IMO TEST STANDARDS FOR EXTENDED SERVICE INTERVALS OF INFLATABLE LIFERAFTS

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1 INTERNATIONAL MARITIME ORGANIZATION E IMO SUB-COMMITTEE ON FIRE PROTECTION 50th session Agenda item 16 FP 50/16 18 October 2005 Original: ENGLISH TEST STANDARDS FOR EXTENDED SERVICE INTERVALS OF INFLATABLE LIFERAFTS Proposed amendments to SOLAS chapter III, the LSA Code and resolution A.761(18) Submitted by Denmark Executive summary: Action to be taken: Paragraph 9 SUMMARY This document contains a proposed test standard for approving extended service intervals of inflatable liferafts for inclusion in resolution MSC.81(70). The document also contains proposals for ensuing amendments to SOLAS chapter III, the LSA Code and to resolution A.761(18) Related documents: MSC 78/24/10; DE 48/20/1; DE 48/25 (paragraphs 20.3 and 20.4); SOLAS III/20.8.3; the LSA Code; resolution MSC.81(70) and resolution A.761(18) Introduction 1 At the forty-eighth session of the Sub-Committee on Ship Design and Equipment, Denmark proposed (DE 48/20/1) a work plan for the development of a test standard for approving extended service intervals of inflatable liferafts. Realizing the need to base such a standard on the collection and evaluation of extensive and reliable data from seagoing vessels an extension of the target completion date of the agenda item to 2007 was proposed and accepted. 2 One of the most important factors for the justification of approval of extended service intervals for inflatable liferafts are the capabilities of the arrangement to protect the liferaft against harmful effects from the surrounding maritime environment. The arrangement will have to be capable of keeping the liferaft in a dry condition throughout the period on board a vessel, thus avoiding damaging and deterioration of fittings, fabric, seams and equipment. An approval criteria building on the presence and continued effect of a protective barrier around the liferaft itself will be obvious to introduce as a primary acceptance criteria, thus avoiding the needs of introducing complex, comparative tests with the existing liferaft concept, which in itself can result in product evaluations of subjective character. 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.

2 FP 50/ The annexes included in this document contain proposals for amending SOLAS regulation III/20.8.3, resolution A.689(17) as amended by resolution MSC.81(70) and resolution A.761(18), respectively. In order to support the understanding of the proposals, a rationale for some of the proposals which have not been found to be self-explanatory, is given in the following text. SOLAS chapter III amendments 4 Proposed amendments to SOLAS chapter III, regulation is given in annex 1. Paragraph has been changed to reflect a reference to the proposed LSA Code requirements for allowing extended service intervals. The new paragraph is proposing to limit the total period of acceptable extension of service intervals to the first 10 years of a liferafts life. This proposal is based on concerns for a general effect of ageing of liferafts. These concerns were reflected in an earlier amendment to resolution A.761(18) where annual liability test was introduced for liferafts older than 10 years. The annual liability tests, floor seam test and NAP test cannot be accommodated under the extended service interval concept. LSA Code amendments 5 Annex 2 contains proposed essential requirements for inflatable liferafts to be approved for extended service intervals. The following proposed amendments might need some explanatory comments: Protective arrangements To prevent undue deterioration of the liferaft, its fitting and equipment, it is important to obtain and maintain a controlled environment in and around the liferaft. Examining the acceptances given by the Administration so far under the present novel arrangement concept, it has been noted that these arrangements are all provided with a sealed protective barrier Replacement of expired items An extended service interval may make it necessary to include provisions for replacing outdated items if the extended service interval conflicts with the lifetime limits Registration of important conditions at the on-board inspections It is of vital importance to be able to verify the continued efficiency of the protective arrangements in conjunction with the intermediate on board inspection. Likewise it is important to be able to reveal an emerged inflation gas leakage. Amendments to resolution A.689(17) 6 Annex 3 contains the proposed new test standard for inclusion in resolution A.689(17). Explanatory comments to the individual proposed tests are given in the following text:.1 The liferafts shall be subjected to all the relevant tests described in resolution MSC.81(70) and to the following tests in the sequence of appearance. A representative selection of liferaft types and sizes should be subjected to the following tests using the selection criteria given in annex 3, paragraphs and ;

