In the maritime setting, a mass casualty incident (MCI) can be defined as an event where the number of casualties vastly exceeds the on board healthcare capabilities in a short time period. Any MCI can rapidly exhaust available resources, not only to manage the MCI but also to maintain the normal operations of the ship. The number of casualties does not need to be high in itself, but enough to exceed the available resources.
Various events in the past, such as the fire on the Lisco Gloria ferry, the disaster at the Costa Concordia, the fire on board the ferry KM Karya Indah or the collision of a container ship with a building in the port of Genoa show that mass casualties in the maritime environment can occur at any time and affect a large number of people. The corona pandemic particularly affected cruise ships. While there are tested operational concepts for such situations on shore, this is often not the case for the sea and port sector. The research project KOMPASS, funded by the Ministry of Education and Research in Germany, has reviewed this topic.  and the project consortium of experts from the maritime and medical sectors has developed proposals on how to effectively process a MCI at sea.
H.4.2 Types of mass casualty incidents at sea
In the past, major ship incidents often resulted in the immediate abandonment and subsequent sinking of the ship. However, with the increase in cruise shipping worldwide and improved management of incidents on board all types of vessels, various situations may and have occurred which can lead to a proportionately high number of injured people without shipwrecking. These include:
- Fire onboard - burns and inhalation of smoke or toxic gases
- Explosions – burns and inhalation of smoke or toxic gases, amputations, blast injuries,
- Collisions, heavy sea - fractures, bruises, internal injuries
- Flooding, unprotected stay – hypothermia, drowning
- Infectious disease - vomiting, diarrhea, fever, respiratory outbreaks , 
- Terrorist attack - bullet wounds, blast injuries, mental health issues
- Embarkation of casualties from another vessel, including refugees
In such a case, injured or ill persons must be cared for directly on board with the means available until further assistance arrives. Additional information on many of these situations is available elsewhere in the Textbook
H.4.3 Additional challenges at sea
If dealing with a mass casualty incident ashore poses a great challenge to the various helpers, further challenges occur on board a ship   :
- There are a limited number of medically qualified personnel available on board. According to the Maritime Labour Convention (MLC) 2006 , only a vessel with 100 or more persons on board and ordinarily engaged in international voyages of more than three days’ duration must have a doctor on board. On ferries, which may have several hundred passengers, but are on shorter routes, usually a nautical officer is responsible for medical care although some companies do have a health care professional, for example a paramedic, on board. On normal merchant vessels medical care is provided by a nautical officer with limited training . More information on the medical training of seafarers is available in Ch 5.3. Only on cruise ships can it be assumed that a doctor and qualified nurses are on board, although some ferry companies do carry health care professionals, for example a nurse or paramedic.
- The ship’s crew has to cope with the MCI alone, often for several hours. At the same time, they must also restore or continue the ship’s operation.
- External assistance will reach the affected ship after some time and often only in limited numbers and capability. The time taken depends on many factors, including the location of the ship, the sea and weather conditions and the availability of appropriate resources.
- There is a high risk to the assistance providers themselves. This includes the risks of helicopter operations, boarding the affected ship from another vessel, the list of the vessel and fire etc. on board. Bad weather may increase the risks yet further.
- Basic services that are easy to obtain on land may not be available. Depending on the nature of the accident, important supply systems such as electricity, water supply or the operation of sanitary facilities may have failed. An immediate repair or replacement is not always possible.
- It is difficult to orientate oneself on a large passenger ship with its many decks and stairways. In an emergency, when the ship is possibly listing to one side, orientation becomes even more difficult, when formerly horizontal passageways suddenly become vertical shafts. Passenger services staff should be stationed at stairways and other points around the ship to direct passengers as required.
- The available space, already restricted on a ship, may be further limited by the accident and it may be impossible to reach some areas.
- Persons on board who require medical care may be hard to reach and cannot be transported quickly to hospital.
H.4.4 Risk management
Every ship should have a procedure to handle a MCI within its Safety Management System (SMS). The details of the response plan will vary depending on many factors including but not limited to:
- Size of the vessel
- Number of crew and passengers on board
- Expertise on board
- Sailing area
- Access to additional assistance
The response plan should be clearly documented, communicated to the seafarers on board and practiced in appropriate drills. As in all emergency response procedures, all relevant roles and responsibilities at a mass casualty incident at sea should be defined in the muster list.
Essential roles, with specific responsibilities include:
- General Head of Operations (usually the Captain)
- Internal Communication
- External Communication
- Search and Transport
- Medical Care
- Passenger Care
Further information is given below and depending on the number of additional staff available, further roles can be defined. All tasks should be laid down in the job description of every crewmember and the seafarer should be familiar with the tasks involved, before the MCI happens.
