CHAPTER II-1
CONSTRUCTION - SUBDIVISION AND STABILITY, MACHINERY AND ELECTRICAL INSTALLATIONS

   PART A-GENERAL

 

   Regulation 1.
Application

 

1.1 Unless expressly provided otherwise, this chapter shall apply to ships the keels of which are laid or which are at a similar stage of construction on or after 1 July 1986.

 

1.2 For the purpose of this chapter, the term "a similar stage of construction" means the stage at which:

 

.1 construction identifiable with a specific ship begins and

 

.2 assembly of that ship has commenced comprising at least 50 tonnes or 1 % of the estimated mass of all structural material, whichever is less.

 

1.3 For the purpose of this chapter:

 

.1 the expression "ships constructed" means "ships the keels of which are laid or which are at a similar stage of construction":

 

.2 the expression "all ships" means "ships constructed before, on or after 1 July 1986";

 

.3 a cargo ship, whenever built, which is converted to a passenger ship shall be treated as a passenger ship constructed on the date on which such a conversion commences.

 

2 Unless expressly provided otherwise, for ships constructed before 1 July 1986, the Administration shall ensure that the requirements which are applicable under chapter II-1 of the International Convention for the Safety of Life at Sea, 1974, as amended by resolution MSC. 1 (XLV), are complied with.

 

3.1 All ships which undergo repairs, alterations, modifications and outfitting related thereto shall continue to comply with at least the requirements previously applicable to these ships. Such ships if constructed before 1 July 1986 shall, as a rule, comply with the requirements for ships constructed on or after that date to at least the same extent as they did before undergoing such repairs, alterations, modifications or outfitting. Repairs, alterations and modifications of a major character and outfitting related thereto shall meet the requirements for ships constructed on or after 1 July 1986 in so far as the Administration deems reasonable and practicable.

 

3.2 Notwithstanding the provisions of paragraph 3.1, passenger ships which undergo repairs, alterations and modifications to meet the requirements of regulation II-l/8.9 shall not be deemed to constitute repairs, alterations and modifications of a major character.

 

4 The Administration of a State may, if it considers that the sheltered nature and conditions of the voyage are such as to render the application of any specific requirements of this chapter unreasonable or unnecessary, exempt from those requirements individual ships or classes of ships entitled to the flag of that State which, in the course of their voyage, do not proceed more than 20 miles from the nearest land.

 

5 In the case of passenger ships which are employed in special trades for the carriage of large numbers of special trade passengers, such as the pilgrim trade, the Administration of the State whose flag such ships are entitled to fly, if satisfied that it is impracticable to enforce compliance with the requirements of this chapter, may exempt such ships from those requirements, provided that they comply fully with the provisions of:

 

.1 the rules annexed to the Special Trade Passenger Ships Agreement, 1971;

 

and

 

.2 the rules annexed to the Protocol on Space Requirements for Special Trade Passenger Ships, 1973.

 

   Regulation 2.
Definitions

 

For the purpose of this Chapter, unless expressly provided otherwise:

 

1.1 "Subdivision load line" is a water-line used in determining the subdivision of the ships.

 

1.2 "Deepest subdivision load line" is the water-line which corresponds to the greatest draught permitted by the subdivision requirements which are applicable.

 

2 "Length of the ships" is the length measured between perpendiculars taken at the extremities of the deepest subdivision load line.

 

3 "Breadth of the ship" is the extreme width from outside of frame to outside of frame at or below the deepest subdivision load line.

 

4 "Draught" is the vertical distance from the moulded base line amidships to the subdivision load line in question.

 

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

 

6 "Margin line" is a line drawn at least 76 mm below the upper surface of the bulkhead deck at side.

 

7 "Permeability of a space" is the percentage of that space which can be occupied by water. The volume of a space which extends above the margin line shall be measured only to the height of that line.

 

8 "Machinery space" is to be taken as extending from the moulded base line to the margin line and between the extreme main transverse watertight bulkheads, bounding the spaces containing the main and auxiliary propulsion machinery, boilers serving the needs of propulsion, and all permanent coal bunkers. In the case of unusual arrangements, the Administration may define the limits of the machinery spaces.

 

9 "Passenger spaces" are those spaces which are provided for the accommodation and use of passengers, excluding baggage, store, provision and mail rooms. For the purposes of regulations II-l /5 and 6, spaces provided below the margin line for the accommodation and use of the crew shall be regarded as passenger spaces.

 

10 In all cases volumes and areas shall be calculated to moulded lines.

 

11 "Weathertight" means that in any sea conditions water will not penetrate into the ship.

 

   Regulation 3.
Definitions relating to parts C, D and E

 

For the purpose of parts C, D and E, unless expressly provided otherwise:

 

1 "Steering gear control system" is the equipment by which orders are transmitted from the navigating bridge to the steering gear power units. Steering gear control systems comprise transmitters, receivers, hydraulic control pumps and their associated motors, motor controllers piping and cables.

