Suchergebnisse

A Thesis for applying for the degree of Doctor of Philosophy in Engineering Sciences. ; Väitekiri filosoofiadoktori kraadi taotlemiseks tehnikateaduste erialal ; Hearing loss is one of the most common health problems among military personnel. Active service members are mostly exposed to high-level noise from gunfire, blasts, and military vehicles commonly used by the Land, Naval and Air Forces. Prolonged exposure to noise increases the risk of noise-induced hearing loss (NIHL) and tinnitus. However, noise exposure can be reduced by using personal protective equipment or technologies with reduced noise levels. Noise levels were measured in vehicles and from weapons or weapon systems commonly used in the Estonian Defence Forces. The subjects of the study consisted of two groups: one group of subjects had to complete a questionnaire about their health and work-related risk factors. The second group had to first answer questions about their exposure to noise during their routine medical examinations. Subsequently, they underwent an audiometric examination in which testing was carried out at two frequencies. Based on the collected data, the associations between noise exposure, risk factors and NIHL were studied using various statistical methods. The data were also interpreted using mathematical equations and laws relevant to noise propagation and attenuation. Almost half of the active service members suffered from noise-induced hearing loss during their service period. The most important factors that could affect and facilitate prediction of the occurrence of hearing health problems in the military are the age of the active service member, service duration, shooting blanks, and driving vehicles such as PASI and Bandvagn. The most important finding was that military personnel who do not use hearing protection have more hearing problems than others who do. NIHL is difficult to prevent in the military during the active service period. Therefore, working out less noisy military technologies, vehicles, and weapon systems ...

CONTEXT: Hearing loss (HL) is a major health concern among military personnel due to noise from shooting, blasts, military vehicles, and noisy training environments. Nevertheless, one's exposure can be partially reduced by using personal protective equipment (PPE). The aim of this study is to estimate the prevalence of HL among military personnel, to analyse associations between HL and self-reported occupational and leisure noise exposure, and use of PPEs. MATERIALS AND METHODS: A cross-sectional study was conducted among 150 military personnel during their routine medical examinations. First, all participants filled in a questionnaire about their exposure to noise and later the respondents went through an audiometric test. The diagnostic criteria for slight, moderate, and severe HL was HL of 25–40, 41–60, and >60 dB at 4 and 6 kHz, respectively. The associations between noise exposure and HL were studied with multinomial logistic regression analysis. RESULTS: The prevalence of slight to severe HL in high frequencies (4 and 6 kHz) among study participants was 62.7%. Nevertheless, the majority of it was slight, as the prevalence of severe HL was 9.3%. The prevalence of any kind of HL was highest in the Navy and the prevalence of severe HL was highest in the Central Command Units. The relative risk ratios (RRRs) for HL were higher among those who had been working for a long time in a noisy environment, working with noise-producing equipment, driving in a PASI or a Bandvagn or had been shooting with blanks at least once per week. It also appeared that military personnel who had HL, reported tinnitus more often. Respondents' previous health problems, music-listening habits, and amount of exposure to loud noise in non-military environments were not independently associated with HL, but in several cases it increased the RRRs together with military exposure. We also found significantly more frequent HL among those never using PPEs. CONCLUSION: HL loss was more prevalent among personnel who are more often exposed to ...