Analysis of the human factor contribution to the risk of navigation in restricted waters.

• Autor(a) principal: Danilo Taverna Martins Pereira de Abreu
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: https://doi.org/10.11606/D.3.2021.tde-30082021-150544

The navigation in restricted waters presents a number of additional challenges when compared to open sea navigation. The reduced size of waterways, congested waters and the dynamics of obstacles such as underwater shoals make the port entering and departure and river navigation prone to accidents, such as collisions, contacts and groundings. Additionally, restricted water navigation is performed without the support of automated control systems, which makes it significantly dependent on the performance of the human operators involved, such as maritime pilots, the captain of the ship with his/her crew, and the tug masters. Notwithstanding the risks inherent to the restricted water navigation, commercial pressure forces safety margins to their limits. The effect of the gain of scale causes larger ships to reach ports which, in turn, often cannot adapt their access channels to the demand. As a result, human operators are responsible for ensuring the safety of the navigation even when the safety margins are reduced.Given the importance that human operators play today in restricted water navigation, it is interesting to know which key factors influence their performance in order to ensure high levels of human reliability. In this context, this work aims at the development and application of the Human Reliability Analysis to investigate how the human factor contributes to the risk of restricted water navigation and which are the main performance factors that affect the probability of human error. The analysis is based on a Bayesian network model (quantitative), which maps the causal relationships between the tasks performed by operators and their necessary skills, as well as internal, environmental, and organizational factors. The analysis is developed for three different scenarios: a) with one Pilot on board; b) with two Pilots on board; and c) without Pilot on board (pilotage exemption). The quantification of the model is performed based on the probabilities of human error derived by a prospective human performance model - the Technique for Early Consideration of Human Reliability (TECHR).The results include a ranking of the factors that most influence the operators in each case, which is generated from a comparative analysis of human error probabilities in different scenarios and a network sensitivity analysis. Among other things, the results reveal the importance of ensuring the fitness for duty of human operators in what refers to knowledge of local conditions through continuous work reinforced by laws and training, as well as the need for good coordination of the crew on board.