3 - 3 - FP 50/16.2 A number of four liferafts from each test range, as indicated in table 1 of annex 3, should be subjected to the vibration and shock test in order to accommodate the full range of subsequential tests;.3 The humidity behind the protective barrier of the liferafts in the operationally packed conditions should be measured and recorded. The humidity should not exceed [55]% rh. The proposed acceptable humidity level at less than 55% rh is considered to be a level which will not have damaging effects on the liferafts and at the same time a humidity level which will ensure proper curing of adhesive repairs which may have been performed at a scheduled service;.4 The liferaft in the operationally packed conditions should be subject to a vibration and shock test to an extend representative to actual conditions on seagoing ships. The vibration test is generally meant to verify the protective effectiveness of liferaft arrangement when subjected to the vibrations and impacts onboard a vessel during an extended period. Data for the vibration and shock impacts will be collected for a number of vessels. These data will form basis for the vibration impacts to be specified and applied in the vibration test. It is anticipated that a test procedure can be based on the significant impacts leaving out the minor vibrations and shocks in order to accommodate an accelerated test procedure. A test procedure could be set up as outlined below: Vibration and shock test for liferafts intended for extended service intervals.1 Scope To ensure the effectiveness of liferaft arrangement s capabilities of preventing moisture in getting in contact with the liferaft and its fittings, the efficiency of the protective barrier of the liferaft should be tested to the following conditions;.2 Normative reference;.3 Definitions;.4 Requirements;.5 Acceptability Acceptability is expected to focus on the intact effect of a protective barrier around the liferaft itself. Humidity behind the protective barrier can be used as criteria;.6 Testing machinery Requirements to the testing machine are basically to require that the impacts specified under test procedures can be obtained for the liferaft;.7 Mounting of the liferaft The liferaft in its operationally packed conditions in its container is to be tested. Mounting on the test machine must simulate the mounting onboard the vessel properly. Consequently, mounting instructions and requirements must be defined;

4 FP 50/ Test procedures Vibration test requirements will be set out. Collected vibration data will form the base for specifying required levels of shock and vibration. It may show suitable to introduce different procedures for different type of vessels. Parameters to be defined are expected to be among the following:.1 amplitudes for the vibration impact;.2 frequency ranges;.3 duration of the tests;.4 number of incidents ; and.5 directions of vibration;.9 Certification of testing A liferaft that has met the requirements of this test procedure should be accompanied with a certificate; and.10 Test report The results form of the test should be documented in a report..5 Items with expiry date It should be demonstrated that dated items can be replaced at on-board inspections, without destructing the efficiency of the protective barrier, if the item(s) expires before the next scheduled service;.6 Following the vibration test the liferaft, still in the operationally packed condition, should be exposed to a water spray test imposing a relative humidity to the liferaft arrangement of 100% for a period of time. The test procedure is still under development based on experimental tests with the objective of establishing an appropriate test time frame, necessary to reveal possible insufficiencies in the protective barrier. After the completion of the test the humidity behind the protective barrier should not exceed the recorded starting value by more than 2%. If the registered humidity is within the required limit the protective barrier can be considered as being intact and capable of protecting the liferafts;.7 Access to lifting hook (applicable to davit-launched liferafts only) It should be established by a test that there is an easy access to the lifting hook or bridle on davit launched liferafts after the vibration test has been carried out;

5 - 5 - FP 50/16.8 Drop test If the test subjects have proven compliance with the acceptance criteria in paragraphs and they should subsequently be subjected to the drop test described in paragraph 5.1 of resolution MSC.81(70). Even if this test is already included in the general prototype test it is considered to be essential to repeat it at this stage, because the liferafts may have become re-positioned in the container during the vibration test and subsequently the liferafts ability to inflate in an upright position may have been disabled;.9 Cold inflation test A liferaft should be subjected to a cold inflation test in accordance with paragraph following the vibration test. This test is considered to be essential to verify the liferaft's capability of inflating properly after the vibration test, which may have caused the liferaft to re-position inside the container. The cold inflation test is considered to be the most significant test when it comes to the demonstration of a proper inflation;.10 Leak test The liferafts should be subjected to the test described in Part 2, paragraphs and in order to reveal any leaks caused by previous tests; and.11 Detailed inspection The liferafts which have been tested in accordance with paragraphs to and have been found to comply with the acceptance criteria should then be subjected to a thorough visual inspection in order to reveal any wearing or chafing which may have been imposed by the previous tests. Amendments to update resolution A.761(18) 7 A proposal for amending resolution A.761(18) will be submitted to FP 50 in a separate document. 8 The collection of data from seagoing vessels, which should form the basis for the vibration/shock test, is initiated and will form the foundation for a specific accelerated test proposal, which will be submitted to the relevant Sub-Committee for consideration and approval in due course. Action requested of the Sub-Committee 9 The Sub-Committee is invited to:.1 consider the proposals set out in the annexes;.2 take into account that the proposed shock/vibration test still needs to be completed and submitted for consideration at the next session of the Sub-Committee; and.3 and take action as appropriate. ***

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7 FP 50/16 ANNEX 1 AMENDMENTS TO UPDATE SOLAS CHAPTER III Regulation Replace existing 8.3 with the following text: 8.3 An Administration, which approves inflatable liferaft arrangements, may allow for extended service intervals on the following conditions: 2 Replace existing with: The liferaft arrangement shall in addition to complying with section 4.2 of the Code comply with paragraph of the Code. 3 Keep as it is: The liferaft system shall be checked on board by certified personnel according to paragraph Keep as it is: Service at intervals not exceeding five years shall be carried out in accordance with the recommendations of the Organization. * 5 Insert new paragraph 8.3.4: After the first ten years of a liferaft s life under extended service interval it shall return to the annual service intervals stated in *** * Refer to the Recommendation on conditions for the approval of servicing stations for inflatable liferafts, adopted by the Organization by resolution A.761(18).

