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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.

INTERNATIONAL MARITIME ORGANIZATION

IMO

E

MARITIME SAFETY COMMITTEE 74th session Agenda item 5

MSC 74/5/5 26 February 2001 Original: ENGLISH

BULK CARRIER SAFETY

Formal Safety Assessment of Life Saving Appliances for

Bulk Carriers FSA/LSA/BC

Submitted by Norway and ICFTU

SUMMARY

Executive summary:

This document is submitted in response to the MSC 70 decision to include Life Saving Appliances (LSA) as part of the ongoing activity with carrying out Formal Safety Assessment studies for Bulk Carriers. The current document includes the full FSA report, including the recommendations for decision making. The recommendations from the FSA are summed up in the executive summary of the FSA report. The Norwegian project has previously reported on the decision parameters and acceptance criteria to be applied in the study. This preparatory step to FSA was reported in MSC 72/16. The hazard identification (FSA Step 1) was reported in MSC 73/INF.7.

Action to be taken:

The Committee is invited to note the recommendations given in Chapter 7 of the attached FSA report and decide as appropriate.

Related documents:

MSC/Circs.829 and 765; MSC 70/4/2, paragraphs 16 to 18; MSC 70/4/Add.1; MSC 70/INF.14; MSC 70/23, paragraph 4.28; MSC 71/23, paragraph 4.4; MSC 72/16; MSC 73/INF.7; DE 44/9/1; and DE 44/INF.7.

1 At MSC 70 the Committee considered proposals (MSC 70/4/2, paragraphs 16 to 18), that new bulk carriers should be required to carry a safe haven which would float free if the ship were to sink, and that existing bulk carriers should be required to be retrofitted with free-fall lifeboats. Some delegations were opposed to the application of the latter, and the Committee invited interested delegations to submit relevant proposals, taking also into account, as appropriate the Interim Guidelines for Systematic Application of the Grandfather Clauses (MSC/Circ.765). In this context, the Committee also agreed that the issue of Life Saving Appliances (LSA) for bulk carriers should also be included in the FSA study, in accordance with MSC/Circ.829, to be undertaken as proposed by the United Kingdom (MSC 70/4/Add.1 and MSC 70/INF.14).

MSC 74/5/5 - 2 -

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2 An FSA project on LSA for bulk carriers has now been carried out in Norway. The project was carried out by Det Norske Veritas in co-operation with participants from Norwegian Maritime Directorate, Norwegian Union of Marine Engineers, Umoe Schat-Harding, Norwegian Shipowners Association and International Transport Workers Federation. The project included active involvement of the participants; in particular in the hazard identification (Step 1 of FSA), the identification of Risk Control Options (Step 3 of FSA) and in reviewing the project results. 3 Agreeing on the decision parameters and risk acceptance criteria is generally a preparatory step to any FSA. As this topic is not explicitly dealt with in the current version of the FSA Guidelines (MSC/Circ.829), the project first prepared a submission on this important issue (MSC 72/16). The criteria proposed in this document have been adhered to in this FSA. 4 The hazard identification was carried out for conventional lifeboats, throw overboard liferafts, davit/crane launched liferafts and free-fall lifeboats. The hazards were ranked according to the proposal in MSC 72/16. However, the scale used was per evacuation rather than per year (annual). The result of the hazard identification was reported in MSC 73/INF.7, and is available as annex 1 to the attached FSA report. 5 The full FSA report is attached, following the standard reporting format for FSA studies (MSC/Circ.829, annex 2). All other background material is made available as annexes to the FSA report. All these annexes are made publicly available on the web as given in the list of annexes at the end of the report. Alternatively, those interested may also receive the annexes by contacting [email protected].

***

MSC 74/5/5

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ANNEX

1 FORMAL SAFETY ASSESSMENT OF LIFE SAVING APPLIANCES FOR BULK CARRIERS (FSA/LSA/BC)

2 SUMMARY 2.1 This FSA study relates to life saving appliances of bulk carriers1. The study is considered representative for all SOLAS bulk carriers2 with the exception of bulk carriers less than 85 meters with equivalent life saving arrangements (rescue boat and liferafts). The study has been carried out for the four types of survival craft in use: Conventional (open or enclosed) lifeboats, free-fall lifeboat, davit-launched liferafts and throw over board liferafts. The risk reduction effects of introducing free-fall lifeboats as a mandatory requirement is quantified, whilst conventional lifeboats are considered the base case in Step 2 of FSA. The Risk Control Options (RCOs) that has been consider relates to:

- Sheltered mustering and lifeboat area

- Remote control of the ship from the mustering area

- Level alarms to monitor water ingress in all holds and forepeak

- Individual immersion suits to all personnel

- Free-fall lifeboat

- Free-fall lifeboat with an additional free float mode

- Marine evacuation systems for throw overboard liferafts

- Enclosing open lifeboats for all existing ships with open lifeboats

- Redundant trained personnel

- Improved pick-up function (crane)

After carrying out an extensive review of historic data and completing all steps of the FSA it was concluded that the following RCOs are providing considerable improved lifesaving capability in a cost-effective manner:

- Free-fall lifeboats with an additional free float mode. This solution is slightly better that the Free-fall lifeboat solution itself, which is also considered cost effective.

- Water level alarm with continuous water level indication in all holds and fore peak (New and Existing Ships).

- Personal immersion suits to all personnel (New and Existing Ships).

