Fatigue Study Among 12-Hour and 7-Hour Night Shift Workers in the Manufacturing Industry

Abstract

In recent years physical and mental fatigue has received much attention due to its impact on work performance and its prevalence in night shift works. The aim of this study is to describe the self-reported fatigue of workers from 7-h and 12-h night shifts to investigate whether fatigue is related to night work schedules. The presence of fatigue was assessed with a multidimensional self-report instrument which includes the sociodemographic information of individuals, the Yoshitake’s fatigue symptom checklist and the Corlett-Bishop’s musculoskeletal disorder map. We found that fatigue was significantly more prevalent among workers of 12-h shift compared to fatigue in 7-h shift workers. Substantial differences in self-reported fatigue were found through the days and weeks among the workers of the two shifts, an exception was found for fatigue between lapses of 7-h shifts where fatigue tended to the same pattern for all lapses. Our results are consistent with other studies that establish strong links between perceived fatigue and work schedule. Upper body musculoskeletal disorders increased through the weeks as well as perceived fatigue. Further studies are needed for exploring the influence of other factors associated with fatigue on night shift workers, which include sleep deprivation and previous work.