Regulation 3 - Definitions
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Regulation 3 - Definitions

 For the purpose of this chapter, unless expressly provided otherwise, the following definitions shall apply:

  1 Accommodation spaces are those spaces used for public spaces, corridors, lavatories, cabins, offices, hospitals, cinemas, game and hobby rooms, barber shops, pantries containing no cooking appliances and similar spaces;

  2 "A" class divisions are those divisions formed by bulkheads and decks which comply with the following criteria:

  • .1 they are constructed of steel or other equivalent material;

  • .2 they are suitably stiffened;

  • .3 they are insulated with approved non-combustible materials such that the average temperature of the unexposed side will not rise more than 140°C above the original temperature, nor will the temperature, at any one point, including any joint, rise more than 180°C above the original temperature, within the time listed below:

class "A-60" 60 min
class "A-30" 30 min
class "A-15" 15 min
class "A-0" 0 min
  • .4 they are constructed as to be capable of preventing the passage of smoke and flame to the end of the one-hour standard fire test; and

  • .5 the Administration required a test of a prototype bulkhead or deck in accordance with the Fire Test Procedures Code to ensure that it meets the above requirements for integrity and temperature rise.

  3 Atriums are public spaces within a single main vertical zone spanning three or more open decks.

  4 "B" class divisions are those divisions formed by bulkheads, decks, ceilings or linings which comply with the following criteria:

  • .1 they are constructed of approved non-combustible materials and all materials used in the construction and erection of "B" class divisions are non-combustible, with the exception that combustible veneers may be permitted provided they meet other appropriate requirements of this chapter;

  • .2 they have an insulation value such that the average temperature of the unexposed side will not rise more than 140°C above the original temperature, nor will the temperature at any one point, including any joint, rise more than 225°C above the original temperature, within the time listed below:

class "B-15" 15 min
class "B-0" 0 min
  • .3 they are constructed as to be capable of preventing the passage of flame to the end of the first half hour of the standard fire test; and

  • .4 the Administration required a test of a prototype division in accordance with the Fire Test Procedures Code to ensure that it meets the above requirements for integrity and temperature rise.

  5 Bulkhead deck is the uppermost deck up to which the transverse watertight bulkheads are carried.

  6 Cargo area is that part of the ship that contains cargo holds, cargo tanks, slop tanks and cargo pump-rooms including pump-rooms, cofferdams, ballast and void spaces adjacent to cargo tanks and also deck areas throughout the entire length and breadth of the part of the ship over the above-mentioned spaces.

  7 Cargo ship is a ship as defined in regulation I/2(g).

  8 Cargo spaces are spaces used for cargo, cargo oil tanks, tanks for other liquid cargo and trunks to such spaces.

  9 Central control station is a control station in which the following control and indicator functions are centralized:

  • .1 fixed fire detection and fire alarm systems;

  • .2 automatic sprinkler, fire detection and fire alarm systems;

  • .3 fire door indicator panels;

  • .4 fire door closure;

  • .5 watertight door indicator panels;

  • .6 watertight door closures;

  • .7 ventilation fans;

  • .8 general/fire alarms;

  • .9 communication systems including telephones; and

  • .10 microphones to public address systems.

  10 "C" class divisions are divisions constructed of approved non-combustible materials. They need meet neither requirements relative to the passage of smoke and flame nor limitations relative to the temperature rise. Combustible veneers are permitted provided they meet the requirements of this chapter.

  11 Chemical tanker is a cargo ship constructed or adapted and used for the carriage in bulk of any liquid product of a flammable nature listed in chapter 17 of the International Bulk Chemical Code, as defined in regulation VII/8.1.

  12 Closed ro-ro spaces are ro-ro spaces which are neither open ro-ro spaces nor weather decks.

  13 Closed vehicle spaces are vehicle spaces which are neither open vehicle spaces nor weather decks

  14 Combination carrier is a cargo ship designed to carry both oil and solid cargoes in bulk.

  15 Combustible material is any material other than a non-combustible material.

  16 Continuous "B" class ceilings or linings are those "B" class ceilings or linings which terminate at an "A" or "B" class division.

  17 Continuously manned central control station is a central control station which is continuously manned by a responsible member of the crew.

  18 Control stations are those spaces in which the ship's radio or main navigating equipment or the emergency source of power is located or where the fire recording or fire control equipment is centralized. Spaces where the fire recording or fire control equipment is centralized are also considered to be a fire control station.

  19 Crude oil is any oil occurring naturally in the earth whether or not treated to render it suitable for transportation and includes crude oil where certain distillate fractions may have been removed from or added to.

  20 Dangerous goods are those goods referred to in the IMDG Code, as defined in regulation VII/1.1.

  21 Deadweight is the difference in tonnes between the displacement of a ship in water of a specific gravity of 1.025 at the load waterline corresponding to the assigned summer freeboard and the lightweight of the ship.

