織布女子従業員の聴力障碍予防に関する研究

第1編 織布女子従業員の聴力について 第2編 織布女子従業員に対する耳栓(セレクトンK)の効果に関する研究 第3編 聴覚疲労に関する研究

抄録

A survey on the hearing impairment in a group of female loom attendants, investigations on the effectiveness of the use of ear plugs in prevention of such impairment, and auditory fatigue-test for the female workers were carried out and the following results were obtained.
1) Hearing impairments appeared in the female loom attendants in the third month of the work as dip-type high frequency hearing impairments with peaks in 4000cps-5000cps range. At the end of the sixth month the impairment reconered a little, but in one year it again tended to become worse in proportion to the number of working years. However, in all cases, hearing impairments in the speech frequency range were not observed.
2) Experiments on the insulation capacity of ear plugs were carried out. It was found that ear plugs attenuate noise in the high frequency range (over 2000cps) for about 30db. It was also found that loom attendants who wore ear plugs were almost completely free from hearing impair-ments at the end of one year. It was found, however, that further improvement in the appearance and material of the ear plugs was necessary.
3) Comparing hearing capacity of the workers before and after the 8 hours work it was found that the loom noise affected hearing particularly in 4000cps-5000cps range. Auditory fatigue-tests also showed many cases with prolonged recovery time after 8 hours work.
4) Although it was not possible to mark those workers who would be highly susceptible to hea-ring impairment at the time of employment only with auditory fatigue-test, it was found that those with remarkably prolonged recovery time were more liable.