6.2 Probability of Ignition:

Purpose

(1) The purpose of this paragraph is to prevent the ignition of combustible materials or flammable liquids. For this purpose, the following functional requirements shall be met-

• (a) means shall be provided to control leaks of flammable liquids;

• (b) means shall be provided to limit the accumulation of flammable vapours;

• (c) the ignitability of combustible materials shall be restricted;

• (d) ignition sources shall be restricted; and

• (e) ignition sources shall be separated from combustible materials and flammable liquids.

Arrangements for Oil Fuel, Lubrication Oil, other Flammable Oils and Gaseous Fuels

(2) The following limitations shall apply to the use of oil as fuel-

• (a) except as otherwise permitted by this paragraph, no oil fuel with a flashpoint of less than 60°C shall be used;

• (b) in emergency generators, oil fuel with a flashpoint of not less than 43°C may be used;

• (c) 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-

  • (i) fuel oil tanks except those arranged in double bottom compartments shall be located outside of machinery spaces of category A;

  • (ii) provisions for the measurement of oil temperature are provided on the suction pipe of the oil fuel pump;

  • (iii) stop valves and/or cocks are provided on the inlet side and outlet side of the oil fuel strainers; and

  • (iv) pipe joints of welded construction or of circular cone type or spherical type union joint are applied as much as possible.

(3) 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 subsections (4) through (22) inclusive.

(4) 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 and the machinery spaces in way of such parts of the oil fuel system shall be adequately illuminated.

(5) The ventilation of machinery spaces shall be sufficient under normal conditions to prevent accumulation of oil vapour.

(6) Fuel oil, lubrication oil and other flammable oils shall not be carried in forepeak tanks.

(7) The following provisions shall apply to the structure and location of oil fuel tanks-

• (a) as far as practicable, oil fuel tanks shall be part of the ship's structure and shall be located outside machinery spaces of category A;

• (b) 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; and

• (c) where 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. The use of free-standing oil fuel tanks shall be prohibited in category A machinery spaces.

(8) No oil fuel tank shall be situated where spillage or leakage therefrom can constitute a fire or explosion hazard by falling on heated surfaces.

(9) Oil fuel pipes, which, if damaged, would allow oil to escape from a storage, settling or daily service tank having a capacity of 500 litres and above situated above the double bottom, shall be provided with a remote means of closing as follows-

• (a) subject to paragraph (b) the tank 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;

• (b) in the special case of deep tanks situated in any shaft or pipe tunnel or similar space, whilst valves on the tank shall be fitted, 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, provided that if such an additional valve is fitted in the machinery space, it shall be operated from a position outside that space;

• (c) 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.

(10) Safe and efficient means of ascertaining the amount of oil fuel contained in any oil fuel tank shall be provided.

(11) Where sounding pipes are used-

• (a) they shall not terminate in any space where the risk of ignition of spillage from the sounding pipe might arise and in particular, they shall not terminate in passenger or crew spaces; and

• (b) as a general rule they shall not terminate in machinery spaces provided that where the Administration considers that this requirement is impracticable, it may permit termination of sounding pipes in machinery spaces on condition that all of the following requirements are met-

  • (i) an oil-level gauge is provided meeting the requirements of subsection (12);

  • (ii) 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;

  • (iii) the terminations of the 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; and

  • (iv) provisions are made so as to ensure that any spillage of oil fuel through the control cock involves no ignition hazard.

(12) Other oil-level gauges may be used in place of sounding pipes provided 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.

(13) The means prescribed in subsection (12) which are acceptable to the Administration shall be maintained in the proper condition to ensure their continued accurate functioning in service.

(14) Provisions shall be made to-

• (a) prevent overpressure in any oil tank or in any part of the oil fuel system, including the filling pipes served by pumps on board; and

• (b) to ensure that 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 such pipes shall not lead into crew, machinery, passenger or similar spaces.

(15) Oil fuel pipes and their valves and fittings shall conform to the following requirements-

• (a) they shall be of steel or other approved material provided that, subject to paragraph (b), restricted use of flexible pipes shall be permissible in positions where the Administration is satisfied that they are necessary;

• (b) flexible pipes permitted under paragraph (a), and their end attachments, shall be of approved fire-resisting materials of adequate strength and shall be constructed to the satisfaction of the Administration; and

• (c) where valves fitted to oil fuel tanks are subject to static pressure, steel or spheroidal-graphite cast iron may be accepted provided that 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.