  22 Fire Safety Systems Code means the International Code for Fire Safety Systems as adopted by the Maritime Safety Committee of the Organization by resolution MSC.98(73), as may be amended by the Organization, provided that such amendments are adopted, brought into force and take effect in accordance with the provisions of article VIII of the present Convention concerning the amendment procedures applicable to the annex other than chapter I thereof.

  23 Fire Test Procedures Code means the International Code for Application of Fire Test Procedures, 2010 (2010 FTP Code) as adopted by the Maritime Safety Committee of the Organization by resolution MSC.307(88), as may be amended by the Organization, provided that such amendments are adopted, brought into force and take effect in accordance with the provisions of article VIII of the present Convention concerning the amendment procedures applicable to the Annex other than chapter I.

  24 Flashpoint is the temperature in degrees Celsius (closed cup test) at which a product will give off enough flammable vapour to be ignited, as determined by an approved flashpoint apparatus.

  25 Gas carrier is a cargo ship constructed or adapted and used for the carriage in bulk of any liquefied gas or other products of a flammable nature listed in chapter 19 of the International Gas Carrier Code, as defined in regulation VII/11.1.

  26 Helideck is a purpose-built helicopter landing area located on a ship including all structure, fire-fighting appliances and other equipment necessary for the safe operation of helicopters.

  27 Helicopter facility is a helideck including any refuelling and hangar facilities

  28 Lightweight is the displacement of a ship in tonnes without cargo, fuel, lubricating oil, ballast water, fresh water and feedwater in tanks, consumable stores, and passengers and crew and their effects.

  29 Low flame-spread means that the surface thus described will adequately restrict the spread of flame, this being determined in accordance with the Fire Test Procedures Code.

  30 Machinery spaces are machinery spaces of category A and other spaces containing propulsion machinery, boilers, oil fuel units, steam and internal combustion engines, generators and major electrical machinery, oil filling stations, refrigerating, stabilizing, ventilation and air conditioning machinery, and similar spaces, and trunks to such spaces.

  31 Machinery spaces of category A are those spaces and trunks to such spaces which contain either:

  • .1 internal combustion machinery used for main propulsion;

  • .2 internal combustion machinery used for purposes other than main propulsion where such machinery has in the aggregate a total power output of not less than 375 kW; or

  • .3 any oil-fired boiler or oil fuel unit, or any oil-fired equipment other than boilers, such as inert gas generators, incinerators, etc.

  32 Main vertical zones are those sections into which the hull, superstructure and deckhouses are divided by "A" class divisions, the mean length and width of which on any deck does not in general exceed 40 m.

  33 Non-combustible material is a material which neither burns nor gives off flammable vapours in sufficient quantity for self-ignition when heated to approximately 750°C, this being determined in accordance with the Fire Test Procedures Code.

  34 Oil fuel unit is the equipment used for the preparation of oil fuel for delivery to an oil-fired boiler, or equipment used for the preparation for delivery of heated oil to an internal combustion engine, and includes any oil pressure pumps, filters and heaters dealing with oil at a pressure of more than 0.18 N/mm2.

  35 Open ro-ro spaces are those ro-ro spaces that are either open at both ends or have an opening at one end, and are provided with adequate natural ventilation effective over their entire length through permanent openings distributed in the side plating or deckhead or from above, having a total area of at least 10% of the total area of the space sides.

  36 Open vehicle spaces are those vehicle spaces which are either open at both ends, or have an opening at one end and are provided with adequate natural ventilation effective over their entire length through permanent openings distributed in the side plating or deckhead or from above, having a total area of at least 10% of the total area of the space sides.

  37 Passenger ship is a ship as defined in regulation I/2(f).

  38 Prescriptive requirements means the construction characteristics, limiting dimensions, or fire safety systems specified in parts B, C, D, E or G.

  39 Public spaces are those portions of the accommodation which are used for halls, dining rooms, lounges and similar permanently enclosed spaces.

  40 Rooms containing furniture and furnishings of restricted fire risk, for the purpose of regulation 9, are those rooms containing furniture and furnishings of restricted fire risk (whether cabins, public spaces, offices or other types of accommodation) in which:

  • .1 case furniture such as desks, wardrobes, dressing tables, bureaux, or dressers are constructed entirely of approved non-combustible materials, except that a combustible veneer not exceeding 2 mm may be used on the working surface of such articles;

  • .2 free-standing furniture such as chairs, sofas, or tables, are constructed with frames of non-combustible materials;

  • .3 draperies, curtains and other suspended textile materials have qualities of resistance to the propagation of flame not inferior to those of wool having a mass of 0.8 kg/m2 , this being determined in accordance with the Fire Test Procedures Code;

  • .4 floor coverings have low flame-spread characteristics;

  • .5 exposed surfaces of bulkheads, linings and ceilings have low flame-spread characteristics;

  • .6 upholstered furniture has qualities of resistance to the ignition and propagation of flame, this being determined in accordance with the Fire Test Procedures Code; and

  • .7 bedding components have qualities of resistance to the ignition and propagation of flame, this being determined in accordance with the Fire Test Procedures Code.

