.
3.2.4.2 In cargo ships:
-
.1 exposed surfaces in corridors and stairway
enclosures and of ceilings in accommodation and service spaces (except
saunas) and control stations; and
-
.2 surfaces and grounds in concealed or inaccessible
spaces in accommodation and service spaces and control stations.
3.3
Furniture in stairway enclosures of passenger
ships
Furniture in stairway enclosures shall be limited to seating.
It shall be fixed, limited to six seats on each deck in each stairway
enclosure, be of restricted fire risk determined in accordance with
the Fire Test Procedure Code, and shall not
restrict the passenger escape route. The Administration may permit
additional seating in the main reception area within a stairway enclosure
if it is fixed, non-combustible and does not restrict the passenger
escape route. Furniture shall not be permitted in passenger and crew
corridors forming escape routes in cabin areas. In addition to the
above, lockers of non-combustible material, providing storage for
non-hazardous safety equipment required by these regulations, may
be permitted. Drinking water dispensers and ice cube machines may
be permitted in corridors provided they are fixed and do not restrict
the width of the escape routes. This applies as well to decorative
flower or plant arrangements, statues or other objects of art such
as paintings and tapestries in corridors and stairways.
Regulation 6 – Smoke
generation potential and toxicity
1 Purpose
The purpose of this regulation is to reduce the hazard to
life from smoke and toxic products generated during a fire in spaces
where persons normally work or live. For this purpose, the quantity
of smoke and toxic products released from combustible materials, including
surface finishes, during fire shall be limited.
2 Paints, varnishes and other finishes
Paints, varnishes and other finishes used on exposed interior
surfaces shall not be capable of producing excessive quantities of
smoke and toxic products, this being determined in accordance with
the Fire Test Procedures Code.
3 Primary deck coverings
Primary deck coverings, if applied within accommodation
and service spaces and control stations, shall be of approved material
which will not give rise to smoke or toxic or explosive hazards at
elevated temperatures, this being determined in accordance with the Fire Test Procedures Code.
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