1 The DNV reference is: Skjong, R. and Wentworth, B.H Formal Safety Assessment of Life Saving Appliances for Bulk Carriers DNV Report 2000-0539. 2 Ships above 500 gross tonnage

MSC 74/5/5 ANNEX Page 2

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The free-fall lifeboat is strongly recommended for new ships. It is noted that the success rate in evacuation from existing ships remains rather low also after implementing the suggested RCOs. This may call for additional measures, in particular focused on crew competence and training for these ships. The analysis is generic, and further RCOs may also be required if sub-groups of bulk carriers turn out to be associated with higher risks. 2.2 The Committee is invited to review the recommendations. This should be done together with the review of other recommendations from other ongoing FSA activities. The recommendations are based on data from the period 1991-1998. If other RCOs are implemented that reduces the need for evacuation, this will change the cost effectiveness of life saving appliances proportionally. The report reproduces the estimation in detail, for each accident scenario. It is therefore possible to update the results in this submission by hand-calculation, based on assumptions of risk reduction by implementing other RCOs recommended by other ongoing FSA project activities. 2.3 Related documents: MSC/Circs.829&765, MSC 70/4/2 paragraphs 16 to 18, MSC 70/4/Add.1, MSC 70/INF.14, MSC 70/23 paragraph 4.28, MSC 71/23, paragraph 4.4, MSC 72/16, MSC 73/INF.7, DE 44/9/1 and DE 44/INF.7. 3 DEFINITION OF THE PROBLEM 3.1 The problem addressed relates to the identification of the most cost effective Life Saving Appliances that could bring the fatality rates in the bulk carrier accidents to As Low As Reasonably Practicable. It has previously been established, see e.g. MSC 72/16 that bulk carrier fatality statistics is high in the ALARP area, and any RCO that is cost effective should be implemented. In considering cost effectiveness it is necessary to look into the accident scenarios where evacuation is necessary and where the ships Life Saving Appliances have to be used. The probability of the various accident scenarios (Collision, Contact, Fire, Explosion, Foundering, Hull Failure, Machinery Failure, and Wrecked/Stranded) is fairly well established in accident statistics. The exact method of evacuation used in each accident scenario is less well established. The current report, therefore contains an analysis of the available information, and establishes the success rate in present situation. 3.2 The following regulations are affected by the recommendations:

- SOLAS 1974 as amended 1996, chapter III, regulation 31, 1.1 and 1.2 relating to survival craft.

- SOLAS 1974 as amended 1996, chapter III, regulation 32, 3.2 relating to immersion suits.

- SOLAS 1974 as amended 1997, chapter XII, regulation 11, relating to water level alarm with continuous water level indication (The requirement is a modification of IACS UR S24 requiring water level alarms no later than the first intermediate or the first special survey, to be held after 1 January 1999 whichever comes first. UR S24 does not require continuous water level indication).

3.3 The generic risk model is established in detail in ANNEX II of the report. The model is built around generic event trees. The event trees are identical for all accident scenarios, but the probabilities are different conditional on the initiating event defining each accident scenario. In

MSC 74/5/5 ANNEX

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order to be able to apply the model in cases where a Risk Control Option is implemented, the model has to be very detailed. The event trees are therefore detailed, and the branch probabilities are assessed conditional of each initiating event. Some of the branch probabilities are broken down further and fault trees are used. All available data of real evacuations of bulk carriers in the period 1991-1998 have been applied. The analysis is based on LMIS (Lloyd's Maritime Information Services) incident data, with supplementary information from LCRs (Lloyd's Casualty Reports). None of the fields in the LMIS database identify whether or not an evacuation has taken place and, to our knowledge, no other comprehensive list of evacuation is available. Therefore, cases in which evacuation has or should have taken place is identified as follows:

- Any incidents where the LMIS complementary text mentions "crew rescued/abandoned ship".

- Incidents where the LMIS complementary text mentions "crew missing/dead" and evacuation confirmed by LCR.

- Incidents where the LMIS severity is categorised as total loss3 and evacuation confirmed by LCR.

- Incidents where the LMIS basic retrieval group is foundered4 and evacuation is confirmed by LCR.

- All total loss and foundering events in which it seems that the entire crew is either reported as killed or missing.

To be able to establish the detail model, various other sources of information has been used, including generic human reliability data from handbooks. Many times, data have been produced based on judgement. Whichever method has been used, the assumptions has been documented in ANNEX II. It should also be noted that the model reproduces the actual historic data, and changes of assumptions will very often contradict the factual information. The model is therefore in this respect a best judgement consistent with available information. An additional advantage of this approach is therefore that a consistent decision model may be used, that are transparent and documented. 4 BACKGROUND INFORMATION 4.1 The development of the requirements for life saving appliances are described in ANNEX I. In brief, the main developments refers to the years 1986 and 1998: Bulk carriers with keel laid prior to 1 July 1986:

- The lifeboats are normally open. - Only off-load hook was required for the release mechanism of the launching appliances

for the lifeboats.

3 Total loss refers to a ship, which has ceased to exist, either by virtue of the fact that the ship was irrecoverable or was broken up as a consequence of that casualty. 4 Foundered includes ships which sank as a result of heavy weather, springing leak, breaking in two, etc.


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- Three immersion suits are required for each open lifeboat. Thermal protection aids are required for the remaining crew.

Bulk carriers with keel laid on or after 1 July 1986:

- Totally enclosed lifeboats are required.

- Two release capabilities; off-load and on-load are required for the release mechanism of the launching appliances for the lifeboats (except in single fall).

Bulk carriers with keel laid after 1 July 1998, SOLAS 1996 Amendments:

- Two release capabilities; automatic release when waterborne and on-load are required for the release mechanism of the launching appliances for the davit-launched liferafts.

