中等度騒音下従業員の聴力自覚症と聴力検査成績との統計的観察（第2篇）

　I．緒言

　衆人熟知の如く，工場騒音の聴覚及び全身に及ぼす影響に就ては，幾多先人により種々の研究が発表されている所である。1958年松浦は，重騒音下従業員の聴力自覚症と聴力検査成績との統計的観察を行い，1959年望月は，某火力発電所，某製缶工場勤務者に於ける騒音性難聴調査成績を発表している。余は今回，上記研究に関連して，中等度騒音下従業員の聴力自覚症と聴力検査成績との相関性に就て統計的に観察し，稍々興味ある成績を得たので，茲にその大略を報告せんとするものである。

The effect of exposure to moderate degree of noise among factory employees is investi-gated in accordance to the formula 1/4(a+2b+ c) which was developed for this purpose. Observations covered: the effects on hearing and general health of each individual and nu-mbered the total of 548 ears.

The subjective loss of hearing and actual test results did not necessarily agree with each other; more often showed a marked dis-crepancy than not.

Eight percent of those who were thought to be normal showed a hearing loss by actual tests.

Tinnitus was found in 11.6% who were also affected by impairement of hearing

Sujective impairement of hearing was com-plained of by 53.1%; by test these individuals were found to be normal in hearing.

Also 40.2% complained of tinnitus and loss of hearing; by test results these were normal.

Hearing acuity showed a gradual reduction after the individual has reached or passed the age 41.