Solas Explainatory

SOLAS

Consolidated Edition 2009

with

Explanatory Notes

(Res. MSC.281(85))

Applicable to Passenger and Cargo Ships of all

Sizes

&

Dry Cargo Ships with Length => 80 m

with keels laid on or after 1

January, 2009

KEY TO COLOUR CODES and FONTS USED IN THIS DOCUMENT SOLAS Consolidated Edition 2009; Current SOLAS text

Resolution MSC.281(85); Current Explanatory Notes (EN)

Regulation 2.9 (ref. SLF 52/17/6 - Norway); Proposed changes to SOLAS text with ref. Regulation 4.3 (ref. SLF 52/3/3 - Germany) Proposed changes to EN (with ref.)

Regulation 4.1 (ref. SLF 52/17/6 - Norway) Proposed changes to footnotes (with ref.) [Coordinator’s Note:] Guidance and suggested minor changes MSC Circulars MSC Circulars referred to in the text Round 1/2 Discussion:

Q1B Round 3 questions for discussion at SLF53 Agreed Regulatory Text Changes Changes to SOLAS agreed in SLF53/WP.6 Agreed EN Text Changes Changes to EN text agreed in SLF 53/WP.6 Rejected Regulatory Text Changes Changes to SOLAS rejected at SLF 53 Rejected EN Text Changes Changes to EN text rejected at SLF 53 Q1C Round 4 questions for 2011 CG

Q1D Questions for discussion at SLF53

Proposed Regulatory Text Changes Changes to SOLAS proposed by 2011 CG Proposed EN Text Changes Changes to EN text proposed by 2011 CG

UPDATES TO SOLAS 2009 AMENDMENTS

To simplify the task of discussing and agreeing updates to the SOLAS regulations, this document includes the full text of the SOLAS Consolidated Edition 2009 in black Ariel 11 font and the explanatory notes from Resolution MSC.281(85) in red Ariel 11 italic font. Any MSC Circulars referred to in the regulations or explanatory notes are also included in black Times New Roman 11 font. Most of the text is in Word though some sections containing complex formulae and figures use Adobe .pdf and cannot be edited.

Changes to be discussed by this CG, including suggestions for possible amendments to SOLAS 2009, are shown in blue and are taken largely from SLF 51/3/2 to 51/3/7 and 52/17/1 to 52/17/6 (see Table 1 below). Proposed amendments to the explanatory notes taken from the above papers are highlighted in green and proposed amendments to the footnotes are highlighted in turquoise (see in particular SLF 52/WP.5, Agenda Item 14). Each proposed change to the regulations, EN or footnotes is inserted into the text at the relevant point with a space for questions and comments.

Some minor suggestions for changing the text are highlighted in yellow for consideration by the CG (see Regs 13.11.1, 15.4, 15.5.1 & 35-1.2.3, for example). Changes needed to the 2009 Consolidated text already agreed in MSC.269(85) are similarly highlighted.

Ref.

Date

By

Subject

Status

SLF 51/3/2 10/04/08 Sweden+US SDS CG report for possible future improvements to SOLAS Ch II-1 regulations; includes the following

Reg 1 - Application; para 1.3.4 Reg 5-1 - Information to the master para. 3

para. 4

Reg 7 - Index A; para 2 para. 6

Reg 7-1 - Calculation of factor p_i; para 1

para. 1.2

Reg 7-2 - Calculation of factor s_i; para 2 para. 4

para. 4.1.1 paras 5.2 and 5.3 Reg 8 - Clarify N formula; paras 3.2-3.5

Reg 9 - Double bottoms; para. 8 Reg 12 - s = 1 fwd of collision bhd proposed new para.

Reg17 - WT integrity above bhd dk para. 3

Reg 22 - Clarify heading Reg 24 - Clarify heading

Reg 35-1 - Mods may be needed

For this CG to consider

Ref.

Date

By

Subject

Status

51/3/3

29/04/08 Germany Status of the Explanatory Notes (proposal to make some mandatory)

Not confirmed. Germany reserves position. (Ref. 51/17/3.21) SLF 51/3/4

09/05/08 IACS Reg 12.5.1 Requirements for pipes piercing collision bulkheads

For this CG to consider

(Ref.51/17/Annex 3) SLF

51/3/5

09/05/08 IACS Reg 9.3 - Interpretation of DB height Not accepted (Ref. 51/WP.1para 6) SLF

51/3/6

22/05/08 China Reg 5-1/3 and /4 - Proposed mods to EN for trim range and critical KG/GM curves

Accepted

EN already amended SLF

51/3/7

23/05/08 Norway Reg 13.4; main or aux mchy separated by longitudinal bhd

Accepted EN amended SLF

51/17

28/08/08 Secretariat Report from SLF 51 to MSC85 covering Agenda Item 3; see paras 3.1 – 3.22 SLF

52/17/1

26/10/09 Germany Reg 7-2 - Uniform application of cross-flooding provisions

For this CG to consider SLF

52/17/2

26/10/09 Germany Reg 19 - Damage control information

“ SLF

52/17/3

19/11/09 Finland Reg 7-1 - Enhancement to EN

“ SLF

52/17/4

20/11/09 Norway Proposes amendments to the following Reg 5-1 - Information to Master

Reg 7 - Index A; mod 7.1 .2 & add 7.3 Reg 4 - footnote Regs 5-1.3, 5-1.4 and 7.2 EN Regs 7.1 and 7.2 EN “ SLF 52/17/5

20/11/09 Norway These are comments on SLF 51/3/2:- Reg 1 - Application; para 1.3.4

Reg 7 - Index A, 1 free surface; para 6 Reg 7-1 - Calc of factor p_i; paras 1 &1.2 Reg 7-2 - Calc of factor s_i; para 4 Reg 8 - Keep text for N; para 3.2 to .5 Reg 35-1 - Clarify L & N; paras 3.2 .4 .9

“

SLF 52/17/6

20/11/09 Norway Further proposed amendments to:- Reg 2 - Definitions in paras 9 and 13 Reg 4 - General; para 1

Reg 5 - Intact Stability; para 1

Reg 5-1- Stability info to master; para 4 Reg 7-2 - Calculation of factor si;para 2 Reg 8 - Consistent use of L; factor s_i Reg 12 - New para for s_i = 1; collsn bhd Reg 17 - WT integrity; para 3 and EN Reg 20 - should not be limited to pax ships; para 1 – add “ship to be upright etc”; propose to add heel tolerance.

Ref.

Date

By

Subject

Status

85/23/1

18/06/08 UK Reg 4 - proposal to delete footnote .4 and update references to remaining footnotes such as .6 & .7 as necessary

For this CG to consider SLF 52/ WP.5/ 14.2

29/1/10 S-C Reg 4 – Germany requests footnotes .6 and .7 to be considered for deletion “ Res.

