### Significance  
The abovementioned three terms have different origins. \"Human element\" was introduced by the IMO in the 1990s [1] to cope with human influence in the maritime domain. Its background implies that it is a domain-specific term. The term \"human factor\" has been used since World War II, and it is an interdisciplinary subject involving psychology, sociology, engineering, physiology, biomechanics, anthropometry, and user interface design [12]. The term \"Human factor\" has been utilized in various fields; thus, it differs from \"human element\" because of their different backgrounds. \"Human error\" first appeared in journal articles in the 1960s. It followed a path of \"topic after working (the 1970s)-concept during working (the 1980s)-central of the human factor (the 1990s)\" [13].  
\"Human factor\" and \"human error\" were not initially developed in the maritime domain, but have been recently adopted. The IMO adopted the term \"human element\" for use in the maritime field but did not differentiate the three terms properly. The mix-up in the use of the three terms has become common in research articles such as that conducted by [PERSON] et al. [14] who evaluated the human factors influencing maritime accidents, while human error appeared throughout the article. Other studies have shown a similar situation [15; 16; 17]. However, some scholars have addressed this confusion, noting that it could compromise the accuracy of human reliability assessment (HRA) [10; 11; 18]. Other scholars have distinguished between \"human factor\" and \"human error\" [19]. Unfortunately, research on the similarities and boundaries among the three terms is limited. This may be because only a few studies have considered differentiating among the terms to avoid complications [18]. However, the necessity to correctly identifying each term depends on the development, pain points, and future trends in the maritime domain. Since the implementation of the ISM code, the \"human factor\" has been a research focus, with an increasing number of human-related articles, dissertations, and conference papers published. If we just assume that the three terms express the same meaning, then one might misunderstand the authors' intentions or the meanings they are attempting to express. For example, one study [20] claimed that marine causalities or safety incidents caused by  
Figure 1: Accident events affected by human element.  
human factors might not be because of human error but because of internal pressure. For pain points, numerous maritime accidents are related to human factors (EMSA report), indicating that the human factor remains a pain point in the maritime safety field. For future trends, it will likely be divided into manned and unmanned navigation. For manned navigation, similarly to present navigation, human factors will remain an important issue. For unmanned navigation, the vessel will be driven automatically or controlled remotely by shore-side drivers. In remote control situations, research has shown that human error remains the main factor influencing navigation safety [19]. Automatic navigation could reduce the chance of manual operations, thus minimizing navigational accidents (e.g., grounding, collision, and contact), but non-navigational accidents (e.g., fire, blackout, and cyber security hijacks) will increase significantly compared with manned ships [20]. Moreover, human error will still exist in the design stage or the operational period [21]. Therefore, it is necessary to distinguish the three terms.