Prioritization of the causal factors of fatigue in seafarers and measurement of fatigue with the application of the Lactate Test

Despite the developed technology and numerous rules introduced for the purpose of reducing the effects of human error on marine accidents, human error remains as the greatest cause of the accidents. A great majority of the accidents occur due to human error caused by fatigue. Human fatigue is difficult to measure and even more difficult to state as a cause to an accident. Therefore, conducting studies on the causes of fatigue and fatigue levels of seafarers is important in terms of emphasizing on the effect of fatigue in marine accidents. In our study, the factors that cause fatigue on seafarers were examined analytically and their quantitative priorities were determined through the use of the Analytic Hierarchy Process (AHP) method. In addition, lactate Test as an objective method to measure fatigue was used to indicate the fatigue levels of seafarers. Lactate data, commonly accepted as the most significant indicator of physiological parameters, were collected from seafarers at different times and in actual marine conditions. Obtained data were analyzed in SPSS software and Exploratory Data Analysis (EDA) was applied. Examining AHP results shows that sleep has a substantial role on the occurrence of fatigue in seafarers. According to the results of Lactate Test, it was determined that seafarers are generally highly fatigued and the fatigue levels increase particularly during port calls. In conclusion, the purpose of this study is to determine the fatigue levels of seafarers and to set forth the quantitative prioritization of the factors causing fatigue. (C) 2014 Elsevier Ltd. All rights reserved.