With reference to the above, free-fall lifeboats are optional, and therefore a Risk Control Option (RCO) to be considered in step 3 of the Formal Safety Assessment (FSA). Still free-fall lifeboats are being installed on an increasing number of bulk carriers. A complete review of the life saving appliances installed on DNV classed bulk carriers showed that about 15% of new bulk carriers are equipped with a free-fall lifeboat. It is not known if this is representative for all bulk carriers. This FSA indicates that the decision to install free-fall lifeboats is a rational decision by the ship owner. Bulk carriers with keel laid on or after 1 July 1986 are also required to be equipped with a rescue boat. Immersion suites are required for the personnel designated to the operation of the rescue boat. This implies that bulk carriers are normally equipped with at least three immersion suits. 4.2 Detailed casualty statistics for evacuation may be found in ANNEX II. The summary from ANNEX II is reproduced in Table 1. The table relates to evacuations where the method of evacuation is known.

Table 1 Effect of Evacuation Method in Bulk Carrier Evacuations, 1991-98

EVACUATION METHOD NO. OF EVENTS

FATA- LITIES

NUMBER TO BE

EVACUATED

PROB. OF FATALITY

TRANSFERRED TO HELICOPTER 8 17 219 0.078 TRANSFERRED TO VESSEL 8 1 201 0.005 LIFEBOAT ONLY 4 57 112 0.509 Lifeboat Then picked up by helicopter 0 Lifeboat Then picked up by vessel 3 24 79 0.304 Lifeboat - Unknown whether picked up by helicopter or vessel 1 33 33 1.000 LIFERAFT ONLY 3 10 68 0.147 Liferaft Then picked up by helicopter 0 - - - Liferaft Then picked up by vessel 3 10 68 0.147 UTILISING BOTH LIFEBOAT AND LIFERAFT 13 81 310 0.261 Lifeboat and liferaft - Then picked up by helicopter 1 21 25 0.840 Lifeboat and liferaft - Then picked up by vessel 9 4 209 0.019 Lifeboat and liferaft - Then picked up by helicopter and vessel 1 5 25 0.200 Lifeboat and liferaft - Unknown whether picked up by helicopter or vessel

2 51 51 1.000

MSC 74/5/5 ANNEX

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Table 1 Effect of Evacuation Method in Bulk Carrier Evacuations, 1991-98 (contd)

EVACUATION METHOD NO. OF EVENTS

FATA- LITIES

NUMBER TO BE

EVACUATED

PROB. OF FATALITY

DIRECT TO SEA 6 99 127 0.780 Direct to sea - Then picked up by helicopter 0 - - - Direct to sea - Then picked up by vessel 4 63 90 0.700 Direct to sea - Unknown whether picked up by helicopter or vessel 2 36 37 0.973 TRANSFERRED TO HELICOPTER and EVACUATION BY SURVIVAL CRAFT

3 1 78 0.013

TRANSFERRED TO HELICOPTER and JUMPING/Then picked up by vessel

1 0 25 0.000

TOTAL 46 266 1140 0.233

A total of 117 evacuations of bulk carriers were identified during 1991-98. The ship population exposure during this time is estimated as 44,732 ship years (Lloyd's Register's World Fleet Statistics). This gives a total evacuation frequency of 2.6.10-3 per ship year. For comparison, the frequency of evacuation from merchant ships in general has previously been estimated as exactly the same, 2.610-3, per ship year (COMSAR 3/2). Distributed with respect to type of accidental event where this could be identified, the resulting evacuation frequencies are listed in Table 2, and described in further detail in ANNEX II. The number of crewmembers onboard is obtained by multiplying the number of events with the average crew size, i.e. 23.7, based on events for which crew size is identified. As seen from Table 2, the accidental event of foundering is clearly the event that most often is the cause of evacuation. In ANNEX II, it is also explained that these evacuations take place in severe weather.

Table 2 Evacuation frequencies for different types of events 1991-98

Type of Event No. of Events5

Evacuation Frequency

[per ship year]

Fatalities No. on board

Probability of fatality [%]

Collision 14 3.110-4 116 332 35 Contact 5 1.110-4 54 119 45 Fire/Explosion 16 3.610-4 6 379 2 Foundered 51 1.110-3 618 1209 51 Hull failure 5 1.110-4 0 119 0 Machinery failure 1 2.210-5 0 24 0 Wrecked/Stranded 23 5.110-4 0 545 0 Total 115 2.610-3 794 2727 29

4.3 A large number of sources of information has been used in the study, e.g. other reports, handbooks, expert judgement. These sources of information are referenced in the report and annexes. Where uncertainty in data make a recommendation unclear, this is recorded in the final recommendations.

5 Two events excluded because of lack of relevance


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5 METHOD OF WORK 5.1 The main work in the project has been carried out by risk assessment experts, listed as recorder and facilitator of the hazard identification in ANNEX I. The work with the cost effectiveness assessment and the risk assessment was done independently and in sequence. This approach has the advantage that the risk models were reviewed in detail when the cost effectiveness assessment was carried out (repetitive use of the models). The risk model is classical, based on event trees supported by some fault trees. One risk analyst then developed the models, and the result was reviewed by two other experts, the models were subsequently updated, and thereafter reviewed by all participants in the project. The cost estimation has been done primarily by contacting suppliers of life saving appliances, training centers, yards and ship owners. This is necessary to be able to estimate all relevant costs for equipment, installation, maintenance, replacement, training etc. Much of the basis of the cost estimates has been received by promising that the information should not be reproduced in detail, and without listing actual names of suppliers. This did not cause any problem as independent estimates received were close, and deviations were possible to explain (e.g. factual variability in cost in West-Europe and Far-East). This report reproduces high and low estimates. This reflects the variation in costs between suppliers and variation due to the fact that the technical solutions are not specified in detail. It may be noted that this is the case also for technical solutions that are certified according to current regulations. 5.2 There has been two major meeting during the project: The HAZID Meeting, See ANNEX I, and a brainstorming meeting for identifying/agreeing on which risk control options should be analyzed. The participants in the HAZID meeting are listed in ANNEX I and the participants in the RCO meeting are listed in ANNEX VI. All reports has been circulated for comments by the project participants: Norwegian Maritime Directorate, Norwegian Shipowners Association, UMOE-Schat Harding, International Transport Workers Federation, Norwegian Union of Marine Engineers and Det Norske Veritas. Final review meetings were arranged on 15-16 February 2001, see ANNEX VIII. 5.3 The project started in January 2000 and was finished in February 2001. 6 DESCRIPTION OF THE RESULTS ACHIEVED IN EACH STEP STEP 1 - HAZARD IDENTIFICATION 1. The hazard identification was carried out by use of the Structured What If Technique

