1974年国际海上人命安全公约1990年修正案 AMENDMENTS TO THE INTERNATIONAL CONVENTION FOR THE SAFETY OF LIFEATSEA， 1974
AMENDMENTS TO THE INTERNATIONAL CONVENTION FOR THE SAFETY OF LIFEATSEA， 1974
[Adopted on 25 May 1990 by Resolution MSC. 19（58）]
TABLE OF CONTENTS CHAPTER II-1 CONSTRUCTION-SUBDIVISION AND STABILITY， MACHINERY ANDELECTRICAL INSTALLATIONS Addition of new Part B-1 PART B-1 SUBDIVISION AND DAMAGE STABILITY OF CARGO SHIPS
25-3 Required subdivision index “R”
25-4 Attained subdivision index “A”
25-5 Calculation of the factor “P ”
25-6 Calculation of the factor “S ”
25-8 Stability information
25-9 Openings in watertight bulkheads and internal decks in cargoships.
25-10 External openings in cargo shipsAMENDMENTS TO THE INTERNATIONAL CONVENTION FOR THE SAFETY OF LIFE AT SEA，1974[Adopted on 25 May 1990 by Resolution MSC .19（58）]
CHAPTER II-1 CONSTRUCTION-SUBDIVISION AND STABILITY， MACHINERY ANDELECTRICAL INSTALLATIONS
Insert the following new part B-1， comprising Regulations 25-1 to25-10， after existing part B： “PART B-1 SUBDIVISION AND DAMAGE STABILITYOF CARGO SHIPS
[ The Maritime Safety Committee， in adopting the Regulationscontained in part B-1， invited Administrations to note that theRegulations should be applied in conjunction with the explanatory notesdeveloped by the Organization in order to ensure their uniformapplication.] （This part applies to cargo ships constructed on or after 1February 1992）
Regulation 25-1 Application
1 The requirements in this part shall apply to cargo ships over 100 min length （“Ls”） but shall exclude those ships which are shown to complywith subdivision and damage stability regulations in other instruments developed by the Organization.
[ Ships shown to comply with the following Regulations may beexcluded from the application of part B-1：
。1 annex 1 to MARPOL 73/78；
。2 International Bulk Chemical Code （resolutions MSC. 4（48） andMSC. 10（54））， as amended；
。3 International Gas Carrier Code （resolution MSC. 5（48））；
。4 Guidelines for the Design and Construction of Offshore SupplyVessels （resolution A. 469 （XII））；
。5 Code of Safety for Special Purpose Ships （resolution A. 534（13））；
。6 damage stability requirements of Regulation 27 of the 1966 LoadLine Convention as applied in compliance with resolutions A. 320（IX） andA. 514（13）， provided that in the case of ships to which Regulation 27（9）apply， main transverse watertight bulkheads， to be considered effective，are spaced according to paragraph （12） （f） of resolution A. 320（IX）。]
2 Any reference hereinafter to Regulations refers to the set ofRegulations contained in this part.
3 The Administration may for a particular ship or group of shipsaccept alternative arrangements， if it is satisfied that at least thesame degree of safety as represented by these Regulations is achieved. AnyAdministration which allows such alternative arrangements shallcommunicate to the Organization particulars there of.
Regulation 25-2 Definitions
For the purpose of these Regulations， unless expressly providedotherwise：
1.1 Subdivision load line is a waterline used in determining thesubdivision of the ship.
1.2 Deepest subdivision load line is the subdivision load line whichcorresponds to the summer draught to be assigned to the ship.
1.3 Partial load line is the light ship draught plus 60% of thedifference between the light ship draught and deepest subdivision loadline.
2.1 Subdivision length of the ship （“Ls”） is the greatest projectedmoulded length of that part of the ship at or below deck or decks limitingthe vertical extent of flooding with the ship at the deepest subdivisionload line.
2.2 Mid-length is the mid point of the subdivision length of the ship.
2.3 Aft terminal is the aft limit of the subdivision length.
2.4 Forward terminal is the forward limit of the subdivision length.
3 Breadth （“B”） is the greatest moulded breadth of the ship at orbelow the deepest subdivision load line.
4 Draught （“d”） is the vertical distance from the moulded baseline atmid-length to the waterline in question.
5 Permeability （“ μ”） of a space is the proportion of the immersedvolume of that space which can be occupied by water.
Regulation 25-3 Required subdivision index “R”
1 These Regulations are intended to provide ships with a minimumstandard of subdivision.
2 The degree of subdivision to be provided shall be determined by therequired subdivision index “R”， as follows：
| 1/3 |
| R=(0.002+0.0009Ls) | where "Ls" is in metres.
