Abstract
On the precision solder work in a small-medium sized factory assembling small electronic parts, the characteristics of the work load and the influence of long-term working on workers were investigated through a field research and a simulation experiment.
1. The field research results:
(1) The tendency for the appearance of subsidiary behaviors (SB), and for the complaints of subjective feelings of fatigue (SFF) and the sites of physical fatigue symptoms (SPFS) were comparatively similar to the results of the simulation experiment. This suggested that the characteristics of work load in the solder workshop showed the work load pattern seen in monotonous work. In addition, the work load during working hours was rather heavy.
(2) The main task took 90%. The paced factors in the solder workshop were at extremely high levels.
(3) It was surmised from the magnitude of cumulative fatigue index and the complaints of SFF and SPFS before work that workers suffered from a chronic psychophysiological work load.
2. The simulation experiment results:
(1) The variations of CFF, SB, the heart rate and the complaints of SFF showed the work load pattern seen in monotonous work. Increasing the work load appeared to cause a lowering of the cerebral cortex activity level with the lapse of time.
(2) The complaints of SPFS were concentrated in the sites concerning the work characteristics and increased with the lapse of time. It is thought that the magnitude of the complaint rate is related to the duration of the period of work.
(3) The near-point accommodation showed a decrease in the ocular accommodation function response with the lapse of time.
Based on the results of these two investigations, work management from now on was discussed.
