AN ANALYSIS OF MENTAL WORKLOAD AT HIGH-ELEVATED WORKPLACES (1) - MEASUREMENT OF PSYCHOLOGICAL RESPONSES -
 
Usui, S., Osaka University and Egawa, Y., National Institute of Industrial Safety Independent Administrative Institution, Japan
 
The number of fatalities due to industrial accidents in Japan in 2000 was 1,889, with the construction industry accounting for the greatest share with 731. Furthermore, working at high-elevated places were one of the most dangerous jobs, with 301 of the deaths in the construction industry resulting from falls. The purpose of the present study was to make a psycho- physiological analysis in order to study the degree of mental workload on human beings at high-elevated places. Two experiments were carried out on scaffolding workers and office workers, who were made to walk along the footing boards of a temporary scaffold. In experiment 1, psycho- physiological responses of the subjects were measured. In experiment 2, the subjects?f spare capacity at an elevated place was measured using a dual task method. The results did not indicate any clear physiological response due to high elevation, although an increase in mental workload caused by the height was observed and secondary task performance fell at the high- elevated place in the office workers. The effect of the height was less noticeable on the scaffolding men than the office workers, but their spare capacity at that hight decreased as the task demand increased due to narrower footing boards or increased task difficulty.