601 Fire Protection in machinery spaces

1 The Maritime Safety Committee, at its sixty-first session (7 to 11 December 1992), noted an information paper submitted by IACS dealing with requirements for fire protection in machinery spaces for new ships and providing guidance to owners for fire prevention in machinery spaces of ships in service.

2 The Committee, recognizing the importance of enhancing fire safety in machinery spaces for both new and existing ships and taking into account that fire safety depends on the efforts and good practice of all parties involved, agreed to circulate the annexes to the said document by the present MSC Circular.

3 Member Governments are recommended to apply the provision of annex 1 (Fire protection of machinery spaces, new ships) and circulate annex 2 (Guidance to owners for fire prevention in machinery spaces of ships in service), as appropriate.

Annex 1 IACS F35 - Fire protection of machinery spaces Rev. 2 1991

01 Preamble

This unified requirement concerns machinery spaces as defined in Ch.II-2, Reg. 3.20 of the 1981 SOLAS Amendments, i.e.:

'Machinery spaces' are all machinery spaces of Category A as defined in 1981 SOLAS Amendments and all other spaces containing propulsion machinery, boilers, oil fuel units, steam and internal combustion engines, generators and major electrical machinery, oil filling stations, refrigerating, stabilising, ventilation and air conditioning machinery, and similar spaces, and trunks to such spaces.

Spaces which contain oil-fired equipment other than boilers, such as inert gas generators, incinerators, waste disposal units etc. shall be considered as machinery spaces of Category A.

"Oil fuel unit" as defined in SOLAS Amendments includes any equipment used for the preparation and delivery of oil fuel, heated or not, to boilers (including inert gas generators) and engines (including gas turbines) at a pressure of more than 0,18 N/mm**2.

02 Items to be considered for reducing the fire risk

2.1 Measures for the prevention of spillages of oil fuel, lubricating oil, hydraulic oil, thermal oil and other flammable liquids.

2.1.1 Tanks

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

.2 Air pipes from oil fuel tanks shall be led to a safe position on the open deck. They shall not terminate in any place where a risk of ignition is present. Air pipes from lubricating oil storage 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 or heated surfaces.

.3 Any overflow pipe shall have a sectional area of at least 1,25 times that of the filling pipe and shall be led to an overflow tank of adequate capacity or to a storage tank having space reserved for overflow purposes.

An alarm device shall be provided to give warning when the oil reaches a predetermined level in the tank, or alteratively, a sight glass shall be provided in the overflow pipe to indicate when any tank is overflowing. Such sight glasses shall be placed on vertical pipes only.

.4 Safe and efficient means of ascertaining the amount of oil fuel contained in oil fuel tanks shall be provided.

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 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:

- an oil level gauge is provided meeting the requirements of 2.1.1.6.

- 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 sounding pipes from corning into contact with a source of ignition;

- 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 must be made so as to ensure that any spillage of oil fuel through the control cock involves no ignition hazard;

.5 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.

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

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

- in cargo ships, the failure of such gauges or overfilling of the tank shall not permit release of fuel. The use of cylindrical gauge glasses is prohibited. The Society may permit the use of oil-level gauges with flat glasses and self-closing valves between the gauges and fuel tanks. 2.1.2 Control of pumps

The power supply to all independently-driven oil fuel transfer pumps, oil fuel unit pumps and all other fuel pumps shall be capable of being stopped from a position outside the space that will always be accessible in the event of fire occurring in the compartment in which they are situated, as well as from the compartment itself.

2.1.3 Distribution piping for flammable liquids

.1 Pipes, their joints and fittings shall comply with Unified Requirements P1 and P2.

Short lengths of flexible pipe may be permitted in positions where the Society is satisfied that they are necessary. 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 Society. Hose clamps and similar types of attachments for flexible pipes are not permitted.
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_{*) "The flexible pipe with end attachments shall be subjected to a fire for 30 minutes at a temperature of 800 degrees C, while water at the maximum service pressure is circulated inside the pipe. The temperature of the water at the outlets shall not be less than 80 degrees C. No leak should be recorded during or after the test."}

.2 Every oil fuel pipe, which, if damaged, would allow oil to escape from a storage, settling or daily service tank 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 fitted as close as possible to the penetration of the pipe into the machinery space, and it shall be operated locally and from a position outside this space.