MSC. 269(85)

Adopted 4/12/08

MSC Part A reg 2 ; new para 27 Part B-1 reg 5; change to heading ; new sentence in para 1

Not in 2009 Consolidated Ed. Highlighted in yellow in this doc Rpt of CSSF WG v04

June ‘10 CLIA/CSSF* Reg 4 – MARPOL to be excluded from Part B-1 damage

Reg. 7-2.5.3, delete “at each boundary” Reg. 2.11; additional text

Reg. 5-1.3/4 EN2; text changes Reg. 7.2; mods to 52/17/4 proposals Reg. 7.5; change to centreline text Reg. 7.7; EN 1 extra text – valve size Reg. 7.7; EN2 clarification – pipe area Reg. 7-1; addition to 52/17/3 – diagram Reg. 7-1.1.2 EN 12 – as for 7.7 EN1 Reg. 7-2.2 EN 1-4; various mods. Reg. 7-2.5.2.2 EN 1,2&5; horiz Esc R Reg. 9.2; additional text + diagram Reg 17.1; remove “sliding”

For this CG to Consider in R2 “ “ “ Table 1

Papers containing proposed changes to SOLAS 2009 regulations, footnotes and Explanatory Notes

* The working group of the CSSF has identified a number of smaller corrections and additions to SOLAS2009 II-1 and the corresponding explanatory notes. Only those proposals are presented in this paper which have supported by a clear majority of the working group members. In addition some topics have been identified, where no consensus could be reached, but which are worth to be further discussed in the ISCG and at the SDS working group during SLF53.

SOLAS Regulations as amended on 1/1/2009

This document contains the amendments to the old SOLAS Chapter II-1 Parts A, B and B-1 which have been completely replaced by the following regulations now incorporated into the SOLAS Consolidated Edition 2009. Regulations shown in red have EN.

CONTENTS

Part A - General

Regulation 1 ...Application

Regulation 2 ...Definitions

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

Part B - Subdivision and stability

Regulation 4 ...General

Part B-1 - Stability

Regulation 5 ...Intact stability information

Regulation 5-1 ...Stability information to be supplied to the master

Regulation 6 ...Required subdivision index R

Regulation 7 …...Attained subdivision index A

Regulation 7-1 ...Calculation of the factor p

Regulation 7-2 ...Calculation of the factor s

Regulation 7-3 …...Permeability

Regulation 8 ...Special requirements concerning passenger ship stability

Regulation 8-1 ...System capabilities

and operational information

after a

flooding casualty on passenger ships

Part B-2 - Subdivision, watertight and weathertight Integrity

Regulation 9 ....Double bottoms in passenger ships and cargo ships other than tankers

Regulation 10 ...Construction of watertight bulkheads

Regulation 11 …...Initial testing of watertight bulkheads etc

Regulation 12 …...Peak and machinery space bulkheads, shaft tunnels, etc

Regulation 13 …………..Openings in watertight bulkheads below the bulkhead deck in

passenger ships

Regulation 13-1...Openings in watertight bulkheads and internal decks in cargo ships

Regulation 14 ...Passenger ships carrying goods vehicles and accompanying personnel

Regulation 15 ...Openings in the shell plating below the bulkhead deck of passengers

ships and the freeboard deck of cargo ships

Regulation 15-1 ...External openings in cargo ships

Regulation 16 ...Construction and initial tests of watertight doors, sidescuttles etc

Regulation 16-1 ...Construction and initial tests of watertight decks, trunks etc

Regulation 17 ....Internal watertight integrity of passenger ships above the bulkhead deck

Regulation 17-1 …………Integrity of the hull and superstructure, damage prevention and

control on ro-ro passenger ships

Part B-3 - Subdivision load line assignment for passenger ships

Regulation 18 ....Assigning, marking and recording of subdivision load lines for

passenger ships

Part B-4 - Stability management

Regulation 19 ...Damage Control Information

Regulation 20 ... ...Loading of [passenger] Ships

[See Q53 – proposal to delete “Passenger” rejected by WG at SLF 53. But now see Q53D]

Regulation 21 ...Periodical operation and inspection of watertight doors, etc.,

in passenger ships

Regulation 22 ...Prevention and control of water ingress, etc. [in passenger ships and

Regulation 22-1 ...Flooding detection systems for passenger ships carrying 36 or more

persons constructed on or after 1/7/2010

Regulation 23 ...Special requirements for ro-ro passenger ships

Regulation 24 ...[ Additional measures for the] [Additional requirements for]

prevention and control of water ingress, etc., in cargo ships [only] – [Ref. SLF 51/3/2, also

Regulation 25 ………...Water level detectors on single hold cargo ships other than bulk

carriers

Part C – Machinery installations

Regulation 35-1 ...Bilge Pumping Arrangements

Adoption of Amendments to the International Convention for the Safety of Life at Sea, 1974, as amended

(Ref. Resolution MSC.216(82), adopted on 8th _{October, 2006)}

Recommendation on a Standard Method for Evaluating Cross-Flooding Arrangements (Ref. Resolution MSC.245(83), adopted on 12th _{October, 2007)}

Adoption of Amendments to the International Convention for the Safety of Life at Sea, 1974, as amended

(Ref. Resolution MSC.269(85), adopted on 4th December, 2008)

[Amendments not included in SOLAS Consolidated Edition 2009 but highlighted thus in this document] Explanatory Notes to the SOLAS Chapter II-1 Subdivision and Damage Stability Regulations

Associated MSC Circulars included in the text below for easy reference

Guidance Notes on the Integrity of Flooding Boundaries above the Bulkhead Deck of Passenger Ships

(Ref. MSC/Circ.541, dated 19th _{July, 1990)}

Unified Interpretation regarding Timber Deck Cargo in the Context of Damage Stability Requirements

(Ref. MSC/Circ.998, dated 25th _{July, 2001)}

Unified Interpretations to SOLAS II-1 Part B-1 Regulation 5 regarding Stability Information for Passenger and Cargo Ships (Lightweight Check)

(Ref. MSC/Circ.1158, dated 24th _{May, 2005)}

Unified Interpretations to SOLAS Chapter II-1 Regulation12 regarding Bow Doors and the Extension of the Collision Bulkhead.

(Ref. MSC.1/Circ.1211, dated 25th _{May, 2006)}

Performance Standards for the Systems and Services to Remain Operational on Passenger Ships for Safe Return to Port and Orderly Evacuation and Abandonment after a Casualty

(Ref. MSC.1/Circ.1214, dated 15th _{December, 2006)}

Guidelines for Damage Control Plans and Information to the Master. (Ref. MSC.1/Circ.1245, dated 29th October, 2007)

Interpretation of Alterations and Modifications of a Major Character

(Ref. MSC.1/Circ.1246, dated 29th _{October, 2007, which supersedes MSC/Circ.650).} Guidelines for Flooding Detection Systems on Passenger Ships.

(Ref. MSC.1/Circ.1291, adopted on 9th _{December, 2008)}

Guidelines for the Drainage of Fire-Fighting Water from Closed Vehicle and Ro-Ro Spaces and Special Category Spaces of Passenger and Cargo Ships.

(Ref. MSC.1/Circ.1320, dated 11th _{June, 2009)}

Guidance for watertight doors on passenger ships which may be opened during navigation.