H.4.5 Provision of MCI equipment
As outlined above, a number of scenarios can result in MCIs. It is impossible to guarantee an extensive provision of onboard resources for all eventualities but in order to optimise the response it may be useful to have access to and use:
- vests in different colors and with the respective function written on them, for example, “Transport”, “Medical Care”, “Logistics”, “Assistance” and “Communication”
- equipment to support the preparation and identification of treatment areas such as colored barrier tape or similar, moveable walls, appropriate signage
- pre-fabricated blank signs to write on with a possibility to hang to ensure they are visible
- a triage system for the assessment of casualties appropriate to the knowledge and experience on board.
- forms to easily register casualties not requiring immediate medical care
- rescue and essential first aid equipment at multiple locations on board
Such equipment should be included in the SMS and every seafarer on board should know where the MCI equipment is stored.
H.4.6 Determination of appropriate areas for the treatment of casualties
- The ships SMS should state the areas designated for the reception and treatment of casualties. As space on board is limited and the movement of injured people around a ship is difficult, the location of such area(s) should be carefully considered and must take account of the following aspects.
- It must be possible to quickly clear any furniture in the area in order to ensure there is enough space to accept several casualties at the same time. The maximum number of patients the treatment area can accommodate should be marked in the SMS. If several treatment areas are available onboard, a sequence of occupancy should be agreed.
- The area should be easily accessible, even for stretchers and wheel chairs. If possible, the entrance and exit routes from the area should be different.
- Interior rooms are preferable to provide a private area protected from the elements. However, at least one treatment area should be identified on open deck in case of smoke or fire inside.
- It should be possible to divide the location into separate areas without blocking other access points or passages.
- Running water and electricity should be available nearby. Rest rooms should be easily accessible.
- A safe communication with ships command should be possible.
- The evacuation site (e.g. helicopter deck) should be easily accessible.
For infectious diseases, ideally it should be possible to decouple the ventilation system of the treatment area from the main system and to ventilate the treatment area independently. Appropriate ventilation controls should be installed and regularly tested. It should also be possible to install a double door system at the entrance to the treatment area. Once identified and treated, infected people on board should be isolated in an appropriate area as soon as possible.
H.4.7 Specific roles and responsibilities
For the management of an MCI on board, the following roles and responsibilities should be identified and allocated to specific positions on board as part of their emergency duties. These are in addition to other emergency duty teams such as firefighting, stretcher party etc. This should be part of the response plan and contained within the SMS.
Head of Operations
Usually taken by the Master, this role involves ensuring that the ship remains a safe platform whilst also managing the MCI. It also includes the safeguarding of the approach of other helping vessels or the landing of external assistance by helicopter. The Head of Operations is ultimately responsible for all of the key decisions on board.
Head of Internal Operations, Internal Communication (Bridge)
Usually taken by a deck officer this role involves managing communication on board the ship. It includes ensuring clear communication with the leaders of the various emergency response teams on board and
- creating regular situation reports summarizing the information of all teams to support the Master and the Head of external communication
- forwarding or distributing specific information to each team regarding the safety of the vessel, the on board situation, expected internal and external assistance.
- distributing specific tasks to each team regarding the provision of resources, transport of injured persons, caring for (unaffected) passengers
The role also involves clear communication to any passengers on board including:
- a regular, calm but informative description of the on board situation and summary of the current management and planned actions to be taken
- an announcement to request medically skilled passengers and other volunteers to support the ship’s crew if required
- an announcement of the appointed treatment area and request for all injured persons to go and register there if possible
- an announcement of assembly points for passengers looking for their relatives or needing other assistance
Head of External Operations, External Communication (Bridge)
Usually taken by a deck officer, this role involves communication with external parties such as the Maritime Rescue Coordination Centre, local authorities, shipping company and external assistance such as helicopters or other ships. Essential information to be relayed between the ship and others includes
- regular reports on the situation on board as provided by the Head of Internal Operations
- the need for assistance such as transport for injured persons, medical equipment and supply goods
- regular reports on the availability, timelines, amount and capability of external assistance to support the Head of Internal Operations and the Master.
- Information on casualties evacuated from the ship and recording of personal data of persons handed over.
Search and Transport team
The search and transport team(s) locate casualties and transport them to the appropriate treatment area. If several teams are available, the areas to be searched must be clearly defined. Depending on the type of incident, suitable personal protective equipment must be worn, for example, helmets and breathing apparatus. It is important to perform a systematic search and to mark the already searched areas so there is no need to re-enter an area.
Responsibilities of the team include:
- removal of obstacles in the search area
- location of casualties within the search area
- questioning of casualties to find out if there are further potential casualties nearby
- assisting a casualty out of the area and ensuring appropriate transportation to the treatment area or other appropriate muster point
- appropriate hand over of casualties to the medical team or other appropriate personnel
- providing regular updates on the number and conditions of casualties located to the Head of Internal Communication
- regular comparison of a list of missing persons with casualties located
As the situation develops the search and transport team may also be responsible for the transport of patients to external assistance, for example, to the helicopter winch area.