(SWIFT). This technique is suited for hazard identification in meetings with a multidisciplinary team of relevant experts. The technique require active participation by experienced personnel, and is carried out as a brainstorming (diverging and converging phase), followed by a ranking of the identified hazards.

MSC 74/5/5 ANNEX

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The hazard were identified and ranked separately for conventional lifeboats, free-fall lifeboats, davit launched liferafts, and throw overboard liferafts. The hazard identification was carried out from the occurrence of the initiating event, through mustering, abandoning, survival at sea, and the final rescue.

2. The hazard identification is expected to be representative for the scope of the FSA. No

other limitation was imposed. On the contrary, the hazard identification is expected to be representative for other ship types with similar life saving appliances and similar accident scenarios. The frequency of the various accident scenarios for bulk carriers is listed in Table 2, and may be very different for other ship types. If an attempt is made to use the result in this report for other ship types, this difference should be accounted for. In the hazard ranking this variation in probabilities of the initiating events was not considered, as these frequencies are known from accident statistics.

3. The results are presented in detail in ANNEX I. The existence of these results were

announced and summarized in MCS 73/INF.7 pointing to a web-site where this part of the FSA has been publicly available since 2000-09-05. Hazards 1-11 are generic for all survival crafts. Hazards 12-18 are different for the different categories of survival crafts. Hazards 19-20 relates to survival at sea and rescue and are only separated into rafts and boats, respectively. Whilst the description is the same, the ranking was carried out for each type of survival craft.

All hazards were ranked individually by each member of the team (excluding the facilitator and recorder). An average risk index was estimated for each hazard.

The resulting ranking was (highest risk first): Conventional lifeboat pre 1986, conventional lifeboat post 1986, throw over board liferafts, davit/crane launched liferafts, free-fall lifeboats. The result was the same based on the sum of the risk indices and based on the highest risk index. Details, of individual risk ranking were transferred to the hazard log-sheets and may be found in ANNEX I.

The recommendations from the HAZID are considered as recommendation for further assessment and not as recommendations for decision-making.

STEP 2 - RISK ASSESSMENT The individual and societal risk for Bulk Carriers has been presented previously in MSC 72/16. The assumption made in building the risk model is, in agreement with MSC 72/16, that risks are in the As Low As Reasonably Practicable (ALARP) area but not ALARP. This implies that all RCOs that may reduce the risk to ALARP should be implemented. The risk model developed is therefore suited for cost effectiveness assessment of the RCOs identified. Potential Loss of Life (PLL) is the only decision parameter predicted by the model, as the LSA does not have any important impact on environmental or economic risk. EVACUATION MODEL In order to model the evacuation process, the following preference of the crew is assumed:


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1. Gangway to shore

2. Direct transfer to other vessel

3. Helicopter

4. Lifeboat

5. Liferaft

6. Direct to sea

In general, the most preferred option will be used assuming that it is available, has sufficient capacity and can be used in the time available. Regarding gangway to shore, this is not considered relevant in bulk carrier evacuation. The evacuation model is illustrated by a number of generic event trees, which are independent of type of accident scenario, e.g. foundering, fire/explosion, etc. The event trees develop in time sequence from left to right. For each header there are two branches. The branch with yes outcome points up, the branch with a no outcome points down, when the header is formulated as a question. The probability values associated with the different branches in the event trees are varying dependent on the accident type. The detailed sources of the probabilities are described in ANNEX II. The description in this main report is a summary, and a reader interested in the full assessment should read ANNEX II and not the summary. The sequence of events following an initiating event until selection of evacuation method is discussed in ANNEX II.3.2 and illustrated by the event tree in Figure 1. The process of selecting evacuation method and abandoning is discussed in ANNEX II.3.3 and illustrated by the event tree in Figure 2. Lifeboat evacuation is discussed in further detail in ANNEX II.3.3.1 and illustrated by the event tree in Figure 3, while davit/crane launched liferaft and throw overboard liferaft evacuations, respectively, are discussed in ANNEX II.3.3.2 and ANNEX II.3.3.3 and illustrated by event trees in Figure 4 and Figure 5. The resulting probabilities of fatality, associated with the different types of accidental events, are presented and discussed in ANNEX II.3.4. To illustrate typical sequences of events associated with evacuation, the sequences of events associated with evacuation utilising conventional lifeboat, davit/crane launched liferaft and throw overboard liferaft are listed in Table 3.