RESOLUTION MSC.281(85) (adopted on 4 December 2008)

EXPLANATORY NOTES TO THE SOLAS CHAPER II-1 SUBDIVISION AND DAMAGE STABILITY REGULATIONS

THE MARITIME SAFETY COMMITTEE,

RECALLING Article 28(b) of the Convention on the International Maritime Organization concerning the function of the Committee,

RECALLING ALSO that, by resolution MSC.216(82), it adopted the regulations on subdivision and damage stability as contained in SOLAS chapter II-1 which are based on the probabilistic concept, using the probability if survival after collision as a measure of ships’ safety in a damage condition,

NOTING that, at the eighty-second session, it approved Interim Explanatory Notes to the SOLAS chapter II-1 subdivision and damage stability regulations (MSC.1/Circ.1226), to assist Administrations in the uniform interpretation and application of the aforementioned subdivision and damage stability regulations.

BEING DESIROUS that definitive Explanatory Notes should be adopted when more experience in the application of the aforementioned subdivision and damage stability regulations and the Interim Explanatory Notes had been gained,

RECOGNIZING that the appropriate application of the Explanatory Notes is essential for ensuring the uniform application of the SOLAS chapter II-1 subdivision and damage stabilioty regulations,

HAVING CONSIDERED, at its eighty-fifth session, the recommendations made by the Sub-Committee on Stability and Load Lines and on Fishing Vessels Safety at its fifty-first session,

1. ADOPTS the Explanatory Notes to the SOLAS chapter II-1 subdivision and damage stability regulations set out in the Annex to the present resolution;

2. URGES Governments and all parties concerned to utilize the Explanatory Notes when applying the SOLAS chapter II-1 subdivision and damage stability regulations adopted by resolution MSC.216(82).

EXPLANATORY NOTES TO THE SOLAS CHAPTER II-1

SUBDIVISION AND DAMAGE STABILITY REGULATIONS

Contents

Part A - INTRODUCTION

Part B - GUIDANCE ON INDIVIDUAL SOLAS CHAPTER II-1 SUBDIVISION

AND DAMAGE STABILITY REGULATIONS

Regulation 1 Application

Regulation 2 Definitions

Regulation 4 General

Regulation 5 Intact stability information

Regulation 5-1 Stability information to be supplied to the master

Regulation 6 Required subdivision index R

Regulation 7 Attained subdivision index A

Regulation 7-1 Calculation of the factor pi

Regulation 7-2 Calculation of the factor si

Regulation 7-3 Permeability

Regulation 8 Special requirements concerning passenger ship stability

Regulation 8-1 System capabilities and operational information after a flooding casualty on passenger ships

Regulation 9 Double bottoms in passenger ships and cargo ships other than tankers

Regulation 10 Construction of watertight bulkheads

Regulation 12 Peak and machinery space bulkheads, shaft tunnels, etc.

Regulation 13 Openings in watertight bulkheads below the bulkhead deck in passenger

ships

Regulation 13-1 Openings in watertight bulkheads and internal decks in cargo ships

Regulation 15 Openings in the shell plating below the bulkhead deck of passenger

ships and the free board deck of cargo ships

Regulation 15-1 External openings in cargo ships

Regulation 16 Construction and initial tests of watertight doors, sidescuttles, etc.

Regulation 17 Internal watertight integrity of passenger ships above the bulkhead deck

Appendix Guidelines for the preparation of subdivision and damage stability

PART A INTRODUCTION

1 The harmonized SOLAS regulations on subdivision and damage stability, as contained in revised SOLAS chapter II-1 are based on a probabilistic concept which uses the probability of survival after collision as a measure of ships’ safety in a damaged condition. This probability is referred to as the “attained subdivision index A” in the regulations. This can be considered an objective measure of ship safety and, ideally, there would be no need to supplement this index by any deterministic requirements. 2 The philosophy behind the probabilistic concept is that two different ships with the same attained index are of equal safety and, therefore, there is no need for special treatment of specific parts of the ship, even if they are able to survive different damages. The only areas which are given special attention in these regulations are the forward and bottom regions which are dealt with by special subdivision rules provided for the cases of ramming and grounding.

3 Only a few deterministic elements, which were necessary to make the concept practicable, have been included. It was also necessary to include a deterministic “minor damage” on top of the probabilistic regulations for passenger ships to avoid ships being designed with what might be perceived as unacceptably vulnerable spots in some part of their length.

4 It is easily recognized that there are many factors that will affect the final consequences of hull damage to the ship. These factors are random and their influence is different for ships with different characteristics. For example, it would seem obvious that in ships of similar size carrying different amounts of cargo, damages of similar extents may lead to different results because of differences in the range of permeability and draught during service. The mass and velocity of the ramming ship is obviously another random variable.

5 Due to this, the effect of a three-dimensional damage to a ship with given watertight subdivision depends on the following circumstances:

.1 which particular space or group of adjacent spaces is flooded;

.2 the draught, trim and intact metacentric height at the time of damage; .3 the permeability of affected spaces at the time of damage;

.4 the sea state at the time of damage; and

.5 other factors, such as possible heeling moments due to unsymmetrical weights.

6 Some of these circumstances are interdependent and the relationship between them and their effects may vary in different cases. Additionally, the effect of hull strength on penetration will obviously have some effect on the results for a given ship. Since the location and size of the damage is random, it is not possible to state which part of the

ship becomes flooded. However, the probability of flooding a given space can be determined if the probability of occurrence of certain damages is known from experience, that is, damage statistics. The probability of flooding a space is then equal to the probability of occurrence of all such damages which just open the considered space to the sea.

7 For these reasons and because of mathematical complexity as well as insufficient data, it would not be practicable to make an exact or direct assessment of their effect on the probability that a particular ship will survive a random damage if it occurs. However, accepting some approximations or qualitative judgments, a logical treatment may be achieved by using the probability approach as the basis of a comparative method for the assessment and regulation of ship safety.

8 It may be demonstrated by means of probability theory that the probability of ship survival should be calculated as a sum of probabilities of its survival after flooding each single compartment, each group of two, three, etc., adjacent compartments multiplied, respectively, by the probabilities of occurrence of such damages as lead to the flooding of the corresponding compartment or group of compartments.

9 If the probability of occurrence for each of the damage scenarios the ship could be subjected to is calculated and then combined with the probability of surviving each of these damages with the ship loaded in the most probable loading conditions, we can determine the attained index A as a measure for the ship’s ability to sustain a collision damage.

10 It follows that the probability that a ship will remain afloat without sinking or capsizing as a result of an arbitrary collision in a given longitudinal position can be broken down to:

.1 the probability that the longitudinal centre of damage occurs in just the region of the ship under consideration;

.2 the probability that this damage has a longitudinal extent that only includes spaces between the transverse watertight bulkheads found in this region;

.3 the probability that the damage has a vertical extent that will flood only the spaces below a given horizontal boundary, such as a watertight deck; .4 the probability that the damage has a transverse penetration not greater

than the distance to a given longitudinal boundary; and

.5 the probability that the watertight integrity and the stability throughout the flooding sequence is sufficient to avoid capsizing or sinking.