Regulation 25-4 Attained subdivision index "A"
1 The attained subdivision index "A", calculated in accordance with
this Regulation, shall not be less than the required subdivision index
"R", calculated in accordance with paragraph 2 of Regulation 25-3.
2 The attained subdivision index "A" shall be calculated for the ship
by the following formula:
| A=∑p s |
| i i |
“i” represents each compartment or group of compartments underconsideration，
“p ” accounts for the probability that only the compartment or group
i of compartments under consideration may be flooded， disregardingany horizontal subdivision，
“s ” accounts for the probability of survival after flooding the
i compartment or group of compartments under consideration，including the effects of any horizontal subdivision.
3 In calculating “A”， level trim shall be used.
4 This summation covers only those cases of flooding which contributeto the value of the attained subdivision index “A”。
5 The summation indicated by the above formula shall be taken over theship's length for all cases of flooding in which a single compartment ortwo or more adjacent compartments are involved.
6 wherever wing compartments are fitted， contribution to the summationindicated by the formula shall be taken for all cases of flooding in whichwing compartments are involved； and additionally， for all cases ofsimultaneous flooding of a wing compartment or compartments and theadjacent inboard compartment or compartments， assuming a rectangularpenetration which extends to the ship's centreline， but excludes damage toany centreline bulkhead.
7 The assumed vertical extent of damage is to extend from the baselineupwards to any watertight horizontal subdivision above the waterline orhigher. However， if a lesser extent will give a more severe result， suchextent is to be assumed.
8 If pipes， ducts or tunnels are situated within assumed floodedcompartments， arrangements are to be made to ensure that progressiveflooding cannot there by extend to compartments other than those assumedflood. However， the Administration may permit minor progressive floodingif it is demonstrated that its effects can be easily controlled and thesafety of the ship is not impaired.
9 In the flooding calculations carried out according to theRegulations， only one breach of the hull need be assumed.
Regulation 25-5 Calculation of the Factor “Pi ”
1 The factor “p ” shall be calculated according to paragraph 1.1 as
i appropriate， using the following notations：
X =the distance from the aft terminal of “L ” to the foremost
1 s portion of the aft end of the compartment being considered；
X =the distance from the aft terminal of “L ” to the aftermost
2 s portion of the forward end of the compartment being considered；
E =X /L
1 1 s
| E =X /L |
| 2 2 s |
E=E +E -1
| J=E - E |
| 2 1 |
J'=J-E, if E≥0
J'=J+E, if E＜0
The maximum nondimensional damage length
| J =48/L , but not more than 0.24. |
| max s |
The assumed distribution density of damage location along the
a=1.2+0.8E, but not more than 1.2.
The assumed distribution function of damage location along the
| y=J/J |
| max |
| 2 |
| q=0.4F (J ) |
| 2 max |
| 3 |
| 2 y |
| F = y - ---, if y＜1, |
| 1 3 |
F =y- ---, otherwise;
| 3 4 |
| y y |
| F =--- - ---, if y＜1, |
| 2 3 12 |
y y 1
F =--- - --- + ---, otherwise.
2 2 3 12
1.1 The factor “p ” is determined for each single compartment：
1.1.1 Where the compartment considered extends over the entire shiplength， “L ”：
1.1.2 Where the aft limit of the compartment considered coincides withthe aft terminal：
1.1.3 Where the forward limit of the compartment considered coincideswith the forward terminal：
1.1.4 When both ends of the compartment considered are inside the aftand forward terminals of the ship length， “L ”：
1.1.5 In applying the formulae of paragraphs 1.1.2， 1.1.3 and 1.1.4，where the compartment considered extends over the “mid-length”， theseformulae values shall be reduced by an amount determined according to theformula for “q”， in which “F ” is calculated taking “y” to be J'/J
2 Wherever wing compartments are fitted， the “p ” -value for a wing
i compartment shall be obtained by multiplying the value， as determined inparagraph 3， by the reduction factor “r” according to subparagraph 2.2，which represents the probability that the inboard spaces will not beflooded.
2.1 The “P ”-value for the case of simultaneous flooding of a wing and
i adjacent inboard compartment shall be obtained by usingthe formulae of paragraph 3， multiplied by the factor （1-r）。
2.2 The reduction factor “r” shall be determined by the followingformulae：
For J ≥0.2b/B：
r=——（2.3 + ——） + 0.1， if b/B ≤0.2
r=（—— + —— + 0.36）， if b/B＞0.2
For J ＜0.2 b/B the reduction factor “r” shall be determined by linearinterpolation between
r=1， for J=0
r=as for the case where J ≥0.2b/B， for J=0.2b/B，
b=the mean transverse distance in metres measured at rightangles to the centreline at the deepest subdivision load line between theshell and a plane through the outermost portion of and parallel to thatpart of the longitudinal bulkhead which extends between the longitudinal limits used in calculating the factor “p ”。
3 To evaluate “p” for compartments taken singly the formulae inparagraphs 1 and 2 shall be applied directly.
3.1 To evaluate the “p”-values attributable to groups of compartmentsthe following applies：
for compartments taken by pairs：
| p =p -p -p |
| i 12 1 2 |
p =p -p -p ， etc.