  41 Ro-ro spaces are spaces not normally subdivided in any way and normally extending to either a substantial length or the entire length of the ship in which motor vehicles with fuel in their tanks for their own propulsion and/or goods (packaged or in bulk, in or on rail or road cars, vehicles (including road or rail tankers), trailers, containers, pallets, demountable tanks or in or on similar stowage units or other receptacles) can be loaded and unloaded normally in a horizontal direction.

  42 Ro-ro passenger ship means a passenger ship with ro-ro spaces or special category spaces.

  43 Steel or other equivalent material means any non-combustible material which, by itself or due to insulation provided, has structural and integrity properties equivalent to steel at the end of the applicable exposure to the standard fire test (e.g. aluminium alloy with appropriate insulation).

  44 Sauna is a hot room with temperatures normally varying between 80°-120°C where the heat is provided by a hot surface (e.g. by an electrically-heated oven). The hot room may also include the space where the oven is located and adjacent bathrooms.

  45 Service spaces are those spaces used for galleys, pantries containing cooking appliances, lockers, mail and specie rooms, storerooms, workshops other than those forming part of the machinery spaces, and similar spaces and trunks to such spaces.

  46 Special category spaces are those enclosed vehicle spaces above and below the bulkhead deck, into and from which vehicles can be driven and to which passengers have access. Special category spaces may be accommodated on more than one deck provided that the total overall clear height for vehicles does not exceed 10 m.

  47 A standard fire test is a test in which specimens of the relevant bulkheads or decks are exposed in a test furnace to temperatures corresponding approximately to the standard time-temperature curve in accordance with the test method specified in the Fire Test Procedures Code.

  48 Tanker is a ship as defined in regulation I/2(h).

  49 Vehicle spaces are cargo spaces intended for carriage of motor vehicles with fuel in their tanks for their own propulsion.

  50 Weather deck is a deck which is completely exposed to the weather from above and from at least two sides.

  51 Safe area in the context of a casualty is, from the perspective of habitability, any area(s) which is not flooded or which is outside the main vertical zone(s) in which a fire has occurred such that it can safely accommodate all persons onboard to protect them from hazards to life or health and provide them with basic services.

  52 Safety centre is a control station dedicated to the management of emergency situations. Safety systems' operation, control and/or monitoring are an integral part of the safety centre.

  53 Cabin balcony is an open deck space which is provided for the exclusive use of the occupants of a single cabin and has direct access from such a cabin.

 54 Fire damper is, for the purpose of implementing regulation 9.7 adopted by resolution MSC.365(93), as may be amended, a device installed in a ventilation duct, which under normal conditions remains open allowing flow in the duct, and is closed during a fire, preventing the flow in the duct to restrict the passage of fire. In using the above definition the following terms may be associated:

  • .1 automatic fire damper is a fire damper that closes independently in response to exposure to fire products;

  • .2 manual fire damper is a fire damper that is intended to be opened or closed by the crew by hand at the damper itself; and

  • .3 remotely operated fire damper is a fire damper that is closed by the crew through a control located at a distance away from the controlled damper.

 55 Smoke damper is, for the purpose of implementing regulation 9.7 adopted by resolution MSC.365(93), as may be amended, a device installed in a ventilation duct, which under normal conditions remains open allowing flow in the duct, and is closed during a fire, preventing the flow in the duct to restrict the passage of smoke and hot gases. A smoke damper is not expected to contribute to the integrity of a fire rated division penetrated by a ventilation duct. In using the above definition the following terms may be associated:

  • .1 automatic smoke damper is a smoke damper that closes independently in response to exposure to smoke or hot gases;

  • .2 manual smoke damper is a smoke damper intended to be opened or closed by the crew by hand at the damper itself; and

  • .3 remotely operated smoke damper is a smoke damper that is closed by the crew through a control located at a distance away from the controlled damper.

 56 Vehicle carrier means a cargo ship which only carries cargo in ro-ro spaces or vehicle spaces, and which is designed for the carriage of unoccupied motor vehicles without cargo, as cargo.

57 Helicopter landing area is an area on a ship designated for occasional or emergency landing of helicopters but not designed for routine helicopter operations.

58 Winching area is a pick-up area provided for the transfer by helicopter of personnel or stores to or from the ship, while the helicopter hovers above the deck.


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