Study On The Cause Analysis And Intervention Strategy Of Crew Fatigue In Marine Accidents

The human factor is an important reason for inducing maritime accidents.As a typical human factor,crew fatigue has an important impact on the navigation safety of ships.According to statistics,11%～25% of ship collision or grounding accidents are related to crew fatigue.Under the coupling influence of reduced crew staffing level,increased workload,and complex and changeable navigation environment,it is easy to cause crew fatigue of sailing ships,and then lead to the occurrence of maritime accidents.Therefore,it is necessary to conduct an in-depth analysis of the causes of crew fatigue inducing maritime accidents,so as to propose specific intervention strategies.The current research on crew fatigue mainly focuses on the analysis of single or multiple fatigue influencing factors,and there are few studies on the causes of crew fatigue,possible accident risks and intervention strategies from the systematic level.Aiming at the problem of crew fatigue inducing maritime accidents,based on the global maritime accident investigation report and crew questionnaire survey,this dissertation is based on the research idea of "Analysis of the causes of ship fatigue inducing maritime accidents--simulation of the evolution process of crew fatigue--effectiveness analysis of crew fatigue intervention strategies".The problem of crew fatigue inducing maritime accidents has been researched by using Bayesian Network,Functional Resonance Analysis Method(FRAM),Monte Carlo Simulation(MCS),scenario analysis,etc.This study can provide a basis for relevant decision-making departments or sailors to mitigate and prevent fatigue,to prevent or reduce maritime accidents and effectively avoid casualties and property losses.The main research work of this dissertation is as follows:(1)Research on the identification of influencing factors of crew fatigue inducing maritime accidents.Through sorting out the relevant factors that induce sailor fatigue,the key influencing factors that are most likely to induce sailor fatigue are identified.Based on the questionnaire and relevant data of historical maritime accidents,the relevant process of how fatigue causes accidents is further explored,and the relevant influencing factors that cause sailor fatigue and then lead to accidents are identified under the circumstances of maritime accidents.The results show that,among the causes of maritime accidents,improper lookout,inadequate communication and cooperation and poor safety management are the important factors causing accidents.Among the causes of fatigue,psychological factors have a more significant impact on crew fatigue.From the perspective of fatigue inducement,continuous long hours of work and high-intensity workload are the key physiological factors causing crew fatigue.Suffering from high working pressure,being alone on duty at night and boring work are the most likely to cause the psychological factors of crew fatigue.(2)Analysis of the cause-chain of crew fatigue that induces maritime accidents.Based on identifying the influencing factors of crew fatigue,the Bayesian network method is used to analyze the formation path of crew fatigue that induces maritime accidents,and the cause chain of crew fatigue is studied combined with sensitivity analysis.The results show that continuous long hours of work and high-intensity work pressure are the main causes of crew fatigue,followed by high-intensity workload,alone on duty at night and boring work.Among them,highintensity work pressure,night alone duty and boring work will lead to poor psychological condition,continuous long hours of work and high-intensity workload will lead to poor physiological state;The main causes of grounding accidents are as follows: equipment failure→ deviation from course → grounding accident,crew fatigue → improper lookout → grounding accident,crew fatigue → error in judgment → grounding accident,lack of training →inexperience → error in judgment → grounding accident;The main causes of collision accidents are as follows: poor safety management → inadequate communication and cooperation →collision accident,crew fatigue → improper lookout → collision accident,low visibility → unsafe speed → collision accident,crew fatigue → error in judgment → unsafe speed → collision accident.(3)Analysis of the evolution process of crew fatigue based on FRAM-MCS.Based on the analysis of the cause chain of crew fatigue,the evolution process of crew fatigue was analyzed by using structural functional resonance analysis method(FRAM)and Monte Carlo simulation method(MCS).The results show that in grounding accidents,sleep disorders are likely to lead to crew fatigue.It may be more effective to reduce the occurrence of grounding accidents by improving the evolutionary path of sleep disorders caused by the linkage factors of high-intensity workload,continuous long-time work and high-intensity work pressure.In collision accidents,the sleep disorders caused by high-intensity workload and continuous long-time work is the path with the highest resonance degree,which will dramatically amplify system fluctuations.The resonance effects of sleep disturbance caused by continuous long hour’s work,high-intensity work stress caused by high-intensity work load,disturbance of circadian rhythm caused by alone on duty at night are also likely to amplify the risk of system.(4)Study on the intervention strategies of crew fatigue inducing maritime accidents.Based on the identification of marine accident cause chain,the evolution path of seafarer fatigue,the calculation of marine accident occurrence probability and the analysis of fatigue intervention measures,a Bayesian network model of the fatigue intervention strategy of seafarers induced marine accidents was constructed.According to the change of risk probability in the model,the effects of single and combined intervention strategies on crew fatigue,crew fatigue in grounding accident and crew fatigue in collision accident were analyzed.It is found that,in a single intervention strategy,reasonable staffing level is the most effective intervention measure,which can significantly reduce the probability of crew fatigue and maritime accidents.In the combined intervention strategies,the reasonable staffing level,scientific task allocation,lighting management and sleep management can effectively reduce the fatigue of the crew,the probability of marine accident,grounding accident and collision accident is reduced to 95%,94%and 97% of the original level respectively.