11 The first three of these factors are solely dependent on the watertight arrangement of the ship, while the last two depend on the ship’s shape. The last factor also depends on the actual loading condition. By grouping these probabilities, calculation of the probability of survival, or attained index A, have been formulated to include the following probabilities:

.1 the probability of flooding each single compartment and each possible group of two or more adjacent compartments; and

.2 the probability that the stability after flooding a compartment or a group of two or more adjacent compartments will be sufficient to prevent capsizing or dangerous heeling due to loss of stability or to heeling moments in intermediate or final stages of flooding.

12 This concept allows a rule requirement to be applied by requiring a minimum value of A for a particular ship. This minimum value is referred to as the “required subdivision index R” in the present regulations and can be made dependent on ship size, number of passengers or other factors legislators might consider important.

13 Evidence of compliance with the rules then simply becomes:

A ≥ R

As explained above, the attained subdivision index A is determined by a formula for the entire probability as the sum of the products for each compartment or group of compartments of the probability that a space is flooded, multiplied by the probability that the ship will not capsize or sink due to flooding of the considered space. In other words, the general formula for the attained index can be given in the form:

A = Σpi.si

Subscript “i” represents the damage zone (group of compartments) under consideration within the watertight subdivision of the ship. The subdivision is viewed in the longitudinal direction, starting with the aftmost zone/compartment.

The value of “pi” represents the probability that only the zone “i” under consideration will be flooded, disregarding any horizontal subdivision, but taking transverse subdivision into account. Longitudinal subdivision within the zone will result in additional flooding scenarios, each with their own probability of occurrence.

The value of “si” represents the probability of survival after flooding the zone “i” under consideration.

14 Although the ideas outlined above are very simple, their practical application in an exact manner would give rise to several difficulties if a mathematically perfect method was to be developed. As pointed out above, an extensive but still incomplete description of the damage will include its longitudinal and vertical location as well as its longitudinal, vertical and transverse extent. Apart from the difficulties in handling such a five-dimensional random variable, it is impossible to determine its probability distribution very accurately with the presently available damage statistics. Similar limitations are true for the variables and physical relationships involved in the calculation of the probability that a ship will not capsize or sink during intermediate stages or in the final stage of flooding. 15 A close approximation of the available statistics would result in extremely numerous and complicated computations. In order to make the concept practicable, extensive simplifications are necessary. Although it is not possible to calculate the exact probability of survival on such a simplified basis, it has still been possible to develop a useful comparative measure of the merits of the longitudinal, transverse and horizontal subdivision of the ship.

RESOLUTION MSC.216(82) (adopted on 8 December 2006)

ADOPTION OF AMENDMENTS TO THE INTERNATIONAL CONVENTION FOR THE SAFETY OF LIFE AT SEA, 1974, AS AMENDED

THE MARITIME SAFETY COMMITTEE,

RECALLING Article 28(b) of the Convention on the International Maritime Organization concerning the functions of the Committee,

RECALLING FURTHER article VIII(b) of the International Convention for the Safety of Life at Sea (SOLAS), 1974 (hereinafter referred to as “the Convention”), concerning the amendment procedure applicable to the Annex to the Convention, other than to the provisions of chapter I thereof,

HAVING CONSIDERED, at its eighty-second session, amendments to the Convention, proposed and circulated in accordance with article VIII(b)(i) thereof,

1. ADOPTS, in accordance with article VIII(b)(iv) of the Convention, amendments to the Convention, the text of which is set out in Annexes 1, 2 and 3 to the present resolution;

2. DETERMINES, in accordance with article VIII(b)(vi)(2)(bb) of the Convention, that:

(a) the said amendments, set out in Annex 1, shall be deemed to have been accepted on 1 January 2008;

(b) the said amendments, set out in Annex 2, shall be deemed to have been accepted on 1 July 2008; and

(c) the said amendments, set out in Annex 3, shall be deemed to have been accepted on 1 January 2010,

unless, prior to those dates, more than one third of the Contracting Governments to the Convention or Contracting Governments the combined merchant fleets of which constitute not less than 50% of the gross tonnage of the world’s merchant fleet, have notified their objections to the amendments;

3. INVITES SOLAS Contracting Governments to note that, in accordance with article VIII(b)(vii)(2) of the Convention:

(b) the amendments, set out in Annex 2, shall enter into force on 1 January 2009; and

(c) the amendments, set out in Annex 3, shall enter into force on 1 July 2010, upon their acceptance in accordance with paragraph 2 above;

4. REQUESTS the Secretary-General, in conformity with article VIII(b)(v) of the Convention, to transmit certified copies of the present resolution and the text of the amendments contained in Annexes 1, 2 and 3 to all Contracting Governments to the Convention;

5. FURTHER REQUESTS the Secretary-General to transmit copies of this resolution and its Annexes 1, 2 and 3 to Members of the Organization, which are not Contracting Governments to the Convention.

ANNEX 2

AMENDMENTS TO THE INTERNATIONAL CONVENTION FOR THE SAFETY OF LIFE AT SEA, 1974, AS AMENDED

CHAPTER II-1

CONSTRUCTION -STRUCTURE, SUBDIVISION AND STABILITY,

MACHINERY AND ELECTRICAL INSTALLATIONS

The existing text of parts A, B and B-1 of the chapter is replaced by the following:

(Extracts from SOLAS Consolidated Edition 2009)

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 January 2009.

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 one per cent 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

January 2009;

.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;

.4 the expression alterations and modifications of a major character means, in the context of cargo ship subdivision and stability, any modification to the construction which affects the level of subdivision of that ship. Where a cargo ship is subject to such modification, it shall be demonstrated that the A/R ratio calculated for the ship after such modifications is not less than the A/R ratio calculated for the ship before the modification.

However, in those cases where the ship’s A/R ratio before modification is equal to or greater than unity, it is only necessary that the ship after modification has an A value which is not less than R, calculated for the modified ship. [Q1]

Regulation 1.1.3.4 (ref. SLF 51/3/2 – US and Sweden)

This provision, regarding cargo ship subdivision and damage stability in the context of alterations and modifications of a major character, is not currently in line with the principles recently agreed to at SLF 50 and approved at MSC 83 in new MSC.1/Circ.1246 (which superseded MSC/Circ.650). This provision should be revised to reflect the principles in MSC.1/Circ.1246 (see SLF 50/19, paragraph 3.17.2) [Coordinator’s Note: MSC.1/Circ.1246 is included below for easy reference].

Regulation 1.1.3.4 (ref. SLF 52/17/5 - Norway)

Document SLF 51/3/2 contains a proposal that the paragraph should be revised to reflect the principles in MSC.1/Circ.1246.

This Administration agrees that a revision is appropriate. The intended application of paragraph 1.3.4 appears to be unclear. Any ship constructed from 1 January 2009 onwards must comply fully with the revised chapter according to its type and length at all times, not just an A/R evaluation. All older ships are still subject to compliance with regulations 1.3.1 in the previous version of chapter II-1 (and MSC.1/Circ.1246 if adopted by the Administration).

