an investigation of the effect of biorhythm on occupational accidents in the metal industry

background : biorhythm is one of the latest issues of subjective ergonomics. it can be effective in raising the level of job satisfaction, and therefore, preventing the occurrence of accidents in the workplace through understanding the physical, emotional, and mental characteristics of individuals. thus, the aim of this study was to examine the impact of biological cycles on occupational accidents in the metal industry. methods: this descriptive-analytical and cross-sectional study was conducted on 120 occupational accident cases in which individuals had caused the accident. finally, using data obtained from the accident reports and the easy biorhythm calculator, the relationship between biological cycles and occupational accidents was determined. findings: it was found that biological cycles affect the occurrence of occupational accidents. critical days and the negative physical cycle had greater effect on the occurrence of occupational accidents than mental and emotional cycles. conclusion: the findings showed that when individuals were in their critical days and the negative part of their physical cycle, the frequency of occurrence of accidents was higher. this was because the work was beyond the ability of the individual which resulted in the occurrence of an accident.