The construction industry is a disaster-prone industry, which accounts for about 50% of all industrial accidents, and the frequency of construction equipment use is increasing due to the large size and high-rise of structures in domestic construction projects, and the possibility of serious accidents is increasing, and in the event of a disaster, it is characterized by high intensity and high human and material losses. Despite existing research to solve these problems, construction machinery accidents have not decreased at construction sites, and this study aims to identify the cause of the accident by dividing the cause of the accident into four categories, examining the results, and contributing to the establishment of basic data to establish measures to prevent future construction accidents.
 This study is composed of five categories and I. In the introduction, research background, purpose, scope of research, and research method were presented, and II. In the theoretical consideration, H. W. Heinrich's 1959 theory of accident chain reaction, F. E. Fird's latest theory of disaster chain, construction machine accident cases, and prior research, III. The research method consisted of research questions, research hypotheses, operational definition of variables, composition of measurement tools, and surveys, IV. In the analysis results, general characteristic analysis, correlation, hypothesis verification, V. Through the conclusion, the test results were recorded and the direction setting of the limitations of the study and the impact of the four elements (4M) of future safety on excavator accidents was presented.
 <Table 7> shows how 'the four elements of safety (4M) affect excavator accidents at the construction site, which is a research problem, and the effects of Man (t=0.914, p=0.361) and Media (t=0.200, p=0.841) on excavators were not found to be significant. Accordingly, '[Hypothesis 1, 3] Human and environmental factors at construction sites will affect excavator accidents.' was rejected, and the effects of Machine (t=3.527, p<0.001), Management (t=5.988, p<0.001) on excavators have a significant impact, and accordingly, '[Hypothesis 2, 4] mechanical and management factors will affect excavator accidents at construction sites.'The research hypothesis 'was adopted.
 In the excavator accident, mechanical factors such as connection and mechanical device malfunction of the brought equipment and management factors such as safety inspections of equipment and surroundings before work are the most affected by the disaster impact. Accordingly, it is necessary to establish and implement measures through risk assessment during excavator work to identify industrial accident characteristics and social issues by industry and occupation to reduce accidents and deaths caused by industrial accidents, It is necessary to present policy directions and alternatives to prevent accidents and deaths more efficiently through multidimensional surveys and analysis of the risk of deaths and accidents in the area, and active research should be conducted.