 

2 "Main steering gear" is the machinery, rudder actuators, steering gear power units, if any, and ancillary equipment and the means of applying torque to the rudder stock (e.g. tiller or quadrant) necessary for effecting movement of the rudder for the purpose of steering the ships under normal service conditions.

 

3 "Steering gear power unit" is:

 

.1 in the case of electric steering gear, an electric motor and its associated electrical equipment;

 

.2 in the case of electrohydraulic steering gear, an electric motor and its associated electrical equipment and connected pump;

 

.3 in the case of other hydraulic steering gear, a driving engine and connected pump.

 

4 "Auxiliary steering gear" is the equipment other than any part of the main steering gear necessary to steer the ship in the event of failure of the main steering gear but not including the tiller, quadrant or components serving the same purpose.

 

5 "Normal operational and habitable condition" is a condition under which the ship as a whole, the machinery, services, means and aids ensuring propulsion, ability to steer, safe navigation, fire and flooding safety, internal and external communications and signals, means of escape, and emergency boat winches, as well as the designed comfortable conditions of habitability are in working order and functioning normally.

 

6 "Emergency condition" is a condition under which any services needed for normal operational and habitable conditions are not in working order due to failure of the main source of electrical power.

 

7 "Main source of electrical power" is a source intended to supply electrical power to the main switchboard for distribution to all services necessary for maintaining the ship in normal operational and habitable conditions.

 

8 "Dead ship condition" is the condition under which the main propulsion plant, boilers and auxiliaries are not in operation due, to the absence of power.

 

9 "Main generating station" is the space in which the main source of electrical power is situated.

 

10 "Main switchboard" is a switchboard which is directly supplied by the main source of electrical power and is intended to distribute electrical energy to the ship's services.

 

11 "Emergency switchboard" is a switchboard which in the event of failure of the main electrical power supply system is directly supplied by the emergency source of electrical power or the transitional source of emergency power and is intended to distribute electrical energy to the emergency services.

 

12 "Emergency source of electrical power" is a source of electrical power, intended to supply the emergency switchboard in the event of failure of the supply from the main source of electrical power.

 

13 "Power actuating system" is the hydraulic equipment provided for supplying power to turn the rudder stock, comprising a steering gear power unit or units, together with the associated pipes and fittings, and a rudder actuator. The power actuating systems may share common mechanical components, i.e., tiller, quadrant and rudder stock, or components serving the same purpose.

 

14 "Maximum ahead service speed" is the greatest speed which the ship is designed to maintain in service at sea at the deepest sea-going draught.

 

15 "Maximum astern speed" is the speed which it is estimated the ship can attain at the designed maximum astern power at the deepest sea-going draught.

 

16 "Machinery spaces" are all machinery spaces of category A and all other spaces containing propelling 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.

 

17 "Machinery spaces of category A" are those spaces and trunks to such spaces which contain:

 

.1 internal combustion machinery used for main propulsion; or

 

.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.

 

18 "Control stations" are those spaces in which the snip'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.

 

19 "Chemical tanker" is a cargo ship constructed or adapted and used for the carriage in bulk of any liquid product listed in either:

 

.1 chapter 17 of the International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk adopted by the Maritime Safety Committee by resolution MSC.4(48) hereinafter referred to as "the International Bulk Chemical Code", as may be amended by the Organization; or

 

.2 chapter VI of the Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk adopted by the Assembly of the Organization by resolution A.212(VII), hereinafter referred to as "the Bulk Chemical Code", as has been or may be amended by the Organization;

 

whichever is applicable.

 

20 "Gas carrier" is a cargo ship constructed or adapted and used for the carriage in bulk of any liquefied gas or other products listed in either:

 

.1 chapter 19 of the International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk adopted by the Maritime Safety Committee by resolution MSC.5(48) hereinafter referred to as "the International Gas Carrier Code", as may be amended by the Organization; or

 

.2 chapter XIX of the Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk adopted by Assembly of the Organization by resolution A.328 (IX), hereinafter referred to as "the Gas Carrier Code", as has been or may be amended by the Organization;

 

whichever is applicable.

 

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 water-line corresponding to the assigned summer freeboard and the lightweight of the ship.

 

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

 

   PART В - SUBDIVISION AND STABILITY*

 

(Part В applies to passenger ships and to cargo ships, as indicated in the regulations)

 

______________________

* Instead of the requirements in this part, the Regulations on Subdivision and Stability of Passenger Ships as an Equivalent to Part В of chapter II of the International Convention for the Safety of Life at Sea, 1960, adopted by the Organization by resolution A.265(VIII), may be used, if applied in their entirety.

 

   Regulation 4.
Floodable length in passenger ships

 

1 The floodable length at any point of the length of a ship shall be determined by a method of calculation which takes into consideration the form, draught and other characteristics of the ship in question.

 

2 In a ship with a continuous bulkhead deck, the floodable length at a given point is the maximum portion of the length of the ship, having its centre at the point in question, which can be flooded under the definite assumptions set forth in regulation II-l/5 without the ship being submerged beyond the margin line.

