IMO UNIFIED INTERPRETATIONS TO SOLAS CHAPTER II-2 AND RELATED FIRE TEST PROCEDURES. Comments on document FP 46/5/8. Submitted by Japan

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1 INTERNATIONAL MARITIME ORGANIZATION E IMO SUB-COMMITTEE ON FIRE PROTECTION 46th session Agenda item 5 FP 46/5/12 14 December 2001 Original: ENGLISH UNIFIED INTERPRETATIONS TO SOLAS CHAPTER II-2 AND RELATED FIRE TEST PROCEDURES Comments on document FP 46/5/8 Submitted by Japan Executive summary: Action to be taken: Paragraph 5 SUMMARY This document provides comments and opinions on document FP 46/5/8 of draft interpretations to regulations in the revised SOLAS chapter II-2. Related documents: MSC 73/21/Add.2 and FP 46/5/8 1 This document is submitted in accordance with paragraph 46.5 of the Guidelines on the organization and method of work (MSC/Circ.931) and provides supplemental comments and opinions to document FP 46/5/8 (Japan). 2 The revised SOLAS chapter II includes several new requirements for oil fuel arrangements, cargo pump rooms, fixed water-based local application fire-fighting systems and emergency escape breathing devices (EEBD). 3 In addition to the draft interpretations described by the aforementioned document, Japan thinks that interpretations on fire safety requirement to cargo pump rooms and storage rooms for fire extinguishing medium, as set out in that attached annex, are necessary, and it hopes the Sub-Committee agrees to the draft interpretations. 4 Furthermore, Japan considers it necessary to amend SOLAS Convention in the future so that the interpretations should be included in the amendments, and it suggested the draft amendments as set out in the annex. Action requested of the Sub-Committee 5 The Sub-Committee is invited to consider the above comments and the draft interpretations at annex and take action as appropriate. *** For reasons of economy, this document is printed in a limited number. Delegates are kindly asked to bring their copies to meetings and not to request additional copies.

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3 DRAFT INTERPRETATIONS OF THE REGULATIONS OF CHAPTER II-2 IN SOLAS 2000 SEPARATION OF CARGO OIL TANKS Regulation II-2/ : Cargo pump-rooms, cargo tanks, slop tanks and cofferdams shall be positioned... oil bunker tanks or ballast tanks. Pump-rooms containing pumps and their accessories for ballasting those spaces situated adjacent to cargo tanks and slop tanks and pumps for oil fuel transfer, shall be considered as equivalent to a cargo pump-room within the context of this regulation provided that such pump-rooms that have the same safety standard as that required for cargo pump-rooms. Pump-rooms intended solely for ballast or oil fuel transfer, however, need not comply with the requirements of regulation Interpretation: Pump-rooms intended solely for ballast transfer need not comply with the requirements of regulation The requirements of regulation are only applicable to the pump-rooms where pumps for cargo, such as cargo pumps, stripping pumps, pumps for slop tanks, pumps for COW, or similar pumps are provided. Reason: Refer to the appendix of this documents interpretation. for detailed reasons for the above Proposal of amendment to Reg. II-2/ in future: The 5th sentence of regulation should be amended as follows: Pump-rooms intended solely for ballast or oil fuel transfer, however, need not comply with the requirements of regulation and 10.9 STORAGE ROOMS OF FIRE EXTINGUISHING MEDIUM Regulation II-2/10.4.3: When the fire extinguishing medium is stored outside a protected space, it shall be stored. the integrity tables 9.1 to 9.8, such storage rooms shall be treated as fire control stations. Interpretation: The following requirements in the regulation are applicable only to the storage rooms of CO 2 which is the fire-extinguishing medium of fixed gas fire-extinguishing systems:.1 storage room shall be used for no other purposes (aft part of first sentence);.2 if the storage space is located below deck, it shall be located no more than one deck below the open deck and shall be directly accessible by a stairway or ladder from the open deck (3rd sentence);.3 spaces which are located below deck or spaces where access from the open deck is not provided, shall be fitted with a mechanical ventilation system designed to take exhaust air from the bottom of the space and shall be sized to provide at least 6 air changes per hour (4th sentence); and

4 Page 2.4 access doors shall open outwards, and bulkheads and decks including doors and other means of closing any opening therein, which form the boundaries between such rooms and adjacent enclosed spaces shall be gas tight (5th sentence). Reason: This requirement is located in the existing SOLAS regulation II-2/ which is applied for the fire-extinguishing medium (mainly CO 2 ) of fixed gas fire-extinguishing systems. However, when regulation was transferred to regulation of the revised SOLAS chapter II-2, it was decided that this requirement will be applied to storage rooms of all fireextinguishing mediums (e.g. CO 2, water, foam and etc.). However, the above requirements are not intended to apply to the storage rooms of fire-extinguishing medium except CO 2 for fixed gas fire-extinguishing systems. Proposal of amendment to regulation II-2/ in future Concepts of the amended regulation II-2/ are shown as follows:.1 storage rooms of the fire-extinguishing medium of fixed gas fire-extinguishing systems shall be applied to following requirements; and.2 storage rooms of all fire-extinguishing medium shall be applied to following requirements except...(except requirements of above mentioned interpretations).