At the start of the MCI this team is responsible for identifying and preparing the treatment area. The location of appropriate treatment areas should be included in the SMS although some may not be suitable given the type and location of the incident that has occurred.
The preparation of the treatment area can include:
- removal of furniture
- ensuring there is sufficient room to accommodate a number of casualties on stretchers
- preparation of different areas, labeled appropriately according to the triage system
- laying out of blankets / sheets / towels to indicate places for casualties
- setting up of privacy screens (rows of chairs, curtains, moveable walls, …)
As the incident evolves the team is also responsible for the general logistics including:
- gathering information to provide an overview of
- all auxiliary equipment such as wheel chairs, stretchers, defibrillators and medications and their location
- the possibility to use telemedicine
- transferring of auxiliary equipment, medications etc to the appropriate treatment area or to several treatment areas as required
- provision of blankets, coolants, towels, sick bags, water, alcohol (for disinfection), beverages, food, lighting and tools where required
- regular collection and suitable disposal of waste
Communication with other teams is key to ensure that the correct equipment is available where and when it is needed.
Medical Care Team
This team triages the casualties arriving at the treatment area using a known triage system . In addition, it has the responsibility to complete the following tasks:
- appropriate labelling of casualties according to previous triage
- numerical recording and documentation of all casualties, and, when appropriate, recording of their personal details
- administering immediate care and first aid to casualties according to the triage priority
- requesting medical evacuation of casualties as required
- maintaining an overview of the medical equipment and other supplies used and request additional items as required
- clinical waste management
- preparation of casualties for hand-over to external assistance services
- involving medically trained passengers as appropriate
- ensuring communication to relatives of the casualties if possible
- providing regular updates to other teams and to the Head of Internal Operations
H.4.8 Passenger Care Team
On board a passenger ship, the physically uninjured passengers must be cared for during and after a MCI and this team is usually made up of passenger service staff. The relatively confined space of a ship means that it can be difficult to distance passengers from the incident and there is a high risk of secondary incidents, such as jumping overboard of emotionally distressed people.
Regular announcements with clear information and requests can go a long way to reassuring passengers and crew on board and providing a feeling of safety and confidence in the actions of the ship’s crew. Passengers should not be left in uncertainty and regular information about the extent of the emergency and adopted measures are essential.
- be given as early as possible in language(s) understood by passengers.
- be spoken loud and clear in short and precise sentences.
- be limited to the main essentials.
- not contain assumptions or contradictions.
- if possible be associated with a positive operational objective to be achieved next in order to provide hope and motivation.
- be repeated regularly.
- be connected with instructions where applicable. The compliance with given instructions often takes the burden off passengers to make their own decisions.
Other measures that are the responsibility of this team include:
- providing contact by sight or by voice to all passengers
- clarifying the current situation and most importantly, when the danger is over
- listening to and giving the opportunity to express their concerns and emotions
- providing food and beverages, blankets etc.
- providing time for rest and advising to sleep
- giving information to relatives about the current situation of their injured loved ones
- dividing people into smaller groups at different locations around the ship
- bringing together families, travel groups, friends
- registration of missing persons
Involvement of Volunteers
In the case of a MCI on board the number of crewmembers may not be enough to fulfill all the tasks required. Therefore, one of the first acts may be to identify suitably trained and willing passengers and assign them specific tasks as outlined in the ship’s SMS.
Announcements should address the volunteers, explain the skills sought and give assembly points. Passengers may be able to assist with skilled tasks, for example, the delivery of medical care or more general and administrative tasks that may include:
- clear up of damaged areas, for example after severe weather
- preparation of treatment areas to care for uninjured persons and relatives
- registration of missing persons and relatives
- transport and distribution of of beverages, food, blankets, equipment etc.
- supervision of injured or confused casualties
- securing areas which should not accessed by unauthorized persons
- assistance with the movement of casualties with minor injuries
Before tasks are assigned to volunteers, they must be assessed as being physically and mentally fit for the task.
Each ship should have a structured response plan in case of a MCI and this should be part of the ship’s SMS. This includes the assignment of tasks, the storage of necessary equipment to support the handling of a MCI and the identification of treatment areas
In a MCI at sea, the ship’s crew must handle the situation without external support, sometimes for many hours. This requires the seafarers to manage the incident in addition to the restoring the safe operation of the ship. The response to a MCI involves many teams and although regular training is required for firefighting, dealing with an ingress of water etc., this is not currently the case for the management of a MCI. Such training, including drills on board, would improve the response to a MCI in the maritime environment.
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