.3 Pipes conveying oil fuel heated above 60 degrees C shall be placed in sight above the platform in well lighted parts of machinery spaces, and the number of flanged joints shall be kept to a minimum necessary for mounting purposes.

The scantlings of the pipes which convey heated oil fuel, as well as their flanges, shall be suitable for a pressure of at least 14 bar or for the design pressure, whichever is greater.

.4 The oil fuel injection and return piping for internal combustion engines shall comply with Unified Requirement M17. Cocks or valves shall be provided for isolating instruments from the main pipes. Temperature sensors shall be fitted in pockets.

.5 All valves and cocks forming part of the oil fuel installation shall be capable of being operated from readily accessible positions.

The number of detachable pipe connections shall be limited to those which are necessary for mounting and dismantling purposes. 2.1.4 Leakage containment arrangements for engines, equipment and boilers

.1 Containment provided for areas where frequent leakage may be expected such as oil burners, purifiers, drains and valves under daily service tanks etc. shall be fitted with adequate drainage. Where drain pipes are provided from collected leakages, they shall be led to a suitable oil drain tank not forming part of an overflow system.

.2 Where boilers are located in machinery spaces on 'tween decks and the boiler rooms are not separated from the machinery space by watertight bulkheads, the 'tween decks shall be provided with coamings at least 200 mm in height. This area may be drained to the bilges.

The drain tank is not to form part of an overflow system. 2.1.5 Valve for oil fuel pumps

Stop valves or cocks shall be fitted on both suction and delivery sides of oil fuel pumps. All oil fuel pumps shall be provided with pressure relief valves on the discharge side so that the discharged oil may be led to the suction side of the pump.

Pressure relief valves need not be fitted when the system is served only by centrifugal pumps, so designed that the pressure delivered cannot exceed that for which the piping is designed.

2.2 Overheating and seizure

2.2.1. Oil heaters

.1 Where steam heaters or heaters using other heating media are provided in fuel or lubricating oil systems, they shall be fitted with at least a high temperature alarm or low flow alarm in addition to a temperature control, except where the temperature dangerous for the ignition of the medium cannot be reached.

.2 When electric heaters are fitted, means shall be provided to ensure that heating elements are permanently submerged during operation.

In order to avoid in any case a surface temperature of heating element of 220 degrees C and above, a safety temperature switch, independent from the automatic control sensor, shall be provided. The safety switch should cut off the electrical power supply in the event of excessive temperature and shall be provided with manual reset.

2.3 Flash point of oil fuel

.1 Oil fuels with a flash point of less than 60 degrees C (closed cup) are not permitted, except for the following:

- ships certified for restricted service within areas having a climate ensuring that ambient temperatures of spaces where such fuel oil is stored will not rise to within 10 degrees C below its flash point, may use oil fuel with flash point below 60 degrees C but not less than 43 degrees C;

- installations complying with UR M24 regarding use of crude oil as fuel;

- in emergency generators oil fuel with a flash point of not less than 43 degrees C may be used. .2 Oil fuel in storage tanks shall not be heated to temperatures within 10 degrees C below the flash point of the fuel oil, except for the following:

- Oil fuel in service tanks, settling tanks and any other tanks in the supply system may be heated above this limit, provided:

* the length of the vent pipes from such tanks and/or a cooling device is sufficient for cooling the vapours to at least 10 degrees C below the flash point of the fuel oil;

* a temperature sensor is fitted in the vent pipe and adjusted to give alarm if the temperature should exceed a limit set at 10 degrees C below the flash point of the fuel;

* the vent pipes are fitted with flare screens meeting the requirements of IMO's Standards for Devices for Preventing Passage of Flames into Cargo Tanks";

* there are no openings from the vapour space of the fuel tanks into machinery spaces (bolted manholes are acceptable);

* enclosed spaces shall not be located directly over such fuel tanks, except for well ventilated cofferdams;

* electrical equipment shall not be fitted in the vapour space of the tanks, unless it is certified to be intrinsically safe.

2.4 Hot surfaces

.1 All surfaces of machinery with high temperatures above 220 degrees C e.g. steam, thermal oil and exhaust gas lines, silencers, exhaust gas boilers, turbo blowers, etc., shall be effectively insulated with non-combustible material to prevent the ignition of combustible materials coming into contact with them. Where the insulation used for this purpose is oil absorbent or may permit the penetration of oil, the insulation shall be encased in steel sheathing or equivalent material.