5 Page 3 APPENDIX DETAILED REASON OF THE INTERPRETATION OF REGULATION II-2/ The application of the Cargo pump room safety to ballast pump rooms (Regulations and of the revised SOLAS chapter II-2) 1 The Cargo pump room safety 1.1 The requirements of regulation II-2/ in the revised SOLAS 2000 chapter II-2 (hereinafter referred to as the cargo pump-room safety ), which were introduced by the amendments adopted at MSC 73 based on MSC/Circ.774 Revised measures to prevent explosions in cargo pump-rooms of new and existing oil tankers (adopted on 12 December 1996 at MSC 67), are the safety measures for prevention of explosions in cargo pump-rooms of oil tankers and will enter into force on 1 July Requirements for ballast pump-rooms in the revised SOLAS chapter II There are many product carriers and chemical tankers which have cargo pumps installed for each cargo tanks for carrying many kind of cargoes and have a ballast pump-room arranged so as to isolate machinery spaces from cargo tanks. See the figure 1 below. Figure 1 Typical arrangement of ballast pump-room 2.2 Such ballast pump-rooms will be required to have the same safety standard as required for cargo pump-rooms in accordance with the provisions of regulation II-2/ revised from the existing regulation II-2/56.1. Regulation II-2/ (existing regulation II-2/56.1) includes the provision that ballast pump-rooms need not comply with the requirements of regulation II-2/10.9 (existing regulation II-2/63: Protection of cargo pump rooms in tankers), taking account of the provisions of MSC/Circ.847 Interpretations of vague expressions and other vague wording in SOLAS chapter II The cargo pump-room safety was discussed as an additional requirement to existing regulation II-2/63 of the requirements for fixed fire-extinguishing systems and this additional requirement to ballast pump rooms has never been discussed in the course of amendments of SOLAS chapter II-2. This fact suggests that the cargo pump-room safety will not apply to ballast pump-rooms.

6 Page 4 3 Necessity of ballast pump rooms to comply with the cargo pump-room safety 3.1 Also, from the technical point of view, the following examination does not supports the need of the application of the cargo pump-room safety requirements to ballast pump-rooms..1 An ingress of cargo to cargo pump-rooms may be caused by: (1) ingress through damaged/fractured cargo tank bulkheads; or (2) leakage from cargo pumps and cargo lines..2 An ingress of cargo to ballast pump-rooms may be caused by: (3) ingress through damaged/fractured cargo tank bulkheads and structures; or (4) leakage of cargo, which is spilled into ballast tanks through damaged/fractured cargo tank bulkheads, from ballast pumps and ballast lines. 3.2 Regarding scenarios (1) and (3) above, ingress through damaged/fractured cargo tank bulkheads may be caused by over pressure/vacuum in loading/unloading operations and/or corrosion. These issues are considered to be prevented by the secondary means of ventilation systems (regulation II-2/ ) and the enhanced survey programme respectively. Effectiveness of the requirements in regulation II-2/ is doubtful against cargo vapor from relatively small leakage. Since the cargo pump-room safety aims at preventing an ignition of cargo vapor of relatively small leakage, the application of regulation II-2/ to ballast pump-rooms on the assumption of damaged/fractured cargo tank bulkheads might not be given significant effectiveness. 3.3 Regarding to scenarios (2) and (4) above, leakage of cargo may be caused by over pressure/vacuum in loading/unloading operations and/or overage systems as same as above. However, the following difference can be shown between cargo pump-rooms and ballast pumprooms:.1 cargo pumps/lines are pressurized during cargo operations; and.2 ballast pumps/lines are pressurized only during ballast operations, and in the meantime spilled cargo into ballast tanks may be weakened by ballast sea water. 3.4 Considering the above difference and quite low probability of scenario (4) which is given by a result of cargo tank bulkheads damage and ballast pump/line leakage, ballast pump-rooms have significant smaller probability of ingress of cargo than cargo pump-rooms. 3.5 Difference of the requirements of IEC for electrical installations between cargo pump-rooms and ballast pump rooms also suggests the smaller probability of ingress of cargo into ballast pump-rooms. 4 Conclusion 4.1 In conclusion, it is not necessary to apply the cargo pump-room safety requirement to ballast pump-rooms.