Fight or flight – When to Initiate a Mass Evacuation at Sea?

on . Posted in General News

One of the hardest decisions a Ship’s Master will ever have to take must surely be the one to abandon a vessel with thousands of passengers onboard whilst at sea. So what should influence this decision and how much time do they have? Here Dave Sheppard, manager of the IMRF's Maritime Incident Response Group (MIRG) explains more:

 

Objective Decision Influences

Much of the decision making process could be considered as objective with sound technical guidance and advice used in the design and implementation of the evacuation process. This is underpinned within SOLAS Regulation III/21.1.4 that requires all survival craft shall be capable of being launched with their full complement of persons within a period of 30 minutes from the time the abandon ship signal is given. However, this regulation stipulates that the 30 minute timeframe only starts when all the passengers have been mustered with lifejackets donned.

In addition MSC Circular 1533 provides an evacuation analysis tool that recommends a maximum allowable total passenger ship evacuation time to be in the range of 60 to 80 minutes dependant on the number of main (fire) vertical zones:

60 minutes: Applies to ships having no more than three main vertical (fire) zones
80 minutes: Applies to ships having more than three main vertical (fire) zones

The analysis tool contained in MSC Circular 1533 sets out an evacuation model that is broken down into key stages:

  Awareness time (A)* which should be 10 minutes for night time and 5 minutes for day time.
Travel time (T)*
Embarkation time (E)*
Launching time (L)*

*See footnote for definitions

These parameters are brought together in a formula to identify the total evacuation time (n):

Calculated total evacuation time (n) = 1.25 (A + T) + 2/3 (E + L) ≤ n

Additionally the Master will know that there are a number of safeguards designed into the vessel, such as fixed installations and compartmentation that will provide a degree of protection. For example a Class A bulkhead will provide a minimum of 60 minutes protection from fire and a Class B bulkhead 30 minutes of protection.

 

Subjective Decision Influences

It is absolutely correct that the vessel remains the best liferaft the Master is unlikely to know with any certainty the length of time that the vessel will retain its integrity prior to becoming a hazard in its own right. This variable will be influenced by a range of factors, many of which the Master may never have experienced previously.

The Master has the ship’s crew who they can use to try and mitigate the cause of the situation e.g. fire teams that may be able to deploy to resolve or contain any situation. The challenge for the Master in this scenario is that it will take time to understand whether or not the intervention is working and that time delay may prove critical in terms of being able to complete a ‘successful’ abandonment.

Further the Master has the ability to be able to weigh up all options based on what the objective data is telling them and come to a more considered answer based on their training, knowledge and experience although this does also introduce a whole range of variables based on the Master’s critical decision making ability.

The risk with all of the above is that the critical thinking time required to make the decision will be using up part of the total evacuation time and may lead to an increased level of risk for the passengers and crew if the abandonment time then exceeds the survivability duration of the vessel.

The Master will also have to consider whether the provision of external assistance might be available to the vessel within a timeframe that is able to influence their decision e.g. can sufficient SAR resources be on scene to manage the evacuees or can additional resources be brought to the vessel to contain the situation on board but again this consideration features a number of variables that require consideration.

 

Conclusion

Whilst the current evacuation analysis contained in MSC Circular 1533 is clear and carefully considered around the elements of objective decision influences there may be a case some additional work around the subjective decision influences as these have the potential to lead to an extension of the total evacuation time. This risks exceeding the survivability of the vessel and exposing the passengers and crew to an increased risk.

However ultimately it must always be remembered that the decision of whether/when to abandon or remain on the vessel is probably best categorised as ‘consequence management’ because either outcome has the potential to cause harm. All the Master can seek to do is mitigate that harm as far as reasonably practicable. Others will judge any decision taken but they will have the two great advantages of using hindsight and not having to make the often unenviable real decision themselves.

For information on this, and other MIRG topics, go to http://imrfmirg.org.

 

Footnote

Awareness time (A) is the time it takes for people to react to the situation. This time begins upon initial notification (e.g., alarm) of an emergency and ends when the passenger has accepted the situation and begins to move towards an assembly station.

Travel time (T) is defined as the time it takes for all persons on board to move from where they are upon notification to the assembly stations and then on to the embarkation stations.

Embarkation time (E) and launching time (L), the sum of which defines the time required to provide for abandonment by the total number of persons on board and must not exceed 30 minutes.

APRC Contact

International Maritime Rescue Federation
Asia Pacific Regional Centre
Donghai Rescue Bureau
Room 405
No. 1426 Yang Shu Pu Road
Shanghai
200090
China

E-mail: admin.aprc@imrf.asia
Telephone: +86 21 55 09 53 01

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