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9 FP 50/16 ANNEX 2 AMENDMENTS TO UPDATE THE LSA CODE 1 Insert a new paragraph : Inflatable liferafts for extended service intervals In addition to complying with all relevant requirements of 4.1 and 4,2, inflatable liferaft arrangements intended for extended service intervals shall:.1 be capable of withstanding environmental influences for the extended period of time on board seagoing vessels;.2 include protective arrangements preventing the liferaft, its fitting and equipment from getting exposed to excessive humidity;.3 include provisions for the replacement of expired items in conjunction with the annual on-board inspections;.4 replaceable dated items shall be readily accessible from the interior of the liferaft when the liferaft is inflated; and.5 include provisions, which makes it possible to record the humidity level behind the protective barrier and to record any leakage of inflation gas during the annual on-board inspection. ***

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11 FP 50/16 ANNEX 3 AMENDMENTS TO UPDATE RESOLUTION A.689(17) 1 Insert a new paragraph 5.23: 5.23 Tests for inflatable liferafts intended for extended service intervals The liferafts should be subjected to all the relevant tests described in section 5 and to the following tests in the sequence of appearance Depending on the capacity and type of liferaft subjected for approval, the Administration should from the relevant range of liferafts require:.1 two liferafts from a range of 6 to 8 persons capacity;.2 two liferafts from a range of 9 to 20 persons capacity;.3 two liferafts from a range of 21 to 39 persons capacity;.4 two liferafts from a range of 40 to 51 persons capacity;.5 two liferafts from a range of 52 to 109 persons capacity;.6 two liferafts from a range of 110 to 150 persons capacity;.7 two liferafts from a range greater than 151 persons capacity; and.8 two davit launched liferafts from a range of 25 to 39 persons capacity, to be subjected to the tests in paragraphs to in accordance with the test raft distribution table described in A test sequence should always include four liferafts collected from the relevant test ranges in paragraph and the test distribution should be in accordance with table 1 1). 1) Examples: If approval is applied for liferafts in the range 6-8 persons and for the range 21-39, two liferafts from the range and two liferafts from the range should be selected for a test sequence. If approval is applied for a 10-person liferaft only, four liferafts should be selected from range , which could be four 10-person liferafts. If approval is applied for liferafts from 3 ranges, the collection of liferafts for the test sequences should be two liferafts from the first two ranges and four liferafts from the third range.

12 FP 50/16 ANNEX 3 Page 2 No. Test Test rafts Shock/vibration test X X X X Dated item replacement test X X X X Humidity test X X X X Drop test X X Cold inflation test X X Access to lifting hook test (D/L rafts only) X X Leak test X X X X Detailed inspection X X X X Additional tests.1 Recording of humidity Table 1 Test raft distribution The humidity behind the protective barrier of the four liferafts in the test sequence and in the operationally packed conditions should be measured and recorded. The humidity should not exceed [55]% rh;.2 Vibration/shock test The liferafts in the operationally packed conditions should be subjected to vibration and shock tests. (A proposal for a detailed test procedure based on collected data from seagoing vessels will be submitted to the Sub-Committee);.3 Replacement of items with expiry time It should be demonstrated that dated items can be replaced without destructing the efficiency of the protective barrier. This test should be carried out after the vibration test and compliance should be proven through the humidity test;.4 Humidity test Following the vibration test the liferafts, still in the operationally packed condition, should be exposed to a water spray test imposing a relative humidity to the liferaft arrangement of 100% for a period of time (exact test procedure still needs to be evaluated and finalized). After the completion of the test the humidity behind the protective barrier should not exceed the recorded starting value by more than [2]%;.5 Drop test If the test subjects have proven compliance with the acceptance criteria in paragraphs 3.4 and 3.5, two liferafts should subsequently be subjected to the drop test described in paragraph 5.1;

13 FP 50/16 ANNEX 3 Page 3.6 Cold inflation test Two liferafts should be subjected to a cold inflation test in accordance with paragraph following the humidity test;.7 Access to lifting hook (applicable to davit-launched liferafts only) It should be established by a test that there is easy access to the lifting hook or bridle on davit launched liferafts after the vibration test has been carried out;.8 Leak test The liferafts should be subjected to the test described in part 2, paragraphs and in order to reveal any leaks caused by previous tests; and.9 Detailed inspection The liferafts, which have been subjected to the above specified tests and have been found to comply with the acceptance criteria, should then be subjected to a thorough visual inspection in order to reveal any damage, wearing or chafing which may have been imposed by the previous tests.