Evacuating a large and complex environment, such as a large passenger vessel, either cruise or RoPax, is a safety-critical task that involves thousands of people in motion and a complex decision-making process. Despite the significant enhancement of maritime safety over the years, various hazards still pose threats to passengers and crew. To deal with this reality, the SafePASS project radically redefines the evacuation process by introducing novel technological solutions. In this context, this paper presents, in detail, an enhanced risk model for the ship evacuation process in order to facilitate the understanding of the actual risks of the process in fire and flooding accidents, and to assess various risk control measures and options toward risk mitigation. The risk model covers the entire event sequence in emergency cases on board, until the survival at sea phase, and it is constructed in two levels, following a combination of event tree analysis and Bayesian networks. Results show the risk corresponds to baseline scenarios for each accident case, which are also verified by relevant IMO and EMSA studies, and an example case of risk control option (RCO) is introduced to the model to demonstrate its ability to assess RCO’s efficiency in terms of risk reduction.
The wide spread of the Diesel engine has been instrumental in the development of modern shipping. Marine Diesel engines dominate today as an option for the propulsion of commercial ships. While replacing Diesel engines with alternative propulsion engines is difficult to achieve, companies, in light of the new EEXI regulations, are turning to improvements, such as operating at lower rotational speeds, higher maximum combustion pressures, and more efficient overcrowding systems. Τhe purpose of this research paper is (i) to present the basic operating principles of marine Diesel engines, (ii) to study the main differences between electronically controlled Diesel engines and their mechanically controlled counterparts, and (iii) to evaluate their performance under newly introduced IMO’s EEXI regulations. Thus, after comparing Wärtsilä RTA and WinGD WX, the paper concluded that WinGD WX, being electronically controlled, will perform more effectively under new EEXI regulations, as it offers (i) reduced fuel consumption in low-load mode, (ii) zero-smoke emission at all operating speeds, (iii) very stable operation at low speed, (iv) more straightforward engine setup leading to less maintenance, (v) more extended periods between maintenance, mainly due to better load distribution between cylinders and more perfect combustion. From a regulatory perspective, the new limitations installed by the newly implemented EEXI and CII regulations will cause fewer implications in electronically controlled engines, while from an economic standpoint, the electronically controlled engines decrease OPEX and require fewer personnel, due to their efficiency at low loads and overall flexibility.