.2 Boilers shall be suitably insulated with non-combustible material and sheathed with steel or other non-combustible material. The clearance spaces between the boilers and tops of the double bottom tanks, and between the boilers and the sides of the storage tanks in which oil fuel and cargo oil is carried, shall be adequate for the free circulation of the air necessary to keep the temperature of the stored oil sufficiently below its flash point, except in the case of tanks complying with Section 2.3.2.

.3 The insulation shall be of a type and so supported that it will not crack or deteriorate when subject to vibration.

2.5 Oil spillages coming into contact with hot surfaces, electrical installations or other sources of ignition

.1 Precautions (e.g. shielding) shall be taken to prevent oil that may escape under pressure from any pump, filter or heater or piping from coming into contact with sources of ignition.

.2 Oil tanks, pipes, filters, heaters etc. shall not be located immediately above or near units of high temperature including boilers, steam pipe lines, exhaust manifolds, silencers or other equipment required to be insulated, and electrical equipment and, as far as practicable, are to be arranged far apart therefrom. In particular, fuel oil filters under pressure for diesel engines shall be located such that in the event of leakage oil cannot be sprayed onto the exhaust manifold.

.3 Oil filters fitted in parallel for the purpose of enabling cleaning without disrupting oil supply to engines (e.g. duplex filters) are to be provided with arrangements that will minimize the possibility of a filter under pressure being opened by mistake. Filters/filter chambers shall be provided with suitable means for:
- venting when put in operation
- depressurizing before being opened.

Valves or cocks with drain pipes led to a safe location shall be used for this purpose.

.4 Hydraulic units with working pressure above 15 bar shall preferably be placed in separate spaces. If it is impracticable to locate such units in a separate space, adequate shielding shall be provided.

2.6 Faults in boiler firing, scavenging manifold, boiler uptakes and exhaust gas uptakes

2.6.1 Boiler firing

.1 The oil burners shall be so arranged that they cannot be withdrawn unless the oil supply to the burners is cut off.

.2 The fuel supply to all burners shall be capable of being automatically cut off in case of total lack of flame in the combustion chamber; moreover, this shall be warned by a visual and audible alarm. The alarms need not be fitted for domestic boilers.

03 Thermal oil installations

3.1 System arrangements

.1 The inlet and outlet valves of oil-fired thermal oil heaters and exhaust-fired thermal oil heaters shall be controllable from outside the compartment where they are situated. As an alternative, an arrangement for quick gravity drainage of the thermal oil contained in the system into a collecting tank is acceptable.

.2 Heating of liquid cargoes with flash points below 60 degrees C shall be arranged by means of a separate secondary system, located completely within the cargo area.

However, a single circuit system may be accepted on the following conditions:

- system is so arranged that a positive pressure in the coil shall be at least 3 m water column above the static head of the cargo when circulating pump is not in operation,

- the thermal oil system expansion tank shall be fitted with high and low level alarms,

- means shall be provided in the thermal oil system expansion tank for detection of flammable cargo vapours. Portable equipment may be accepted.

- valves for the individual heating coils shall be provided with locking arrangement to ensure that the coils are under static pressure at all times.
.3 The thermal oil circulating pumps shall be arranged for emergency stopping from a position outside the space where they are situated.

.4 Vents from expansion tanks and thermal oil storage tanks of thermal oil heating plants shall be led to open deck.

3.2 Exhaust-fired thermal oil heaters.

.1 The heater shall be so designed and installed that all tubes may easily and readily be inspected for signs of corrosion and leakage.

.2 Visual inspection and tightness testing of the heater tubes to not less than the working pressure shall he carried out annually, and hydraulic testing shall be carried out bi-annually.

.3 The heater shall be fitted with temperature sensor(s) and an alarm for fire detection.

.4 A fixed fire extinguishing and cooling system shall be fitted. A drenching system providing copious amounts of water may be accepted. The exhaust ducting below the exhaust boiler shall be arranged for adequate collection and drainage, to prevent water flowing into the diesel engine. The drain shall be led to a suitable location.

04 Fire detection system

For machinery spaces which are provided with a centralised or automatic control and monitoring system, a fire detection and alarm system is required complying with UR F32.

