Extension of the m-SHEL Model for Analysis of Human Factors at Ship Operation

Abstract

In order to understand how people respond to different circumstances, a classification system is required that specifies the knowledge and attitude of people and the effect of circumstances. In this paper, we propose a human factors classification framework to classify the seafarer's safety-related factors. The m-SHEL (Software-Hardware-Environment-Liveware with their management) model was adopted as a conceptual base of generic human factors, and extended to accommodate ship navigation domain. According to navigation practices, especially pertaining to collision and grounding avoidance, our model defines a detailed category for each of the m-SHEL interfaces. By counting the original m-SHEL interfaces as level 1, and by considering human factors that relate to the two types of circumstances, we have defined 13 specific categories descending from them as level 2 classification and 38 more specific subcategories as level 3. It is common to the navigational operations that ships are often involved in a circumstance of meeting other ships in traffic. However there are rather scanty direct communications among them, existence of approaching ships causes considerable influence on the operator. The framework therefore is intended to be applicable to the circumstances of being in traffic. To gain experimental data on critical situations related to collision and grounding, questionnaire surveys were carried out, and from the answers, operators' opinions about safe navigations and human factors are profiled according to the proposed classification framework. This paper provides an overview for human factors in two types of critical circumstances, i.e. collision and grounding avoidance, and an in-depth exploration of collision factors. Some statistical analysis and discussion on the profiles show that the relations between seafarer's attributes and safety attitudes are reasonable, and thus the proposed classification framework contributes to the understanding of human factors in ship operation.