In this chapter the expression “major character” is only used for a very limited purpose in paragraph 3. Paragraph 2 on new regulation 1 lists applicable standards for ships constructed before 1 January 2009. Since the damage stability requirements in resolutions MSC.19(58) and MSC.47(66) are included in that list, it would seem inappropriate to apply the provisions of the new chapter in cases where an existing ship continues to comply fully with those provisions after a conversion.

For the time being it seems that the only contingency needed in paragraph 1.3.4 with respect to stability is where a dry cargo ship of less than 80 m in length (L) is lengthened beyond that limit. It is proposed that the application of MSC.1/Circ.1246 is limited to ships constructed before 1 January 2009 and that a separate circular be developed to cover ships constructed from 1 January 2009 onwards.

It is also proposed that a footnote with reference to MSC.1/Circ.1246 be added to paragraph 3 to cover existing ships.

R1.3.4 Alterations and modifications of a major character R1.3

Q1. Norway suggests that Regulation 1.3.4 is currently unclear in its application; the only situation it needs to cover is when a S2009 cargo ship is lengthened beyond 80 m(L). Norway proposes that a new MSC Circular is needed for ships constructed after 1/1/2009 and that MSC.1/Circ.1246 should only apply to existing ships built before 1/1/2009. A footnote should be added to Regulation 1.3 stating that for ships constructed before 1/1/2009 MSC.1/Circ.1246 should be applied. Do you agree with these proposals?

Yes China, Finland, Germany, Japan, MI, Norway, Italy, Spain, Denmark, UK, US, Sweden

No

Comments / Alternative Proposals / Suggested wording for footnote?:-

US: We fully agree with the principles associated with Norway’s proposals. However, we think it would be better to delete regulation 1.1.3.4 completely. This is because for cargo ships built on or after 1 January 2009 there should not be an A/R standard applied (i.e. “Any ship constructed from 1 January 2009 onwards must comply fully with the revised chapter according to its type and length at all times, not just an A/R evaluation.”). This reflects the same principle applied in MSC.1/Circ.1246 (i.e. if constructed on or after 1 July 1998 the ship is never considered an ‘existing cargo ship’).

If regulation 1.1.3.4 is deleted, the existing EN for regulation 1.3 (now only addressing passenger ships) could be expanded to indicate:

• Application of MSC.1/Circ.1246 is limited to cargo ships constructed before 1 January 2009. • a cargo ship constructed on or after 1 January 2009 of less than 80 m in length that is later

lengthened beyond that limit must fully comply with the damage stability regulations according to its type and length.

Note: this should also eliminate the need for a footnote regarding MSC.1/Circ.1246.

Round 1 Discussion: Although there is strong support for Norway’s proposal it would seem that the US’ suggestions may provide the best solution.

Q1A. Recognising that Reg. 1.1.3.4 may be misleading do you support the US proposal to delete it altogether and change EN 1.3 as highlighted below?:- Regulation 1.3

.1 If a passenger ship built before 1 January 2009 undergoes alterations or modifications of major character, it may still remain under the damage stability regulations applicable to ships built before 1 January 2009, except in the case of a cargo ship being converted to a passenger ship.

.2 Application of MSC.1/Circ.1246 is limited to cargo ships constructed before 1 January 2009

.3 A cargo ship constructed on or after 1 January 2009 of less than 80 m in length that is later lengthened beyond that limit must fully comply with the damage stability regulations according to its type and length.

Yes MI, Germany, China, Finland, US, Italy, Japan, RINA (see comment 1), France (with comment), Norway, CLIA, UK, Denmark

No RINA (see comment 2), Sweden Comments / Alternative Proposals?:-

MI: Agree deletion of Reg. 1.1.3.4 and change EN 1.3 as proposed by the US.

RINA: 1. We would support the deletion of 1.1.3.4 as the definitions to alteration and modifications of a major character for cargo and passenger ships are included in regulation 1.3. 2. With regard to the proposal to amend EN 1.3 we would comment as follows:

• 1.3.1 The inclusion of this text conflicts with that in Regulation 1.3. The A/R ratio calculated for the ship after modifications is not less than the A/R ratio calculated for the ship before the modification, is in general, applicable to ships which have their

damage stability assessed in accordance with a deterministic method. It would then follow that all such ships, when modified, should meet the requirements of MSC.1/Circ.1246.

• 1.3.2 If the rationale in 1.3.1 is accepted then MSC.1/Circ.1246 will need to be revised to address alteration and modifications of a major character for passenger and cargo ships which have been assessed against deterministic damage stability calculations. France: US proposal is in line with present explanatory notes.

Round 2 Discussion: Although there is a large majority in support of the US proposal to delete regulation 1.1.3.4 and expand EN 1.3, Sweden is opposed and RINA has doubts about the amendments to the EN.

Regarding RINA’s comments - our understanding of MSC.1/Circ.1246 is that it was written to cover the situation where a cargo ship built before damage stability regulations were introduced into SOLAS90 Part B-1 on 1st _{February, 1992 underwent major alterations. Prior to that date} cargo ships were not required to comply with any damage stability standards (except ILLC, Reg. 27) so we cannot agree with the RINA statement that such ships would necessarily have had their damage stability assessed against a deterministic standard. For this reason Circ.1246 is specifically addressing cargo ships only and requires new calculations of A/R to be carried out “before and after” major modification to ensure that whatever safety level the vessel had beforehand was either not reduced (if A was <=R) or become less than one (if A was > R). We therefore believe that the proposed amendments to the EN do make sense as written.

Q1B (for SLF53 WG). Can we accept the US proposal to delete Part A Reg. 1.1.3.4 and amend EN 1.3 as shown under Q1A (above)?

Yes Proposal accepted by SLF53 WG

No

Are there any further comments?:- No further discussion in 2011 CG.

Q1. Recommend acceptance at SLF54

Ref. T1/2.04 MSC.1/Circ.1246

29 October 2007 INTERPRETATION OF ALTERATIONS AND MODIFICATIONS OF A MAJOR

CHARACTER

1. The Maritime Safety Committee, at its sixty-third session (16-25 May 1994), noted that the Sub-Committee on Stability and Load Lines and on Fishing Vessels Safety (SLF), in considering a definition of the term “modification of a major character” in the context of Chapter II-1 of the 1974 SOLAS Convention, had decided that it should be sufficient to relate the modification, whatever its nature and extent, to its effect on the level of subdivision of the ship. The Committee, therefore, agreed to the following interpretation of alterations and modifications of a major character proposed by the SLF Sub-Committee:

. “Where an existing cargo ship is subject to any modification which affects the level of subdivision of that ship, it should be demonstrated that the A/R ratio calculated for the ship after such modifications is not less than the A/R ratio calculated for the ship before the modification. However, in those cases where the ship’s A/R ratio before modification is equal to or greater than unity, it is only necessary to demonstrate that the ship after such modification has an ’A’ value which is not less than ’R’, calculated for the modified ship.”