Table 3 Sequences of Events

Conventional lifeboat Liferafts Throw over board

Liferafts Davit/Crane Launched

1. Initiating event 2. Evaluation of situation 3. Decision to muster 4. Mustering alarm 5. Escape to mustering station 6. Mustering 7. Search for missing persons 8. Selection of life saving appliances

Same

Same

MSC 74/5/5 ANNEX

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Table 3 Sequences of Events (contd)

Conventional lifeboat Liferafts Throw over board

Liferafts Davit/Crane Launched

9. Preparation of equipment 10. Decision to abandon ship 11. Boarding 12. Lowering 13. Release 14. Clear ship 15. Survival at sea 16. Rescue

9. Preparation of equipment 10. Decision to abandon ship 11. Launching 12. Boarding 13. Clear ship 14. Survival at sea 15. Rescue

9. Preparation of equipment 10. Decision to abandon ship 11. Boarding 12. Launching 13. Release 14. Clear ship 15. Survival at sea 16. Rescue

The model is developed by following an individual crewmember. In some nodes of the event tree the probability of a situation is modelled, while in some nodes the fatality probability is modelled, as indicated by the relevant header in the event tree. MUSTERING In the following section, the following events are discussed, i.e. the events following an initiating event until preparation of the LSA:

1. Initiating event

2. Evaluation of situation

3. Decision to muster

4. Mustering alarm

5. Escape to mustering station

6. Mustering

7. Search for missing persons

8. Selection of life saving appliances

The modelling of the sequence is illustrated by the event tree in Figure 1. (Note that one "sub-tree" is repeated four times. That is, the scenario of jumping to sea, awaiting and being rescued may occur in the case that there is a faulty evaluation of the situation, untimely decision to muster, unable to reach mustering station and not terminating search for missing personnel in time.) The values associated with the different branches of the event tree differ with respect to type of initiating event, as discussed in ANNEX II. The values are summarised in Table 4. For further details on the basis for the probabilities and sub-models see ANNEX II, section 3.2.


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Table 4 Branch Probabilities for Mustering

Branch probabilities

Col

lisio

n

Con

tact

Fire

/ Ex

plos

ion

Foun

dere

d

Hul

l/ M

achi

nery

Wre

cked

/ St

rand

ed

Fatality as result of initiating event 0.0001 - 0.007 - - - Faulty evaluation of situation 0.31 0.31 - 0.37 - - Fatality as a result of not jumping to sea - given faulty evaluation of situation

1 1 - 1 - -

Untimely decision to muster 0.03 0.03 0.015 0.03 0.03 0.03 Fatality as a result of not jumping to sea - given untimely decision to muster

0.90 0.90 0.90 0.95 0.95 0.95

Unable to reach mustering station 0.06 0.06 0.03 0.07 0.02 0.06 Fatality as a result of not jumping to sea - given unable to reach mustering station

0.95 0.95 0.95 1 0.95 0.95

Not terminating search in time 0.04 0.04 0.04 0.04 0.04 0.04 Fatality as a result of not jumping to sea - given not terminating search in time

0.625 0.625 0.625 0.625 0.625 0.625

Fatality associated with jumping and awaiting rescue 0.358 0.323 0.420 0.970 0.420 0.323 Fatality as a result of not successfully rescued from the sea 0.016 0.016 0.021 0.050 0.021 0.016


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Initiating event Fatality as result Faulty evaluation Untimely decision Unable to reach Not terminating search Fatality as a result Fatality associated Fatality as a result of not requiring evacuation of initiating event of situation to muster mustering station in time of not jumping to sea With jumping to sea successfully rescued

Event Tree - Abandoning

Figure 1 Event Tree - Mustering


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ABANDONING Following search for onboard missing persons, a decision has to be made with respect to selecting and possibly preparing the LSAs. Based on the list of preferred types of evacuation options, direct transfer to another vessel is the most preferred option. The model for the various LSAs is illustrated by the event tree in Figure 2, while the associated factors are discussed in ANNEX II Section III.3 and summarised in Table 5.

Table 5 Probability Values for Abandoning

Probability value

Col

lisio

n

Con

tact

Fire

/ Ex

plos

ion

Foun

dere

d

Hul

l/Mac

hine

ry

Wre

cked

/ St

rand

ed

Other vessel available 0.17 0.17 0.17 0.17 0.17 0.17 Fatality in evacuation - given vessel evacuation

0.02 0.02 0.02 0.02 0.02 0.02

Helicopter available 0.11 0.11 0.11 0.02 0.11 0.11 Fatality in evacuation - given helicopter evacuation

0.04 0.04 0.04 0.04 0.04 0.04

Lifeboat available 0.845 0.925 0.525 0.925 0.925 0.875 Rescue boat sufficient and available 0.02 0.03 0.03 0.03 0.06 0.03 Fatality in evacuation -given rescue boat

0.06 0.06 0.06 0.06 0.06 0.06

Liferaft available - Davit/Crane launched 0.39 0.44 0.19 0.44 0.44 0.44 Liferaft available - Throw overboard 0.44 0.49 0.24 0.49 0.49 0.49 Fatality as a result of not jumping to sea 0.25 0.25 0.25 0.25 0.25 0.25


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Terminating search Other vessel Helicopter Lifeboat Rescue boat Liferaft Fatality in Fatality as a result Fatality associated Fatality as a result of not

and rescue in time Available available available sufficient available evacuation of not jumping to sea with jumping to sea successfully rescued

and available

Event Tree - Lifeboat

Event Tree - Liferaft

Figure 2 Event Tree - Abandoning


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Lifeboat Unsuccessful Untimely Fatality due to Unsuccessful Unsuccessfully Fatality as a Fatality Fatality Fatality as a result available Preparation of decision unsuccessful Lowering clearing ship result of not associated associated with of not successfully Equipment to abandon boarding jumping to sea with jumping to sea being at sea rescued

Figure 3 Event Tree - Lifeboat Evacuation


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LIFEBOAT Evacuation by lifeboat is discussed further in ANNEX II, as well as illustrated in the event tree in Figure 3. The sequence of events following the decision to utilise conventional lifeboats is:

9. Preparation of equipment

10. Decision to abandon ship

11. Boarding

12. Lowering

13. Release

14. Clear ship

15. Survival at sea

16. Rescue

The different factors shown in the event tree is discussed ANNEX II, Section 3.3.1, and the probability values are summarised in Table 6.