05 Machinery space arrangement

5.1 Machinery space arrangement

.1 The arrangement of machinery spaces shall be so that safe storage and handling of flammable liquids is ensured.

.2 Heating of liquid cargoes with flash points below 60 degrees C shall be arranged by means of a separate secondary system, located completely within the cargo area.

However, a single circuit system may be accepted on the following conditions:
- system is so arranged that a positive pressure in the coil shall be at least 3 m water column above the static head of the cargo when circulating pump is not in operation,

- the thermal oil system expansion tank shall be fitted with high and low level alarms,

- means shall be provided in the thermal oil system expansion tank for detection of flammable cargo vapours. Portable equipment may be accepted.

- valves for the individual heating coils shall be provided with locking arrangement to ensure that the coils are under static pressure at all times.

.3 The thermal oil circulating pumps shall be arranged for emergency stopping from a position outside the space where they are situated.

.4 Vents from expansion tanks and thermal oil storage tanks of thermal oil heating plants shall be led to open deck. 5.2 Segregation of high risk components

.1 Systems (such as purifiers) for preparing flammable liquid for use in boilers and machinery are subject to the following additional requirements.

.2 The main components in such systems shall be placed in a separate room, enclosed by steel bulkheads extending from deck to deck and provided with self-closing steel doors.

.3 Rooms in which flammable liquids are handled as specified in 5.2.1 shall be provided with:

.1 independent mechanical ventilation or a ventilation arrangement which can be isolated from the machinery space ventilation

.2 fire detecting system

.3 fixed fire extinguishing installation. The extinguishing installation shall be capable of being activated from outside the room.
Closing of ventilation openings shall be effected from a position close to where the extinguishing system is activated.

The extinguishing system shall be separate for the room, but may be a part of the main fire extinguishing system for the machinery space.

.4 If it is impracticable to locate the main components of such systems in a separate space, special consideration shall be given with regard to location, containment of possible leakages, and shielding of the components.

06 Local fixed fire extinguishing systems for areas presenting high fire risk

6.1 A local fixed fire-extinguishing system shall be provided to the satisfaction of the Society for:

.1 Separated oil systems referred to in section 5.2 which, for practical reasons, cannot be located in a separated room;

.2 Fuel installations which are not promptly accessible (e.g. the burner area of top fired boilers, auxiliary boilers on platforms or decks, etc.);

.3 Other areas of high fire risk. 6.2 The system shall be capable of being automatically activated or activated remote manually from the machinery control position or other suitable locations.

Annex 2 IACS No. 18 - Fire Prevention in Machinery Spaces of Ships in Service. - Guidance to Owners.

1. Introduction

1.1 Based on past experience it is known that the combination of combustible materials and sources of ignition are the main cause of machinery space fires. The combustible material involved is in the majority of cases oil, i.e. fuel oil, lubricating oil, thermal oil or hydraulic oil. However, plastic materials in electrical installations may also be combustible material causing outbreak of fires.

1.2 There is a large variety of potential ignition sources and the most common are hot surfaces, e.g. exhaust pipes and steam pipes, over-heating of machinery or ignition from electrical installations due to short circuiting or sparks caused by operation of switchgear. Other frequent ignition sources are those associated with human activities, e.g. smoking, welding and grinding.

1.3 The experiences of classification societies confirm the importance of machinery space fire prevention and the reports of survey - class surveys as well as Safety Equipment Surveys contain frequent references to lack of maintenance of fire safety of machinery spaces.

1.4 Where there is any doubt in applying this Guideline, clarification should be obtained from the individual classification society. Attention is directed to the separate published Rules of each. This Guideline is not meant as a substitute for the society's Rules or the independent judgement and experience of Owners and Surveyors.

2. Contributing Factors to Machinery Space Fires

2.1 Failures resulting from the daily use of machinery space installations, such as e.g. oil leakages, breakage of flexible pipes.

2.2 Lack of adequate cleanliness adds to the fire hazard in two ways.

a) In the first place the probability of occurrence of fire, in particular due to ignition caused by human activities is increased because of the widespread presence of the combustible material in the form of oil spill/oily deposits.

b) Secondly, an unclean machinery space may cause a small fire to spread, e.g. a fire in an electrical switchboard or panel may develop into a full machinery space fire due to the presence of oil spills/oily deposits.