2. The Maritime Safety Committee, at its eighty-third session (3-12 October 2007), considered a definition of the term “existing cargo ship” in the context of the above interpretation and, following a proposal by the SLF Sub-Committee at its fiftieth session, agreed that, in the context of this circular, an existing cargo ship means:

.1. a cargo ship constructed before 1 February 1992, regardless of length; and .2. a cargo ship constructed before 1 July 1998, below or equal to 100 m in length. 3. Notwithstanding the above, a cargo ship should not be considered an existing cargo ship if it was:

.1 constructed between 1 February 1992 and 30 June 1998, and lengthened from below to above 100 m; and

.2 constructed on or after 1 July 1998.

4. Member Governments are invited to take account of the above interpretation when applying the relevant provisions of Chapter II-1 of the 1974 SOLAS Convention.

5. This circular supersedes MSC/Circ.650

2 Unless expressly provided otherwise, for ships constructed before 1 January 2009, 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 resolutions MSC.1(XLV), MSC.6(48), MSC.11(55), MSC.12(56), MSC.13(57), MSC.19(58), MSC.26(60), MSC.27(61), Resolution 1 of the 1995 SOLAS Conference, MSC.47(66), MSC.57(67), MSC.65(68), MSC.69(69), MSC.99(73), MSC.134(76), MSC.151(78) and MSC.170(79) are complied with.

3 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 the date on which any relevant amendments enter into force, 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 the date on which any relevant amendments enter into force, in so far as the Administration deems reasonable and practicable.

Regulation 1.3

modifications of major character, it may still remain under the damage stability regulations applicable to ships built before 1 January 2009, except in the case of a cargo ship being converted to a passenger ship.

.2 Application of MSC.1/Circ.1246 is limited to cargo ships constructed before 1 January 2009

.3 A cargo ship constructed on or after 1 January 2009 of less than 80 m in length that is later lengthened beyond that limit must fully comply with the damage stability regulations according to its type and length

. [Co-ordinator’s Note: See Q1B for a proposal to modify this EN, which was accepted by

the WG at SLF 53]

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 fly 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 Subdivision length (L_s) of the ship is the greatest projected moulded length of

that part of the ship at or below deck or decks limiting the vertical extent of flooding with the ship at the deepest subdivision draught.

Regulation 2.1

Subdivision length (L_s) – Different examples of L_s showing the buoyant hull and the reserve buoyancy are provided in the figures below. The limiting deck for the reserve buoyancy may be partially watertight.

The maximum possible vertical extent of damage above the baseline is ds + 12.5 metres.

2 Mid-length is the mid-point of the subdivision length of the ship.

[

]

[

There was an 11-1 majority in favour – to be finally agreed at SLF 54.]

2 Amidship is at the middle of the length (L). [Proposal to move Reg. 2.26 to Reg.

2.2 to replace deleted definition of “mid length”.] [Q66 – see under 2.26, below] 3 2 Aft terminal is the aft limit of the subdivision length.

4 3 Forward terminal is the forward limit of the subdivision length.

5 4 Length (L) is the length as defined in the International Convention on Load Lines

in force.

6 5 Freeboard deck is the deck as defined in the International Convention on Load

Lines in force. Regulation 2.6 2.5

Freeboard deck – See Explanatory Notes for regulation 13-1* for the treatment of a stepped freeboard deck with regard to watertightness and construction requirements.

* References to regulations in these Guidelines are to regulations of SOLAS chapter II-1, unless expressly provided otherwise.

7 6 Forward perpendicular is the forward perpendicular as defined in the

International Convention on Load Lines in force.

8 7 Breadth (B) is the greatest moulded breadth of the ship at or below the deepest

subdivision draught.

9 8 Draught (d) is the vertical distance from the keel line at mid-length amidships

[Q2] to the waterline in question.

Regulation 2.9 (ref. SLF 52/17/6 - Norway)

The definition of draught was transferred from the previous chapter. Since the calculations in old part B-1 were to be carried out at even keel the longitudinal position of “mid-length” had no practical implication, but this is no longer the case. The revised chapter requires that additional calculations must be carried out at d_s and d_p if the anticipated operational trim range exceeds +/-0.5% of L_s.

According to its definition the aft terminal of the subdivision length L_s can be located a substantial distance aft of the aft perpendicular according to the load line length (L) and the aft terminal of the conventional length between perpendiculars (LBP) often preferred by yards and designers. The latter is normally referred to in the ship’s hydrostatic particulars. As a result the mid-length draught at L_s will often differ from the draught at the load line mark and from the longitudinal reference point assumed in the stability manual for trimmed waterlines. The nominal value of a trim measured over L_s will then also differ from the trims assumed in the stability booklet. This inconsistency should be rectified.

other contexts where consistency with intact stability calculations is important. Since practices on the definitions of LBP may vary it is proposed as a compromise that “draught” in the regulations is referred to length (L) in the future by amending paragraphs 9 and 13 as follows:

Draught (d) is the vertical distance from the keel line at mid-length on length (L) to

the waterline in question.

R2.2 Definition of mid-length R2.9 Definition of draught

Q2. Do you agree with the underlined addition to the definition of draught? Yes Japan, MI, Norway, Spain, Denmark, US, Sweden

No China, Finland, Germany, CLIA, Italy, UK Comments / Alternative Proposals?:-

China: Regarding definition of draught: The draught (dl, dp and ds) used in the calculation of Index A should be the same for all trims. Mean draught cannot achieve this. However, correspondent draft (i.e. the draught corresponding to level trim) under a constant displacement doesn’t vary with the floating status. Therefore China proposes to revise paragraph 9 as follows:

“9 draught (d) is the vertical distance from the keel line to the waterline at level trim.”

This revision implies that 3 draughts (dl, dp and ds) defined in paragraph 10, 11 and 12 should be determined at level trim. And this also can resolve the problems mentioned by Norway.

Finland: Prefer to add “on length (LBP)” to avoid differences between Ls and L (Load Line). All stability documents are done to refer length between perpendiculars including also input data in stability loading computer. Clear definition of LBP is needed to insert under reg. 2.

Germany: We prefer that “LBP” (length between perpendiculars) shall be used as this is a preferable approach to address this important information to the crew and to ensure “operational compliance”. At the same time a clear definition of LBP is needed.

CLIA:No need. Lg is OK!

Italy: Length between perpendiculars “LBP” is preferable for operational purpose. Spain: We can accept the proposal, but, in that case we think that more modifications (as

proposed in other parts of this document) are needed. We think that all of these changes should be evaluated jointly:

- Regulation 2.2 (Mid-length definition) should be deleted or changed.

- The trim definition and the limits should be adjusted also (according proposal contained in Q3):

Clarification: In S2009 trim is the difference between the draught forward and the draught aft, where the draughts are measured at the forward and aft terminals

respectively, disregarding any rake of keel. If the draught definition is changed, then the new draught is the vertical distance at mid-length on length (L), but it is not equal to the average of draught forward and the draught aft, measured at the forward and aft

terminals. In other words, d ≠ Aft/Fore draught ± Trim / 2. That is why we agree with proposal of Norway (see Q3).