(16) External high-pressure fuel delivery lines between the high-pressure fuel pumps and fuel injectors shall be protected with a jacketed piping system which-

• (a) shall incorporate an outer pipe into which the high-pressure fuel pipe is placed, forming a permanent assembly;

• (b) shall be capable of containing fuel from a high-pressure line failure; and

• (c) shall include a means for collection of leakages and be provided with an alarm in case of a fuel line failure.

(17) Oil fuel lines shall-

• (a) not be located immediately above or near units of high temperature, including boilers, steam pipelines, exhaust manifolds, silencers or other equipment required to be protected by subsections (21) and (22);

• (b) as far as practicable, be arranged so as to be far apart from hot surfaces, electrical installations or other sources of ignition;

• (c) be screened or otherwise suitably protected to avoid oil spray or oil leakage onto the sources of ignition; and

• (d) be arranged such that the number of joints in such piping systems shall be kept to a minimum.

(18) 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 and 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.

(19) 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 and such 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.

(20) 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.

(21) Surfaces with temperatures above 220°C which may be impinged as a result of a fuel system failure shall be properly insulated.

(22) 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.

(23) The arrangements for the storage, distribution and utilisation of oil used in pressure lubrication systems shall be such as to ensure the safety of the ship and persons on board and the arrangements made in machinery spaces of category A, and whenever practicable in other machinery spaces, shall at least comply with the provisions of subsections (7) to 10, (14), (15), (17), (21) and (22), provided that-

• (a) 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

• (b) sounding pipes may be authorised in machinery spaces and the requirements of subsections (11)(b)(i) and (11)(b)(iii) need not be applied provided that that the sounding pipes are fitted with appropriate means of closure.

(24) The provisions of subsection (9) shall also apply to lubricating oil tanks having a capacity of 500 litres or more, 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.

(25) The arrangements for the storage, distribution and utilisation of other flammable oils employed under pressure in power transmission systems, control and activating systems and heating systems shall-

• (a) be such as to ensure the safety of the ship and persons on board;

• (b) shall be fitted with suitable oil collecting arrangements for leaks below hydraulic valves and cylinders;

• (c) where means of ignition are present, at least comply with the provisions of subsections (8), (10), (13), (21), and (22), and with the provisions of subsections (14) and (15) in respect of strength and construction.

(26) The arrangements for the storage, distribution and utilisation of fuels having a flashpoint of less than 60°C for use in vehicles and pleasure craft shall be such as to ensure the safety of the ship and persons on board and such arrangements shall at least comply with the provisions of section 6.16(10) and section 8 of Annex 2 (Technical Standards for Helicopter Landing Areas and Helicopter Operating Standards).

(27) In addition to the requirements of subsections (2) to (4), the oil fuel and lubricating oil systems in a periodically unattended machinery space shall comply with the following-

• (a) 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

• (b) 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.

(28) Where gaseous fuel is used for domestic purposes, the arrangements for the storage, distribution and utilisation of the fuel are to be such that, having regard to the hazards of fire and explosion which the use of the fuel may entail, the safety of the ship and the persons on board is preserved and the installation is to be in accordance with recognised national or international standards acceptable to the Administration.

(29) Storage lockers for gas cylinders are to be provided with-

• (a) effective ventilation;

• (b) an outward-opening door accessible directly to the open deck;

• (c) gas-tight boundaries, including doors and other means of closing any openings therein, which form boundaries between such lockers and adjoining spaces; and

• (d) equipment and fittings which are to be certified as safe for the environment in which they are being used,

(30) Spaces using gaseous fuel for heating, cooking or other purposes shall be provided with an effective power ventilation system which shall be in operation at all times when gas is being used in such spaces and means shall be provided on the navigation bridge to indicate any loss of the required ventilating capacity.

Miscellaneous Items of Ignition Sources and Ignitability

(31) Electric radiators, if used, shall be fixed in position and so constructed as to reduce fire risks to a minimum and 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.

(32) Waste receptacles shall be constructed of non-combustible materials with no openings in the sides or bottom subject to the following-

• (a) plastic bins in galleys are for food waste only and should be clearly marked in accordance with vessels Garbage Management Plan;

• (b) plastic bins in galleys used for Glass and Tins only should be suitably marked in accordance with the Garbage Management Plan and kept clear from any heat source; and

• (c) fire retardant fibreglass bins are acceptable for general waste around the ship provided they are fitted with metal liners.

(33) In spaces where penetration of oil products is possible, the surface of insulation shall be impervious to oil or oil vapours.

(34) Notwithstanding 6.4(4) & (5) primary deck coverings, if applied within accommodation and service spaces, control stations, and cabin balconies shall be of approved material which will not readily ignite, this being determined in accordance with the Fire Test Procedures Code.