Journal of the Korean Society of Marine Environment & Safety (해양환경안전학회지)

The Korean Society of Marine Environment and safety (해양환경안전학회)
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Noise Exposure Level Measurements for Different Job Categories on Ships

선박의 담당업무에 따른 소음노출레벨 측정에 관한 연구

  • Im, Myeong-Hwan (Division of Onboard Training, Mokpo National Maritime University) ;
  • Choe, Sang-Bom (Division of Onboard Training, Mokpo National Maritime University)
  • 임명환 (목포해양대학교 승선실습과정부) ;
  • 최상범 (목포해양대학교 승선실습과정부)
  • Received : 2021.08.18
  • Accepted : 2021.10.28
  • Published : 2021.10.31
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Abstract

To minimize occupational noise induced hearing loss, it is recommended that workers should not be exposed to noise levels exceeding 85 dBA for over 8 h. In the present study, noise exposure levels were measured for seven workers based on their tasks on a training ship. The A-weighted noise exposure level (Lex,24h) was measured by taking into account the A-weighted equivalent continuous sound level (LAeq,i), duration (h) and noise contribution (Lex,24h,i) from the workers' locations. Results are thus obtained for different job categories as follows: officer group Lex,24h=56.1 dB, navigation crew Lex,24h=58.9 dB, navigation cadet Lex,24h=62.0 dB, ship's cook Lex,24h=64.3 dB, engine cadet Lex,24h=91.1 dB, engineer Lex,24h=91.1 dB, and engine crew Lex,24h=95.1 dB. It was determined that the engineers, engine crews, and engine cadets in charge of machinery must wear hearing protection devices. By wearing hearing protection devices when working in highly noisy engine rooms, it is estimated that the noise expose levels could be reduced by the following amounts: engineer Lex,24h=23.1 dB, engine Crew Lex,24h=24.4 dB, and engine cadet Lex,24h=21.5 dB. Moreover, if the no. 2 lecture room and mess room bottom plates in the cadets accommodations were improved to the 64 mm A-60-class floating plates, then further reductions are possible as follows: navigation cadet Lex,24h=4.3 dB and engine cadet Lex,24h=1.8 dB.

통상적으로 직업소음에 의한 청력손실을 최소화하기 위해서는 작업자가 8시간 동안 85 dBA 이상 소음에 노출되지 않도록 권고하고 있다. 이번 연구에서는 실습선박에서 7종류의 담당업무별 작업자들의 소음노출레벨을 측정하였다. 항해 중, 24시간 동안 작업자의 위치하는 A특성등가소음레벨(LAeq,i)과 소음장소의 지속기간(h) 및 소음기여도(Lex,24h,i)를 고려한 소음노출레벨(Lex,24h)을 측정하였다. 그 결과, 갑판사관 그룹 Lex,24h=56.1 dB, 갑판부원 그룹은 Lex,24h=58.9 dB, 실습항해사들은 Lex,24h=62.0 dB, 취사부원들은 Lex,24h=64.3 dB, 실습기관사그룹은 Lex,24h=91.1 dB, 기관사관 그룹은 Lex,24h=91.1 dB, 그리고 기관부원 그룹은 Lex,24h=95.1 dB를 나타내고 있다. 따라서 기관 업무를 담당하는 기관사들, 기관부원들 그리고 기관실습생들은 반드시 청력보호구를 착용해야함을 알 수 있었다. 소음이 심한 기관실에서 청력보호구를 착용한다면 기관사관그룹은 Lex,24h=23.1 dB, 기관부원그룹은 Lex,24h=24.4 dB 그리고 기관실습생들은 Lex,24h=21.5 dB의 소음노출레벨을 줄일 수 있을 것으로 추정된다. 또한 실습생들의 거주구역인 제2 강의실 겸 식당구역에 바닥시공을 64 mm, A-60-class 뜬바닥 구조로 개선했다면 실습항해사들의 소음노출도는 Lex,24h=4.3 dB, 실습기관사들은 Lex,24h=1.8 dB 정도 추가적인 감소가 있었을 것이다.

Keywords

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