i 23 2 3
for compartments taken by groups of three：
p =p -p -p +p
i 123 12 23 2
p =p -p -p +p ， etc.
i 234 23 34 3
for compartments taken by groups of four：
p =p -p -p +p
i 1234 123 234 23
p =p -p -p +p ， etc.
i 2345 234 345 34
p ， p ， p ， etc.，
12 23 34
p ， p ， p ， etc. and
123 234 345
p ， p ， p ， etc.
1234 2345 3456
shall be calculated according to the formulae in paragraphs 1 and 2for a single compartment whose nondimensional length “J” corresponds tothat of a group consisting of the compartments indicated by the indicesassigned to “p”。
3.2 The factor “P ” for a group of three or more adjacent compartments
i equals zero if the nondimensional length of such agroup nines the nondimensional length of the aftermost and foremostcompartments in the group is greater than “J ”。
Regulation 25-6 Calculation of Factor “Si”
1 The factor “s ”， shall be determined for each compartment or group
iof compartments ac cording to the following：
1.1 in general for any condition of flooding from any initial loadingcondition “s” shall be
s=C √0.5(GZ )(range)
with C=1, if θe ≤25°
C=0, if θe ＞30°
C= √ 30-θe
GZ =maximum positive righting lever （in metres） within the
max range as given below but not more than 0.1 m；
range=range of positive righting levers beyond the angle ofequilibrium （in degrees） but not more than 20 °； however， the range shallbe terminated at the angle where openings not capable of being closedweathertight are immersed；
θe=final equilibrium angle of heel （in degrees）；
1.2 s=0 where the final waterline taking into account sinkage， heeland trim， immerses the lower edge of openings through which progressiveflooding may take place. Such opening shall include air-pipes， ventilatorsand openings which are closed by means of weathertight doors or hatchcovers， and may exclude those openings closed by means of watertightmanhole covers and flush scuttles， small watertight hatch covers whichmaintain the high integrity of the deck， remotely operated slidingwatertight doors， access doors and access hatch covers， of watertightintegrity， normally closed at sea and sidescuttles of the non-openingtype. However， if the compartments so flooded are taken into account inthe calculations the requirements of this Regulation shall be applied.
1.3 For each compartment or group of compartments “s ” shall be
i weighted according to draught consideration as follows：
s =0.5s +0.5s
i l p
“s ” is the “s”-factor at the deepest subdivision load line；
“s ” is the “s”-factor at the partial load line.
2 For all compartments forward of the collision bulkhead， the“s”-value， calculated assuming the ship to be at its deepest subdivisionload line and with assumed unlimited vertical extent of damage is to beequal to 1.
3 Wherever a horizontal subdivision is fitted above the waterline inquestion the following applies.
3.1 The “s”-value for the lower compartment or group of compartmentsshall be obtained by multiplying the value as determined in subparagraph1.1 by the reduction factor “v ” ac cording to subparagraph 3.3， which
i represents the probability that the spaces above the horizontalsubdivision will not be flooded.
3.2 In cases of positive contribution to index “A” due to simultaneousflooding of the spaces above the horizontal subdivision， the resulting“s”-value for such a compartment or group of compartments shall beobtained by an increase of the value as determined by subparagraph 3.1 bythe “s”-value for simultaneous flooding according to subparagraph 1.1， multiplied by the factor （1-v ）。
3.3 The probability factor “v ” shall be calculated according to：
v = ——， for the assumed flooding up to the horizontal
i H -d
maxsubdivision above the subdivision load line， where “H” is to be restrictedto a height of
v =1， if the uppermost horizontal subdivision in way of the
iassumed dam aged region is below “H ”，
“H” is the height of the horizontal subdivision above the baseline （inmetres） which is assumed to limit the vertical extent of damage，
“H ” is the maximum possible vertical extent of damage above the
max baseline （in metres）， or
| L |
| s |
| H =d+0.056L (1- ---), if L ≤250m; |
| max s 500 s |
| H =d+7, if L ＞250m |
| max s |
whichever is less.
Regulation 25-7 Permeability
For the purpose of the subdivision and damage stability calculationsof the Regulations， the permeability of each space or part of a spaceshall be as follows：
Appropriated to stores 0.60
Occupied by accommodation 0.95
Occupied by machinery 0.85
Void spaces 0.95
Dry cargo spaces 0.7
Intended for liquid 0 or 0.95
[ whichever results in the more severe requirements.]
