Ship evacuation in response to fire or flooding hazards involves two phases: mustering, that is movement of people away from a designated area to a safer area or to the muster stations and abandoning the ship (embarkation and launching lifeboats). Evacuating a large and complex environment such as a large passenger ship is a safety- critical and strictly time-bound task, which typically involves thousands of people moving within parts of the ship, assisted by a significant number of crew personnel, and a complex decision-making process based on the evolving situation on-board and the information available to the decision makers. Timely mustering and abandonment requires fast and accurate evaluation of ship’s conditions as well as estimation of remaining time. The assumption that all these people will be able to comprehend and follow instructions or even that the crew will be able to communicate verbally during a crisis is very optimistic. In response, a system that will provide clear instructions and guide passengers safely on how to react in an emergency situation without reliance on any passenger skills or experience is of paramount importance for any large passenger ship you are.
Managing an evacuation in real time. In most cases, evacuation plans insufficiently address the actual challenges of an evacuation, particularly in the presence of flooding and fire hazards and in extreme environments. Similarly they fail to adequately account for human behaviour during stressful situations and lack of resilience. Current International Maritime Organisation (IMO) evacuation guidelines relate to day and night scenarios in calm water and in the absence of any additional hazards. Similarly, damage control plans and evacuation plans are static, failing to effectively manage situations that evolve and change over time (ship’s trim and list, fire and flooding propagation, etc.). Thus, real-time, dynamic management of the evacuation process is critical in marine accident response. The situation with Life-Saving Appliances (LSA), including Mass Evacuation Systems (MES), is even more worrying. Abandoning megaships with up to 10,500 people on-board (the latest designs) is currently only an afterthought (current rules specify a period of 30 minutes for abandonment). Furthermore, considering that current ship designs are not adjusted for facilitating evacuation imposing delays within the evacuation process, a complete re-thinking of LSA and associated ship designs is of paramount importance. In this respect, capturing the situation properly and including dynamic information in an efficient way is critical for achieving i) rapid response, ii) timely guidance and iii) safe evacuation of all persons on board. As indicated above, the algorithms in use today by evacuation modelling software, in response to the existing rules, only calculate the movement time, based on the maximum “flow” of the crowd, which is only one part of the evacuation time equation. Therefore, the IMO regulation development process needs to be revisited and supported to target relevant, fit for purpose regulations. With such developments in place, risk models of the whole evacuation phase, from ALARM to RESCUE could be developed and tested, enabling for identifying new cost-effective risk mitigating and control options. This will facilitate the healthy evolution of all LSA and a cost-effective approach to managing and mitigating evacuation risk in emergencies.
Current regulatory provisions. IMO SOLAS Chapter II-2, Part D, Regulation 13 – ‘Means of Escape’, as it was amended under Resolution MSC.404(96) makes evacuation analysis a mandatory requirement for new passenger ships constructed (keel lay date) on or after 1st January 2020, when carrying more than 36 passengers. It recommends the use of MSC1/Circ. 1533, which provides the Revised Guidelines on evacuation analyses for new and existing passenger ships. These guidelines offer a simplified and an advanced method for conducting the evacuation analysis. The input for the simplified method was based on measurements of people movement in land buildings which share physical similarities (dimensions, reproducible light conditions) with ship evacuation. Unfortunately, the operational requirements of passenger ship evacuation are not equivalent to those of buildings on land – e.g. the behaviour of the people involved - which has led to many experts criticising the current guidelines. In addition, extreme conditions, fire and flooding hazards render the current regulatory instruments insufficient.
Regarding the LSA, they are covered by SOLAS Chapter III and the LSA Code. This prescribe the requirements for lifeboats, rescue boats and lifejackets etc. according to the ship type. Acknowledging the constraints created by the existing prescriptive requirements, in particular regarding large cruise ships, in 2009 IMO opened the Alternative Design and Arrangements (AD&A) path for novel solutions that offer the same level of safety and performance with the prescribed ones. However, AD&A does not address existing concerns with respect to adequateness of the prescriptive regulations, at least, for passenger ships. Currently, IMO is developing functional requirements for life- saving appliances in compliance with MSC.1/Circ.1394/Rev.1, but these will provide only the background for existing provision and no improvements are considered. Against this background, IMO agreed a new work item on the revision of SOLAS chapter III and LSA Code (MSC 98) based on the Goal-Based Standards-Safety Level Approach (GBS-SLA). This work shall be commenced after the functional requirements will become available. Both the AD&A and the GBS-SLA are based on risk-based methods, underlying the importance of a complete and transparent risk model which supports the development and implementation of innovative evacuation and LSA systems onboard.