- To be consequent, trim limits should be changed accordingly. It should be referred to +/-0.5% of L (instead of Ls).

- As per Norway proposal (SLF 52/17/6), for consistency Ls should then be replaced by the load line length L in other regulations.

US: However, isn’t the mid-length of L already defined as “amidships”? Suggest changing to: “Draught (d) is the vertical distance from the keel line at amidships to the waterline in question.” Also, not sure if the definition of “mid-length” is now needed; is it used anywhere other than in the definition of draught?

Round 1 Discussion: The current definition of draught (d) is that it is the vertical distance from the keel line at mid-length (defined in Reg 2.2 as the mid-point of the subdivision length, Ls) to the waterline in question. Norway is concerned that there may be some confusion between the draughts and trims used in the damage stability calculations and those in the intact stability as used in the Stability Book. The aft terminal on Ls can differ considerably from the AP on L or LBP. Norway proposes to solve this by specifying that draught “d” be measured at the mid-length “on length (L)”. For consistency they propose a similar amendment in the definition of trim (Reg. 2.13 – see Q3).

A problem with Norway’s proposal is that the term “mid-length” is already defined in 2.2 relative to Ls. The current trim definition refers to the aft and forward terminals, also relative to Ls. So “mid-length” referring to L, as proposed, could be confusing. The US suggests that there is already a definition for amidships at the middle of the length (L) (See Reg. 2.26) and proposes to use this in a new definition (above). Spain and the US question whether the Reg. 2.2 definition of mid-length is needed at all.

China tries to avoid the problem by removing all references to amidships or mid-length but there may be a problem here with rake of keel vessels where the midships reference point for draught needs to be defined.

Several correspondents express a preference for use of LBP. If LBP is the same as L (is there a difference?) and we use the US proposal then it seems we could reach agreement. The remaining question then would be whether to remove Reg 2.2 altogether and re-number the remaining regulations or just leave it there serving no purpose.

Q2A. Recognising that Norway has identified a possible source of confusion over the definition of draught in Reg 2.9 and also that we need consistency throughout in the use of L and Ls, can we accept the US’ proposed revision of 2.9 as follows?:-

“Draught (d) is the vertical distance from the keel line at amidships to the waterline in question.”

Yes MI, US, Japan, RINA, Norway (but with comment), CLIA, UK (with comment), Sweden

No Germany, Finland (with comment), Italy (with comment), France (with _{comments), Denmark}

Comments / If “Yes” should we delete existing regulation 2.2 which is not used anywhere else and re-number the remaining regulations (cross-referencing checks will be needed) / Alternatives?

MI: Agree (to delete Reg 2.2 etc ).

Germany: No, we still prefer LBP and the corresponding trim and draft.

China: Draught at amidships equals to mean draft which may be have multiple value as it varies with trim. In order not produce multiple draught, correspondent draught, or draught at LCF, of ds, dp and dl should be used in damage stability calculation. Therefore China would like to suggest a slight change to the wording proposed by US as follows:

amidships to the waterline in question.”

Finland: All delivery documents (draught and trim) related to stability are based on LBP. Also software in loading computers is based on LBP. Crew are familiar with LBP (between perpendiculars).

US: Yes [delete Reg. 2.2 and renumber the rest].

Italy: LBP is preferred. Stability manuals are referring to LBP, which is not the same as L (which is defined in the Load Line Convention).

RINA: Agree that regulation 2.2 could be deleted.

France: A common reference must be used for all stability documents. When ship is trimmed, draft will be different depending on mid-length definition, for a given waterline, but this will not influence calculation results. So France proposes to measure the draft at mid length between design perpendiculars which seems to be the current practice.

A way may be to modify reg 2.2 and 2.9 as follows :

2 Reference point is the mid-point of design length between points where are calculated fore and aft drafts reported in stability documents.

9 Draught (d) is the vertical distance from the keel line at reference point to the waterline in question.

Norway: Yes, but 2.2 should rather be harmonized with ICLL-66, i.e. “Amidships is the middle of the length (L)”. The mean draught will then be measured in the same longitudinal location as the load line mark. Our proposal was based on the anticipation that it may prove difficult to agree on a universal definition of LBP that will be enforceable due to different local traditions and practices on designer level.

UK: The use of “mid-length” was needed for the old regulations where the assumed distribution density of damage location centre was not uniform, whereas the harmonised regulations assumed that the factor “a” to be uniformly distributed, therefore this definition is no longer needed. Should the above said distribution function be modified in the future to account for historical changes to come, there is no guarantee that “mid-length” to mark a bi-linear function might be employed.

Round 2 Discussion: It seems that the UK has provided us with a very good reason to delete Reg. 2.2. China’s proposal to define “d” as draught at LCF (correspondent draught) would seem to be difficult to apply as LCF varies with draught – but perhaps we have not understood the proposal correctly? We also don’t quite understand Norway’s comment as the definition they quote - “Amidships is the middle of the length (L)” – is already included as Reg. 2.26.

Several members still prefer to use “LBP” rather than “L”. It seems that we could probably all agree to the US proposal - “Draught (d) is the vertical distance from the keel line at amidships to the waterline in question.” – with amidships as defined in Reg. 2.26 and with Reg. 2.2 deleted if only we could agree that “LBP” and “L” are the same.

The advantage of using “L” from the ICLL is that it is very clearly defined, with diagrams and explanations, even covering raked keel vessels (ref. Res. MSC.143(77) Reg. 3) . We have already referred the definition of forward perpendicular (Reg. 2.7) to the ICLL definition and our definition of amidships in Reg. 2.26 is the same as in the ICLL. The ICLL definition of “perpendiculars” (Ref. MSC.143 reg. 3.2) reads:-

“The forward and after perpendiculars shall be taken at the forward and after ends of the length (L). The forward perpendicular shall coincide with the foreside of the stem on the waterline on

which the length is measured.”

We don’t really understand why, as Italy and many others state, “Stability manuals are referring

to LBP, which is not the same as L (which is defined in the Load Line Convention).” Maybe it is

something to do with the A.P. definition – azipods, for example? Perhaps we should discuss this at SLF 53 and if we cannot agree that L is the same as LBP we may need to revise the definitions of Regs. 2.2 and 2.9 as proposed by France.

Q2B (for SLF53 WG). Can we agree that L as defined in ICLL is the same as LBP as commonly used in industry? Consistency needed with Reg. 2.13 on trim (see Q3).

Yes No

Comments / If “yes” can we then agree to the US’ proposed revision of Reg. 2.9, the deletion of Reg. 2.2 and the consequent re-numbering of Regs. 2.3 to 2.26? / Alternatives?

After discussion, the US’ proposals were agreed to by the SLF 53 WG.

Q2. Recommend acceptance at SLF54 but the re-numbering may not be necessary (see Q66).

10 9 Deepest subdivision draught (d_s) is the waterline which corresponds to the

summer load line draught of the ship.