 

3.1 In the case of a ship not having a continuous bulkhead deck, the floodable length at any point may be determined to an assumed continuous margin line which at no point is less than 76 mm below the top of the deck (at side) to which the bulkheads concerned and the shell are carried watertight.

 

3.2 Where a portion of an assumed margin line is appreciably below the deck to which bulkheads are carried, the Administration may permit a limited relaxation in the water-tightness of those portions of the bulkheads which are above the margin line and immediately under the higher deck.

 

   Regulation 5.
Permeability in passenger ships

 

1.1 The definite assumptions referred to in regulation II-l/4 relate to the permeabilities of the spaces below the margin line.

 

1.2 In determining the floodable length, a uniform average permeability shall be used throughout the whole length of each of the following portions of the ship below the margin line:

 

.1 the machinery space as defined in regulation II-1/2;

 

.2 the portion forward of the machinery space; and

 

.3 the portion abaft the machinery space.

 

2.1 The uniform average permeability throughout the machinery space shall be determined from the formula:

 

 

 

where:

 

a — the volume of the passenger spaces, as defined in regulation II-1/2, which are situated below the margin line within the limits of the machinery space;

с — the volume of between deck spaces below the margin line within the limits of the machinery space which are appropriated to cargo, coal or stores;

 

v — the whole volume of the machinery space below the margin line.

 

2.2 Where it is shown to the satisfaction of the Administration that the average permeability as determined by detailed calculation is less than that given by the formula, the detailed calculated value may be used. For the purpose of such calculation, the permeability of passenger spaces, as defined in regulation II-1/2, shall be taken as 95, that of all cargo, coal and store spaces as 60, and that of double bottom, oil fuel and other tanks at such value as may be approved in each case.

 

3 Except as provided in paragraph 4, the uniform average permeability throughout the portion of the ship forward of or abaft the machinery space shall be determined from the formula:

 

 

 

where:

 

a — the volume of the passenger spaces, as defined in regulation II-l/2 which are situated below the margin line, forward of or abaft the machinery space, and

 

v — the whole volume of the portion of the ship below the margin line forward of or abaft the machinery space.

 

4.1 In the case of special subdivision required in regulation II-1/6.5, the uniform average permeability throughout the portion of the ship forward of or abaft the machinery space shall be

 

 

where:

 

b — the volume of the spaces below the margin line and above the tops of floors, inner bottom, or peak tanks, as the case may be, which are appropriate to and used as cargo spaces, coal or oil fuel bunkers, store rooms, baggage and mail rooms, chain lockers and fresh water tanks, forward of or abaft the machinery space; and

 

v — the whole volume of the portion of the ship below the margin line forward of or abaft the machinery space.

 

4.2 In the case of ships engaged on services where the cargo holds are not generally occupied by any substantial of cargo, no part of the cargo spaces is to be included in calculating "b".

 

5 In the case of unusual arrangements the Administration may allow, or require, a detailed calculation of average permeability for the portions forward of or abaft the machinery space. For the purpose of such calculation, the permeability of passenger spaces as defined in regulation II-1/2 shall be taken as 95, that of spaces containing machinery as 85, that of all cargo, coal and store spaces as 60, and that of double bottom, oil fuel and other tanks at such value as may be approved in each case.

 

6 Where a between deck compartment between two watertight transverse bulkheads contains any passenger or crew space, the whole of that compartment, less any space completely enclosed within permanent steel bulkheads and appropriated to other purposes, shall be regarded as passenger space. Where, however, the passenger or crew space in question in completely enclosed within permanent steel bulkheads, only the space so enclosed need be considered as passenger space.

 

   Regulation 6.
Permissible length of compartments in passenger ships

 

1 Ships shall be as efficiently subdivided as is possible having regard to the nature of the service for which they are intended. The degree of subdivision shall vary with the length of the ship and with the service, in such manner that the highest degree of subdivision corresponds with the ships of greatest length, primarily engaged in the carriage of passengers,

 

2 Factor of subdivision

 

2.1 The maximum permissible length of a compartment having its centre at any point in the ship's length is obtained from the floodable length by multiplying the latter by an appropriate factor called the factor of subdivision.

 

2.2 The factor of subdivision shall depend on the length of the ship, and for a given length shall vary according to the nature of the service for which the ship is intended. It shall decrease in a regular and continuous manner:

 

.1 as the length of the ship increases, and

 

.2 from a factor A, applicable to ships primarily engaged in the carriage of cargo, to a factor B, applicable to ships primarily engaged in the carriage of passengers.

 

2.3 The variations of the factors A and В shall be expressed by the following formulae (1) and (2) where L is the length of the ship as defined in regulation II-1/2:

 

 

3 Criterion of service

 

3.1 For a ship of given length the appropriate factor of subdivision shall be determined by the criterion of service numeral (hereinafter called the criterion numeral) as given by the following formulae (3) and (4) where:

 

C_s — the criterion numeral;

 

L — the length of the ship (metres), as defined in regulation