直升機飛行員之職業性聽力損失

Occupational Hearing Loss among Helicopter Pilots

吳佳慧(Chia-Hui Wu) ； 辜志弘(Chih-Hung Ku) ； 劉紹正(Shao-Cheng Liu) ； 林曜祥(Yaoh-Shiang Lin)

《台灣耳鼻喉頭頸外科雜誌》 47卷2期 (2012/04) Pp. 137-145

https://doi.org/10.6286/2012.47.2.137

摘要

背景：相較於具有固定機翼的航空飛行器，直升機是一種需要靠一個或多個螺旋引擎來升降及推進的旋翼航空器。直昇機所帶來的噪音包括螺旋槳、引擎，以及傳動裝置噪音，長期暴露在直升機的噪音下可能造成飛行員的聽力損失。因此我們針對UH-1H直升機飛行員之噪音性聽力損失進行一項為期5年的研究。方法：我們針對UH-1H直升機飛行員使用縱向追溯研究方法來研究其聽力損失之情形。而所蒐集之數據來自於民國94年至民國98年飛行員年度健檢報告，其中分別包括了左、右耳在500 Hz、1000 Hz、2000 Hz、4000 Hz，以及8000 Hz頻率之聽力損失檢查。本項研究使用廣義估計方程式（generalized estimating equations, GEEs）來分析其相關性，另亦根據年齡差異做分析。結果：本研究對象人數自民國94年至98年，依序為166、130、136、141、及137員。各年度之聽力損失，無論左、右耳，皆以高頻率之4K Hz及8K Hz為最。經以廣義估計方程式分析結果顯示：就個人因素而言，連續5年來，通用直昇機機駕駛之聽力損失隨年齡而增加，年齡每增加一歲平均聽力損失0.35 dB，且達統計上之顯著差異。左耳之聽力損失平均大於右耳1.60 dB，已達統計上之顯著差異。就聽力損失之年度變化而言，95至97年依序與94年（95 vs. 94, 96 vs. 94, 97 vs. 94）之平均聽力損失差異並未達統計上之顯著意義；但98年與94年（98 vs. 94）之平均聽力損失差異達2.46 dB，且達統計上之顯著差異。在比較不同頻率之聽力損失，整體而言，1 K Hz vs. 0.5 K Hz與2 K Hz vs.0.5 K Hz之平均聽力損失並未達統計上之顯著差異；但4 K Hz vs. 0.5 K Hz與8 K Hz vs. 0.5 K Hz之平均聽力損失差異分別為6.17及7.40 dB，且皆達統計上之顯著差異。當同時考慮不同頻率之聽力損失（1 K Hz vs. 0.5 K Hz, 2 K Hz vs. 0.5 K Hz, 4 K Hz vs. 0.5 K Hz, 與8 K Hz vs. 0.5 K Hz），在年度之差異時（95vs. 94, 96 vs. 94, 97 vs. 94, 與98 vs. 94），8 K Hz vs. 0.5 K Hz在95, 97, 與98之聽力損失分別顯著高於94年2.45, 2.34, 及3.16 dB。結論：職業性「噪音性聽力損失」確實存在於通用直升機飛行員，在高頻處有逐年增加之情形。我們建議應加強評估飛行員的保護裝備，建立「預警移位」及「顯著閾值移位」之制度，並持續對飛行員進行職業衛生教育。

關鍵字

飛行員 ； 噪音性聽力損失

並列摘要

BACKGROUND: In contrast to fixed-wing aircraft, a helicopter is a type of rotorcraft in which lift and thrust are supplied by one or more engine driven rotors. The sources of helicopter noise include: rotor, engine, and transmission noise. Long-term exposure to the helicopter may result in pilots' hearing loss (HL). We report a 5-year study on the noise-induced hearing loss (NIHL) among the UH-1H helicopter pilots.METHODS: We conducted a retrospective longitudinal study (2005~2009) focusing on the hearing loss among the helicopter pilots. Data were collected from the pilots' annual physical examination records, including the hearing loss in left and right ears at frequency 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz and 8000 Hz. A generalized estimating equation was used to assess the association of hearing loss, as well as the adjustment with age.RESULTS: The numbers of study subjects from 2005 to 2009 were 166, 130, 136, 141, and 137, respectively. No matter which year or which ear, the most hearing loss were 4 K and 8 K Hz. The generalized estimating equation results indicated that the pilots' hearing loss increased with age, with hearing loss of 0.35 dB every year. On average, left ear learing loss was 1.6 dB higher than the righ ear loss. Compared to the 2005, the pilot's hearing loss of 2.46 dB is significantly higher in 2009. In addition, hearing loss at frequency in 4 K and 8 K were 6.17 dB and 7.40 dB, significantly higher than the loss in 0.5 K. Finally, analysis indicated that the association between different frequencies and hearing loss varied by time (different years). The variation (2006 vs. 2005, 2007 vs. 2005, 2008 vs. 2005, and 2009 vs. 2005) among frequency differences (1 K vs. 0.5 K, 2 K vs. 0.5 K, 4 K vs. 0.5 K, and 8 K vs. 0.5 K) were significantly higher in 2.45, 2.34, and 3.16 dB, respectively.CONCLUSION: It is evident that occupational NIHL may exist in the helicopter pilots. We suggest reevaluation of their hearing protective devices, such as ear plug, noise muffs, and helmet, establishment of regulation for early warning shift and significant threshold shift, and continuous occupational health education for the pilots.

並列關鍵字

pilot ； noise-induced hearing loss