11 10 Light service draught (d_l) is the service draught corresponding to the lightest

anticipated loading and associated tankage, including, however, such ballast as may be necessary for stability and/or immersion. Passenger ships should include the full complement of passengers and crew on board. [Coordinator’s Note:- New question for SLF53 WG: For ro-pax ships do we include full passengers but no cars? It does not seem logical as most ro-ro passengers come with their cars.] [Coordinator’s Note post SLF 53 – we can’t recall what was decided in WG3 – therefore guess that no clarification is necessary].

Regulation 2.11 2.10

Light service draught (dl) – The light service draught (dl) represents the lower draught limit of the minimum required GM (or maximum allowable KG) curve. It corresponds, in general, to the ballast arrival condition with 10% consumables for cargo ships. For passenger ships, it corresponds, in general, to the arrival condition with 10% consumables, a full complement of passengers and crew and their effects, and ballast as necessary for stability and trim. The 10% arrival condition is not necessarily the specific condition that must be used for all ships, but represents, in general, a suitable lower limit for all loading conditions. This is understood to not include docking conditions or other non-voyage conditions.

R2.11 EN

Comments received from CLIA/CCSF between round 1 and 2:

During ballast water exchange procedures it might happen that the resulting draught will be lower than the light service draught dl. It should be made clear that such temporary conditions are not to be used for the definition of the light service draught.

Additional explanation:

Any conditions, which result to a lower draught as the 10% arrival conditions due to ballast water exchange procedures, are not to be taken as dl

Coordinator’s Comments: If we accept this addition to the EN, we would suggest slight improvements to the wording for clarity:-

Any conditions, which result [to] [in] a [lower] draught [as] [lower than] the 10% arrival conditions due to ballast water exchange procedures, are not to be taken as dl.

CG Member’s Comments?:-

MI: No objection to this addition to the EN, concur with the co-ordinator’s re-draft. Germany: Acceptable.

China: Ballast water exchange conditions as well as any other conditions which are not a recognized typical voyage condition are never used in the damage stability calculation.

Finland: OK.

US: We can accept this addition to the EN (as improved). RINA: Supports the text proposed by the Coordinator.

France: Agreement on this addition to the EN with à wording as : “Any conditions, which result in a draught lower than the 10% arrival conditions due to ballast water exchange procedures, are not to be taken as dl.”

Norway: Support the suggestion from the coordinator. CLIA: Agree.

UK: Agreed, as coordinator’s comments.

Round 2 Discussion: All who responded agreed to this improvement to the EN as amended by the co-ordinators. So Reg. 2.11 EN would now read as follows:-

Regulation 2.11

Light service draught (dl) – The light service draught (dl) represents the lower draught limit of the minimum required GM (or maximum allowable KG) curve. It corresponds, in general, to the ballast arrival condition with 10% consumables for cargo ships. For passenger ships, it corresponds, in general, to the arrival condition with 10% consumables, a full complement of passengers and crew and their effects, and ballast as necessary for stability and trim. The 10% arrival condition is not necessarily the specific condition that must be used for all ships, but represents, in general, a suitable lower limit for all loading conditions. This is understood to not include docking conditions or other non-voyage conditions. Any conditions which result in a draught lower than the 10% arrival condition due to ballast water exchange procedures are not to be taken as dl.

CONCLUDED - PROPOSAL ACCEPTED BY CG.

AWAIT APPROVAL BY SUB-COMMITTEE AT SLF 53.

(See SLF 53/14 para 12.1).

Co-ordinator’s Note post SLF 53 – although initially approved in plenary, CLIA’s proposal was not accepted following discussion in the WG and was therefore deleted in SLF 53/WP.6. However, we recall that in the WG, final resolution of the wording of Reg. 2.11 EN was to be decided when we discussed changes to Regulation 5.1. Due to time constraints this did not happen, therefore it is proposed that we re-visit this paragraph in the CG.

Co-ordinator’s Note for Round 4 Questionnaire – we will leave this question for the moment and consider it again when we look at the critical KG/GM questions (Q20 etc) in round 5.

Co-ordinator’s Note for SLF 54 – see SLF 54/8/1 para. 14.1. This EN to be reviewed in

the light of Norway’s proposed revisions (see Annex 2 of SLF 54/8/1).

12 11 Partial subdivision draught (d_p) is the light service draught plus 60% of the

13 12 Trim is the difference between the draught forward and the draught aft, where the draughts are measured at the forward and aft terminals perpendiculars respectively, as defined in the International Convention on Load Lines in force, [Q3] disregarding any rake of keel.

Regulation 2.13 (ref. SLF 52/17/6 - Norway)

Norway proposes to change 2.13 to:- [See also comments under regulation 2.9].

Trim is the difference between the draught forward and the draught aft, where the

draughts are measured at the forward and aft terminals of length (L) respectively, disregarding any rake of keel.

R2.13 Definition of Trim

Q3. Do you agree with the underlined addition to the definition? Yes Japan, MI, Norway, Italy, Spain, Denmark, US, Sweden No China, Finland, Germany, CLIA, UK

Comments / Alternative Proposals?:-

China: Definition of Trim need not be changed as trim measured based on Ls, LBP or L is not significant as the waterline is the same, the Longitudinal trim angle is also the same; the hydrostatic parameters under the waterline, such as LBP and KMT won’t be influenced by the trim definition. If the trim should be revised, the most appropriate is based on LBP.

Finland: Refer to Q2.

Germany: See comments on Q2 CLIA: No need.

Italy: See also Q2.

Spain: See comments to Q2.

An alternative text could be as follows (anyway we can accept also Norway proposal):

“Trim is the difference between the draught forward and the draught aft, where the draughts are

measured at the forward and aft perpendiculars respectively, as defined in the International Convention on Load Lines in force , disregarding any rake of keel”.

Denmark: Please note that the definitions of aft and forward terminals in Reg. 2.3 and Reg. 2.4 are based on the subdivision length.

US: Since “forward terminal” and “aft terminal” are defined terms, in this definition suggest changing to “forward and aft limits” as is used in the definition of forward/aft terminal.

Round 1 Discussion: As mentioned in the discussion for Q2, Norway’s proposal could introduce a slight inconsistency by associating “terminals” with “L”, which in 2.3 and 2.4 are defined in relation to “Ls” (as stated by Denmark & US). The US proposal of replacing “terminals” with “limits” would be more consistent but could also be slightly ambiguous as the word “limit” may not be readily associated with “L” by the user (see 2.3 and 2.4). Spain’s proposal overcomes this problem and is very specific. China’s comments are appreciated but if trim is defined as a difference in draughts measured at two reference points then those points must be defined; it is agreed that trim angle is independent of any defined reference points but is, we believe, not commonly used in stability books. There does not appear to be a definition of “trim” in the 2008 IS Code.

Q3A. Recognising that Norway has identified a possible source of confusion over the definition of trim and that there seems to be a majority in favour of defining trim over length L (or LBP) to be consistent with the stability book, do you prefer the US proposal to replace “terminals” by “limits” or the more specific proposal by Spain:-