Evaluation for Fatigue and Accident Risk of Korean Commercial Bus Drivers.

Many Korean bus drivers work long hours, which causes fatigue and increased risk of accidents during driving. Their fatigue due to long working hours may cause a significant accident accompanied by injuries of the general population. The present study aimed to evaluate the fatigue and accident risk in Korean commercial bus drivers. The subjects were 16 city and express bus drivers with various work schedules: 2 shifts (2 shifts in a day), WR (duty-off), W2R (duty-duty-off), and W4R2 (duty-duty-duty-duty-off-off). We measured the subjects' heart rate in their workplace during their work and calculated relative heart rate (RHR) and maximum acceptable work time (MAWT), the maximum amount of time for which workers can sustain their workload without physical fatigue. Fatigue and risk index, which is a tool for assessing the risk from fatigue in the safety critical workers, was calculated using the subjects' work schedule. RHR ranged from 9.7 to 21.8% and MAWT was shorter than each subject's actual work hours. Fatigue (45.2-54.4) and risk indices (1.8) were high in WR schedule, which were higher than recommended value (30-35 for fatigue index and < 1.6 for risk index). According to these findings, Korean bus drivers worked long hours beyond their physical abilities, and the fatigue and risk indices were high, especially in WR schedule. It is necessary to prepare the policies to reduce the fatigue and accident risk in the Korean bus drivers including regulation for bus drivers' driving time restriction.