Influence of strict regulations on the use of hearing protectors in the Finnish Defence Forces.

The regulations concerning hearing protection during military training in the Finnish Defence Forces were renewed in 1989. The material of this prospective study concerns 912 consecutive conscripts (463 before and 449 after the new regulations) who were referred to the Central Military Hospital for acute acoustic trauma (AAT). We focused on three issues: (1) general habits regarding the use of hearing protection during shooting drills and combat training; (2) hearing protection at the moment of AAT; and (3) the cause of AAT. In combat training, the use of any hearing protectors was only 50% before the new regulations, but after they came into force the proportion was greater than 90%, and more effective protectors were used. However, at the time of AAT the hearing protection was absent in more than 80% of cases in both groups. The most common cause of AAT was small arms in both groups (83%).