Table 6 Probability Values for Lifeboat Evacuation

Probability value

Col

lisio

n

Con

tact

Fire

/ Ex

plos

ion

Foun

dere

d

Hul

l/Mac

hine

ry

Wre

cked

/ St

rand

ed

Unsuccessful preparation of equipment 0.013 0.013 0.013 0.013 0.013 0.013 Fatality as a result of not jumping to sea - given unsuccessful preparation of equipment

0.25 0.25 0.25 0.25 0.25 0.25

Untimely decision to abandon 0.04 0.04 0.04 0.04 0.04 0.04 Fatality as a result of not jumping to sea - given untimely decision to abandon

0.25 0.25 0.25 0.25 0.25 0.25

Fatality due to unsuccessful boarding 0.01 0.01 0.01 0.05 0.01 0.01 Unsuccessful lowering 0.043 0.043 0.043 0.046 0.043 0.043 Fatality as a result of not jumping to sea - given unsuccessful lowering

0.5 0.5 0.5 0.5 0.5 0.5

Unsuccessfully clearing ship 0.0225 0.0225 0.0225 0.0225 0.0225 0.0225 Fatality as a result of not jumping to sea - given unsuccessfully clearing ship

0.5 0.5 0.5 0.5 0.5 0.5

Fatality associated with being at sea 0.05 0.05 0.05 0.05 0.05 0.05 Fatality as a result of not successfully rescued 0.0005 0.0005 0.0005 0.03 0.0005 0.0005

DAVIT/CRANE LAUNCHED LIFERAFTS For davit/crane launched liferafts, the sequence of events following the decision to utilise liferafts is as follows:


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11. Boarding

12. Launching

13. Release

14. Clear ship

15. Survival at sea

16. Rescue

The model for davit/crane launched liferaft is illustrated by the event tree in Figure 4, discussed in ANNEX II, Section 3.3.2, and summarised in Table 7.

Table 7 Probability Values for Davit/Crane Launched Liferaft Evacuation Probability value

Col

lisio

n

Con

tact

Fire

/ Ex

plos

ion

Foun

dere

d

Hul

l/Mac

hine

ry

Wre

cked

/ St

rand

ed


0.25 0.25 0.25 0.25 0.25 0.25


0.25 0.25 0.25 0.25 0.25 0.25

Fatality due to unsuccessful boarding 0.01 0.01 0.01 0.05 0.01 0.01 Unsuccessful lowering 0.043 0.043 0.043 0.043 0.043 0.043 Fatality as a result of not jumping to sea - given unsuccessful lowering

0.75 0.75 0.75 0.75 0.75 0.75


0.75 0.75 0.75 0.75 0.75 0.75



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Liferaft Unsuccessful Untimely Fatality due to Unsuccessful Unsuccessfully Fatality as a Fatality Fatality Fatality as a result available Preparation of Decision unsuccessful lowering Clearing ship result of not associated associated with of not successfully Equipment To abandon boarding jumping to sea with jumping being at sea rescued

Figure 4 Event Tree - Davit/Crane Launched Liferaft Evacuation


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Liferaft Unsuccessful Untimely Unsuccessful Fatality due Unsuccessful Unsuccessfully Fatality as a Fatality Fatality Fatality as a result available Preparation of decision launching to jumping Boarding clearing ship result of not associated associated with of not successfully Equipment to abandon to board jumping to sea with jumping being at sea rescued

Figure 5 Event Tree - Throw Overboard Liferaft Evacuation


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THROW OVERBOARD LIFERAFT For throw overboard liferafts, the sequence of events following the decision to utilise the liferaft is as follows:



11. Launching

12. Boarding

13. Clear ship

14. Survival at sea

15. Rescue

The model for throw overboard liferaft is illustrated by the event tree in Figure 5, discussed in ANNEX II, Section 3.3.3 and summarised in Table 8.

Table 8 Probability Values for Throw Overboard Liferaft Evacuation

Probability value

Col

lisio

n

Con

tact

Fire

/ Ex

plos

ion

Foun

dere

d

Hul

l/Mac

hine

ry

Wre

cked

/ St

rand

ed


0.25 0.25 0.25 0.25 0.25 0.25


0.25 0.25 0.25 0.25 0.25 0.25

Unsuccessful launching 0.03 0.03 0.03 0.03 0.03 0.03 Fatality as a result of not jumping to sea - given unsuccessful launching

0.25 0.25 0.25 0.25 0.25 0.25

Fatality due to jumping to board 0.02 0.02 0.02 0.02 0.02 0.02 Unsuccessful boarding 0.3 0.3 0.3 0.3 0.3 0.3 Fatality associated with being at sea - given unsuccessful boarding

1 1 1 1 1 1


0.75 0.75 0.75 0.75 0.75 0.75



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RESULTS The resulting probabilities of fatality and PLL (Potential Loss of Life) are summarised in Table 9 for the different types of accidental events considered. DISCUSSION The model reflects the data quite well. This is mainly due to the method used, where actual data are used as basic input and broken down to branch probabilities in the event trees. Still many of the branch probabilities had to be assessed based on comparison with other ship types and other industries, like e.g. offshore. Also some probabilities are assessed by using generic human reliability data from the literature. This is currently mainly a result of the lack of good data from shipping.

