Chapter 4 – Useful Arrangement, Installation and Apparatus for Fire Safety
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1321 – Guidelines for Measures to Prevent Fires in Engine-Rooms and Cargo Pump-Rooms – (11 June 2009) - Annex – Guidelines for Measures to Prevent Fire in Engine-Rooms and cargo Pump-Rooms - Part 3 – Engine-Rooms - Chapter 4 – Useful Arrangement, Installation and Apparatus for Fire Safety

Chapter 4 – Useful Arrangement, Installation and Apparatus for Fire Safety

Parent topic: Part 3 – Engine-Rooms

1 Measures for the prevention of spillage of flammable oils

1.1 Tanks

  1.1.1 Tanks used for the storage of fuel oil, lubricating oil, hydraulic oil, thermal oil and other flammable oils, together with their fittings, should be constructed so as to prevent overpressure and spillages due to leakage or overfilling.

  1.1.2 An alarm device should be provided to give warning when the oil reaches a predetermined level in the tank or, alternatively, a sight glass should be provided in the overflow pipe to indicate when any tank is overflowing. Such sight glasses should be placed on vertical pipes only, in readily visible positions, and should be shown by testing to have a suitable degree of fire resistance.

  1.1.3 Any overflow pipe should have a sectional area of at least 1.25 times that of the filling pipe and should be led to an overflow tank of adequate capacity or to a storage tank having space reserved for overflow purposes.

1.2 Air and overflow pipes

  1.2.1 Air pipes from oil fuel tanks and heated lubricating oil tanks should be led to a safe position on the open deck. They should not terminate in any place where a risk of ignition is present. Air pipes from unheated lubricating oil tanks may terminate in the machinery space, provided that the open ends are so situated that issuing oil cannot come into contact with electrical equipment, heated or hot surfaces.

  1.2.2 Any overflow pipe should have a sectional area of at least 1.25 times that of the filling pipe and should be led to an overflow tank of adequate capacity or to a storage tank having space reserved for overflow purposes.

  1.2.3 In order to fulfil the requirements of SOLAS regulation II-1/26.11, a common air pipe is commonly used. In this case the air pipes from heated and unheated oil tanks should be separated.

1.3 Measuring devices of tanks

  1.3.1 Where sounding pipes are used, they should not terminate in any space where the risk of ignition of spillage from the sounding pipe might arise. In particular, they should not terminate in passenger or crew spaces. As a general rule, they should not terminate in machinery spaces. However, where the classification society considers that these latter requirements are impracticable, it may permit termination of sounding pipes from tanks in machinery spaces, on condition that all of the following requirements are met:

  • .1 an oil level gauge of an approved type is provided;

  • .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 from the sounding pipes, coming into contact with a source of ignition; and

  • .3 the terminations 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 purposes of ascertaining before the blanking device is opened that oil fuel is not present. Provision should be made so as to ensure that any spillage of oil fuel through the control cock involves no ignition hazard. Locking arrangements for self-closing blanking devices to be kept in the open position should not be permitted.

  1.3.2 Short sounding pipes may be used for tanks, other than double bottom tanks, without the additional closed level gauge provided an overflow system is fitted.

  1.3.3 Oil level gauges may be used in place of sounding pipes, subject to the following conditions:

  • .1 in passenger ships, such gauges should not require penetration below the top of the tank and their failure or overfilling of the tanks will not permit release of fuel; and

  • .2 in cargo ships, the failure of such gauges or overfilling of the tank should not permit release of fuel. The use of cylindrical gauge glasses is prohibited. The classification society may permit the use of oil-level gauges with flat glasses and self-closing valves between the gauges and fuel tanks.

2 Fuel oil isolation valves for multi-engines

  2.1 In order to fulfil SOLAS regulation II-2/4.2.2.5.5, isolating valves should be located and operable from a position not rendered inaccessible by a fire on any of the engines.

  2.1.1 Where practicable, isolating valves should be located at least 5 m away from engines in any direction. If this is not possible, the operating position of the valves should be protected by an obstruction. Figure 3-8 shows an example of protection by obstructions.

  2.1.2 If the above is impracticable, other means of protection capable of enabling access to the isolating valves in the event of a fire might be acceptable.

  2.1.3 Figure 3-9 shows the possible areas affected by fire and figure 3-10 shows a schematic diagram of a typical isolation valve arrangement.

  2.1.4 Isolating valves controlled remotely could be acceptable. In this case, the operating mechanism should be protected from fire.

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