Regulation 25-8 Stability Information
1 The master of the ship shall be supplied with such reliableinformation as is necessary to enable him by rapid and simple means toobtain accurate guidance as to the stability of the ship under varyingconditions of service. The information shall include：
。1 a curve of minimum operational metacentric height （GM） versusdraught which assures compliance with the relevant intact stabilityrequirements and the requirements of Regulations 25-1 to 25-6，alternatively a corresponding curve of the maximum allowable verticalcentre of gravity （KG） versus draught， or with the equivalents of eitherof these curves；
。2 instructions concerning the operation of cross-floodingarrangements； and
。3 all other date and aids which might be necessary to maintainstability after damage.
2 There shall be permanently exhibited， or readily available on thenavigating bridge， for the guidance of the officer in charge of the ship，plans showing clearly for each deck and hold the boundaries of thewatertight compartments， the openings therein with the means of closureand position of any controls thereof， and the arrangements for thecorrection of any list due to flooding. In addition， booklets containingthe aforementioned information shall be made available to the officers ofthe ship.
3 In order to provide the information referred to in 1.1， the limitingGM （or KG） values to be used， if they have been determined fromconsiderations related to the subdivision index， the limiting GM shall bevaried linearly between the deepest subdivision load line and the partialload line. In such cases， for draughts below the partial load line if theminimum GM requirement at this draught results from the calculation of thesubdivision index， then this GM value shall be assumed for lesserdraughts， unless the intact stability requirements apply.
Regulation 25-9 Openings in watertight bulkheads and internaldecks in cargo ships
1 The number of openings in watertight subdivision is to be kept to aminimum compatible with the design and proper working of the ship. Wherepenetrations of watertight bulkheads and internal decks are necessary foraccess， piping， ventilation， electrical cables， etc.， arrangements are tobe made to maintain the watertight integrity. The Administration maypermit relaxation in the water-tightness of openings above the freeboarddeck， provided that it is demonstrated that any progressive flooding canbe easily controlled and that the safety of the ship is not impaired.
2 Doors provided to ensure the watertight integrity of internalopenings which are used while at sea are to be sliding watertight doorscapable of being remotely closed from the bridge and are also to beoperable locally from each side of the bulkhead. Indicators are to beprovided at the control position showing whether the doors are open orclosed， and an audible alarm is to be provided at the door closure. Thepower， control and indicators are to be operable in the event of mainpower failure. Particular attention is to be paid to minimize the effectof control system failure. Each power-operated sliding watertight doorshall be provided with an individual hand-operated mechanism. It shall bepossible to open and close the door by hand at the door itself from bothsides.
3 Access doors and access hatch covers normally closed at sea，intended to ensure the watertight integrity of internal openings， shall beprovided with means of indication locally and on the bridge showingwhether these doors or hatch covers are open or closed. A notice is to beaffixed to each such door or hatch cover to the effect that it is not tobe left open. The use of such doors and hatch cover shall be authorized bythe officer of the watch.
4 Watertight doors or ramps of satisfactory construction may be fittedto internally subdivide large cargo spaces， provided that theAdministration is satisfied that such doors or ramps are essential. Thesedoors or ramps may be hinged， rolling or sliding doors or ramps， butshall not be remotely controlled. Such doors or ramps shall be closedbefore the voyage commences and shall be kept closed during navigation；the time of opening such doors or ramps in port and of closing them beforethe ship leaves port shall be entered in the logbook. Should any of thedoors or ramps be accessible during the voyage， they shall be fitted witha device which prevents unauthorized opening.
5 Other closing appliances which are kept permanently closed at sea toensure the watertight integrity of internal openings shall be providedwith a notice which is to be affixed to each such closing appliance to theeffect that it is to be kept closed. Manholes fitted with closely boltedcovers need not be so marked.
Regulation 25-10 External openings in cargo ships
1 All external openings leading to compartments assumed intact in thedamage analysis， which are below the final damage waterline， are requiredto be watertight.
2 External openings required to be watertight in accordance withparagraph 1 shall be of sufficient strength and， except for cargo hatchcovers， shall be fitted with indicators on the bridge.
3 Openings in the shell plating below the deck limiting the verticalextent of damage shall be kept permanently closed while at sea. Should anyof these openings be accessible during the voyage， they shall be fittedwith a device which prevents unauthorized opening.
4 Notwithstanding the requirements of paragraph 3， the Administrationmay authorize that particular doors may be opened at the discretion of themaster， if necessary for the operation of the ship and provided that thesafety of the ship is not impaired.
5 Other closing appliances which are kept permanently closed at sea toensure the watertight integrity of external openings shall be providedwith a notice affixed to each appliance to the effect that it is to bekept closed. Manholes fitted with closely bolted covers need not be somarked.