3. Measures to Reduce the Fire Risk

3.1 The classification requirements for the construction and inspection of machinery spaces cannot, alone, ensure the fire safety at all times; the effort of all parties concerned is necessary.

3.2 The Shipowners and their crews should apply a programme of maintenance and housekeeping.

3.3 Where leakage of flammable liquids occurs during normal service or routine maintenance work, special arrangement and early clean-up should be made by the crew to prevent these fluids from reaching other parts of the machinery where danger of ignition may arise.

4. What is IACS Doing?

4.1 At the occasion of the Class Annual Survey a machinery and electrical plant survey is carried out as prescribed in Regulation 10 of the Protocol of 1978 relating to the International Convention for the Safety of Life at Sea, 1974.

4.2 The periodic surveys should mainly ensure that the standard to which the installation was originally built is maintained.

4.3 The Surveyor can only assess the actual condition of the machinery space fittings at the time of survey. In between two inspections the proper maintenance must remain the owner's responsibility.

4.4 A unified requirement has been prepared and approved by the Council of the Association during their May 1986 Meeting. This Unified Requirement "Fire Protection of Machinery Spaces (New Ships)" is enclosed for reference. (Annex 1 to MSC/Circ.601)

5. Defects to Machinery Space Installations

5.1 This part deals with various types of defects found in machinery spaces, which for the most part are caused by a lack of proper maintenance or by improper operation.

5.2 Shielding of high pressure fuel oil pipes

Typical defects found may be of the following nature:

- Partially lacking or damaged shielding.

- Loose or defective end attachments of shielding.

- Flexible pipes used for shielding fitted in such a way that contact between high pressure fuel pipe and flexible pipe causes wear damage.

- Defective drainage arrangements.

5.3 Insulation of Exhaust Pipes, Thermal Oil Pipes and Steam Pipes. Commonly found defects are:

- Partially lacking insulation, typically in way of flanges or at locations where removal of insulation is necessary for maintenance.

- Oil soaked insulation due to damage or the lack of steel sheeting.

The standard of insulation and protection against oil penetration into the insulation is an area where the general standard has improved over the years. In earlier days it was not uncommon for flanges to be left uninsulated and that metal sheeting of the insulation was incomplete. In cases where incomplete insulation or unsheeted insulation is found in locations where oil leakages may occur, the owner and operating personnel should make improvements regardless of the original standard.

5.4 Shielding of electrical equipment against oil and water leakages

Oil leakages into electrical equipment may be ignited due to sparks normally generated by penetration of switchgear (fine oil spray is probably most susceptible to ignition). Water leakages may cause short circuiting and ignition of insulation or other material of plastic type. The owner and operating personnel should in particular look for signs of leaking flanges, deterioration of pipes and leakages from other machinery which may come into contact with subject electrical equipment.

6. Crew's and Owner's Duties with Respect to Machinery Space Installations

6.1 Attention should be directed at the condition of flexible pipes used in oil systems, e.g. in connection with hydraulic power arrangements, flexible pipes are used to prevent harmful vibrations and noise. High pressures in combination with pulsations may cause breakage of the flexible pipes, particularly in way of end attachments.

6.2 Also, flexible pipes for connecting fuel oil supply to oil burners are extensively used. Any signs of deteriorating conditions being revealed, should be replaced or at least temporarily repaired.

6.3 Broken or loose fastenings of oil pipes should be repaired because they may result in future damage.

6.4 It is Owner's responsibility to ensure that the machinery space is maintained in a clean condition.

A cleanliness level is not acceptable in cases where floor plates are slippery from extensive oil spills or oil is seeping from machinery or if painted surfaces have an oil layer, or when a fire hazard exists due, for instance, to accumulation of rags or other similar materials or presence of oil on bilge water surface.

• Informatietype: Internationaal
• Documentsoort: Circulaire niet in wetten.nl
• Toegangsrechten: Extern
• Identificatie: PUC_1731_14
• Versie: 1
• Datum beschikbaarheid: 07-06-2006
• Geldigheid van: 29-01-1993
• Wijzigingsdatum: 24-11-2016
• Titel: 601 Fire Protection in machinery spaces
• Organisatie: International Maritime Organization (IMO)
• Taal: Nederlands
• Thema: 0600 until 0699