Table 9 Probabilities of Fatality Associated with Evacuation

Based on model Based on statistics Type of Event Probability of fatality [%]

PLL [per ship year]

Probability of fatality [%]

PLL [per ship year]

Collision 45.7 3.3610-3 35 2.610-3 Contact 44.1 1.1510-3 45 1.210-3 Fire/Explosion 27.7 2.310-3 2 1.710-4 Foundered 55.4 1.4410-2 51 1.310-2 Hull/Machinery failure 16.2 5.1210-4 0 0 Wrecked/Stranded 20.2 2.4510-3 0 0

The need to make a detailed model is defined by a need for a model that may be used to quantify the effect of the RCOs (Risk Control Options). The HAZID report was therefore used as input in evaluating which level of detail is necessary. Regarding fire/explosion, hull/machinery and wrecked/stranded events, the probabilities of fatality resulting from the model may be somewhat conservative. This may be due to not sufficiently accounting for the time factor in the model, i.e. in some cases the crew have more time available than in other cases. However, as the probabilities of fatality resulting from statistics are based on a fairly limited number of events, these values are associated with some uncertainty, which also may explain the differences between the results associated with the model and the statistics. In the further estimation of the risk reduction effects this model has been used, and data modified to reflect the effect of the RCO. STEP 3 - RISK CONTROL OPTIONS The RCOs were largely identified in the hazard identification meeting, and agreed in a separate RCO meeting, in a multidisciplinary team of experts. The hazard identification focused to some degree on the difficulty in the decision making process associated with the decision to muster, and one of the RCOs relates to this and are not normally part of the topics covered in SOLAS chapter III.2. The RCOs identified for further assessment were:


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- Sheltered mustering and lifeboat area (SMA)

- Remote control of the ship from the mustering area (RC)6

- Level alarms to monitor water ingress in all holds and forepeak (LA)

- Individual immersion suits to all personnel (IS)

- Free-fall lifeboat (FF)

- Free-fall lifeboat with an additional free-float mode (FFFF)

- Marine Evacuation Systems for throw overboard liferafts (MES)

- Enclosing open lifeboats for all existing ships with open lifeboats (EOL)

- Redundant trained personnel (RTP)

- Improved pick-up function (crane) (PUF)

It should be noted that in addition to these RCOs, the hazard identification identified some more general problems, that are difficult to cover in a cost effectiveness assessment both because the risk model must be very accurate, and the costs are small. With the poor overall performance of LSA designers of LSA should always look for simple and reliable solutions, that are easy and fast to understand and operate, and require as little maintenance and training as possible. Reliable automated system may be better than reliance on complicated manual operations, which may work in theory but have poor performance in crisis. The modeling of the effect of free-fall lifeboat requires the development of a new event tree, replacing the models for conventional lifeboats. This model and input is described in detail in ANNEX III. The risk reduction of all other RCOs is assessed in ANNEX IV, including the cost and cost effectiveness assessment. The result of the risk reduction is given in the change in the probability of successful evacuation for each accident scenario, in Table 10.

Table 10: Probability of fatality in current situation (%) and reduction with RCO implemented (Change in % value)

Current SMA RC LA IS FF FFFF7 MES EOL RTP PUF Collision 45.7 -0.3 -0.3 0.0 -1.2 -1.1 -2.6 -0.3 -0.7 -0.2 0.0 Contact 44.1 -0.3 -0.3 0.0 -0.9 -1.3 -3.0 -0.1 -0.7 -0.2 0.0 Fire/ Explosion

27.7 -0.3 -0.2 0.0 -4.5 +0.4 +0.4 -1.0 -0.7 -0.2 0.0

Foundering 55.4 -0.9 -0.3 -14.8 -2.0 -4.1 -4.9 -0.1 -0.6 -0.4 -0.5 Hull/ Machinery

16.2 -0.5 -0.5 0.0 -1.6 -3.0 -3.0 -0.2 -1.1 -0.4 0.0

Wrecked/ Stranded

20.2 -0.5 -0.4 0.0 -1.5 -1.8 -1.8 -0.3 -1.0 -0.3 0.0

6 Wireless remote control from the lifeboat could be considered when the technology has been developed 7 As compared to current (The RCO is suggested as a further improvement of the Free Fall lifeboat)


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STEP 4 - COST BENEFIT ASSESSMENT The base case is described in detail in ANNEX II, and is summarized in Table 11. It should be noted that the success rate for evacuation in general and for the dominating foundering scenario in particular is very low. There are generous possibilities for improvement.

Table 11 Probabilities of Fatality Associated with Evacuation Accident Scenario Probability of fatality [%] PLL8

[per ship year] Collision 45.7 3.3610-3 Contact 44.1 1.1510-3 Fire/Explosion 27.7 2.3610-3 Foundered 55.4 1.4410-2 Hull/Machinery failure 16.2 5.1210-4 Wrecked/Stranded 20.2 2.4510-3 The costs relating to the proposed Risk Control Options include:

- Equipment costs

- Installation cost at the Bulk Carrier

- Inspection costs

- Maintenance or replacement costs - Costs of training to operate the equipment

Cost in the assessment thus relates to the present value of the life cycle cost of the RCO. Depreciation of future costs is carried out at a real9 risk free rate of return of 5%, as indicated in MSC 72/16. Benefits are the reduced number of fatalities. No explicit account has been made for reduced number of injuries or negative health effect. Further, it is considered that the RCOs relating to LSA have no other effect than life saving. The cost to benefit ratio are given in terms of Gross Cost of Averting a Fatality10 (GCAF), defined as:

Cost of RCO GCAF =

Reduction in PLL

where PLL is the potential loss of life (In statistical terms: The expected loss of life). The result is shown in Table 12. Marine evacuation systems that could be used for bulk carriers are under development by some manufacturers. The costs are not known. Table 12 therefore give what a marine evacuation system could cost in excess to a throw over board system to be just cost effective. 8 PLL = Evacuation frequency [23.7 Probability of fatality] 9 Real Rate of Return: Rate of return after correcting for inflation 10 Sometimes the Net Cost of Averting a Fatality is used. NCAF=(Cost of ROC Economic Benefits of RCO)/(Reduction in PLL). For LSA the GCAF is equal to the NCAF.


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Table 12: Risk Reduction, Costs and GCAF of the RCOs Cost Estimates GCAF RCO PLL

Low High Low High Recom- mended?

Robust Recom- mendation?

Sheltered mustering and Lifeboat area

0.00036 10,000 20,000 732,000 1,050,000 YES NO

Remote operation from muster area

0.00018 10,000 20,000 2,114,000 4,228,000 NO YES

Water level alarm 0.0038 14,000 21,000 146,000 218,000 YES YES Immersion suits to all personnel

0.0012 15,000 17,800 481,000 571,000 YES YES

Free-fall lifeboat 0.0015 -7,800 18,200 -214,000 499,000 YES YES Add free float mode for free- fall lifeboat

0.00036

5,000 7,000 551,000 771,000 YES YES

Free-fall lifeboat with free float mode11

0.0018 -2,800 23,200 -61,400 509,000 YES YES

Pick-up crane 0.00013 40,000 80,000 12.3 mil 24.6 mil NO YES Enclosing existing lifeboats

0.00044 4,000 6,000 906,000 1,359,000 YES NO

Redundant trained personnel

0.00015 8,000 10,000 2,053,000 2,566,000 NO NO12

Marine evacuation system for throw overboard liferafts

0.00017 4.40013 Criteria 1 million Not known

Not known

STEP 5 - RECOMMENDATIONS FOR DECISION-MAKING As basis for the recommendations it is observed that:

- The fatality rates for bulk carriers are high

- The success rates in evacuations are rather low

In ANNEX IV an analysis of two current LSA has been carried out:

- Conventional lifeboats

- Throw over board liferafts

The resulting GCAF is reproduced in Table 13. Since this is GCAF for decision previously made by IMO the figures represent an implicit willingness to pay for safety.

11 Replacing conventional 12 Dependent on training cost in different countries, which may be varying to a large extent 13 The maximum additional cost of a marine evacuation system as compared to throw overboard liferafts that would meat the criteria (costs are likely to be considerable higher).


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Table 13 Risk Reduction, Costs and GCAF of the RCOs

Cost Estimates GCAF RCO PLL Low High Low High

Two Conventional Lifeboats

0.01032 160,000 180,000 620,000 700,000

Throw overboard liferafts

0.00046 23,000 28,000 2.0 million 2.43 million

The implicit willingness to pay is thus in general agreement with figures suggested in MSC 72/16, and the previous decisions made by IMO are supported by this FSA, although the liferaft solution is not cost effective. The following RCOs are providing considerable improved lifesaving capability in a cost-effective manner:

- Free-fall lifeboats with an additional free float mode (New ships). This solution is slightly better that the free-fall lifeboat solution itself, which is also considered cost effective.

- Water level alarm with continuous water level indication in all holds and fore peak (New and existing ships)

- Personal immersion suits to all personnel (New and existing ships)

It is further noted that the success rate in evacuation from existing ships remains rather low also after implementing the suggested RCOs. This may call for additional measures, in particular focused on crew competence and training for these ships. Some Risk Control Options came out of the assessment as cost effective. Their contribution to life saving are rather small, and a recommendation to implement these RCOs is not robust due to the sensitivity of the results to assumptions and estimates made in the assessment:

- Protection of muster/lifeboat area (New and existing ships)

- Enclosing existing open lifeboats (Existing ships)

Further, other RCOs have been checked as clearly non-effective. The lack of effectiveness is more a result of small contribution to improving lifesaving than a result of excessive costs. 7 FINAL RECOMMENDATIONS FOR DECISION-MAKING The following Risk Control Options should be considered for implementation:

- Free-fall lifeboats with a free float mode (In SOLAS chapter III, regulations 31, 1.1 and 1.2)

- Water level alarm with continuous water level indication in all holds and fore peak, for new and existing bulk carriers (In SOLAS, chapter XII, regulation 11)

- Personal immersion suits to all personnel for new and existing bulk carriers (In SOLAS, chapter III, regulation 32, 3.2.)


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The free-fall lifeboat is strongly recommended for new ships. These RCOs are considered cost effective with a considerable improvement of life saving capability. For example, if all these three RCOs are implemented the risk assessment indicates that the success rate in evacuation in the dominating foundering scenario increases from less than to about 2/3. This improvement is considerable, but is still a low success rate. For existing ships the success rate will be lower. Dependent on the implementation of preventive measures that reduces the likelihood of the accident scenarios (e.g. proposed by other ongoing FSAs) other RCOs relating to life saving could be considered. The analysis is generic, and further RCOs may also be required if sub-groups of bulk carriers turn out to be associated with higher risk. LIST OF ANNEXES

ANNEX I : Hazard Identification, http://research.dnv.com/public/ANNEX-I.pdf

ANNEX II: FSA Step 2, Risk Assessment, http://research.dnv.com/public/ANNEX-II.pdf

ANNEX III: Free-fall Lifeboat as RCO, http://research.dnv.com/public/ANNEX-III.pdf

ANNEX IV: Other Risk Control Options, http://research.dnv.com/public/ANNEX-IV.pdf

ANNEX V: Willingness to Pay, http://research.dnv.com/public/ANNEX-V.pdf

ANNEX VI: RCO Meeting, http://research.dnv.com/public/ANNEX-VI.pdf

ANNEX VII: List of Credentials Short CVs, http://research.dnv.com/public/ANNEX-VII.pdf

ANNEX VIII: Review Meeting, http://research.dnv.com/public/ANNEX-VIII.pdf

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