Statistical analysis of noise exposure levels for mine workers in Turkish Hard Coal Enterprise

Türkiye Taşkömürü kurumu ocaklarında gürültü etkilenim düzeylerinin istatistiksel analizi

Abstract

Development of modern mechanized operations in mining industry has been considerably decreasing the physical burden of work. But the most undesired and unavoidable by-product of these operations is the generation of high levels of noise. Occupational noise exposure of mine workers is a potentially serious health problem. High-level of noise not only hinders communication between workers, but, depending upon the level, quality, and exposure duration of the noise, it may also result in different type of physical, physiological and psychological effects on the workers, especially Noise Induced Hearing Loss (NIHL). Occupational exposure limits specify the maximum sound pressure levels and exposure times to which nearly all workers may be repeatedly exposed without adverse effect on their ability to hear and understand normal speech. The European Union has reached agreement on new directives dealing with noise in the working environment -Noise at. Work Directive 2003/10/EC. The Member States and candidate countries like Turkey are to comply with this Directive before 15 February 2006. The limit and action values are given in this directive. The specific objectives of this study were to estimate occupational noise exposure levels of mine workers employed in Turkish Hard Coal Enterprise and compare them with the exposure limit values.The method of Homogeneous Exposure Groups (HEG) was used for the estimation of occupational noise exposure levels of mine workers. The noise survey consisted of measuring and noting two variables: the noise levels to which the worker was exposed and his exposure time to those levels per work shift. After completion the survey, the daily noise exposure levels of groups were calculated. The homogeneity of the groups was tested statistically using one way analysis of variance. The normality of noise levels obtained for HEG's was investigated using Skewness and Kurtosis Coefficient of distributions and One Sample Kolmogorov - Simirnov Test were used to determine the normality of the data. In this study, the zonal method was selected as measuring technique due to the most cost-effective method. Noise measurements were carried out using a Type 1 integrated sound level meter (model NL-31) manu- factured by RION Co. Ltd., Japan. The equipment was operated on the A-weightedi network, slow response and was acoustically calibrated before, during, and after each shift. Calibration was done using the RION NC-74 sound level calibrator which emits a 94 dB, 1 kHz tone.It is necessary to define an average noise level characterizing the mean exposure of the person to check compliance of noise exposure with regulations or to estimate the individual risk of hearing loss of an exposed person. Two parameters are defined by the ISO 1999 (1990) standard. These are daily and weekly noise exposure levels. The daily noise exposure level (Licx.sh = Lao], ,8h - Lwj) is time weighted average of the noise exposure levels, in dBA, for a nominal eight-hour working day. It covers all noises present at work, including impulsive noise. This concept is used when the worker is exposed daily, for 5 days per week, to the same level.The daily noise exposure levels for underground workers varied from 73.9 to 103.3 dBA. The daily noise exposure level of face worker is 89.7 dBA. The daily noise exposure levels of workers employed in underground such as face, development sloping, transportation, eager, mechanization and press, drilling and pumping are out of compliance with the EU Noise Directive of 2003/10/EC. The calculated daily noise exposure levels for surface workers varied from 80.8 to 100.1 dBA. These noise levels were obtained for engineman and carpenter workers respectively. The daily noise exposure level of engine-man is only compliance with the EU Noise Directive of 2003/10/EC. The calculated daily noise exposure levels of other worker groups are out of compliance with the EU Noise Directive of2003/10/EC. The daily noise exposure levels for mining machine plant workers varied from 86.5 to 97.7 dBA. These noise levels were obtained for welding and mechanization and press workers respectively. The daily noise exposure level of machinist, casting and electrician were determined as 91.6 dBA, 97.6 dBA and 88.7 dBA respectively. The daily noise exposure levels calculated for all occupational groups are out of compliance with the EU Noise Directive of 2003/10/EC.

Özet

Günümüzde endüstriyel kalkınmanın ve modern teknolojinin ulaştığı düzey, bünyesinde birçok olumlu gelişme barındırmakla birlikte; yaşamı kolaylaştırmaya yönelik bu girişimlerin insan sağlığını olumsuz yönde etkileyen yanları da vardır. Bu tür olumsuzlukların biri de gürültüdür. Gelişen teknoloji ile birlikte gürültü, bütün işyerlerinde olduğu gibi maden işletmeleri için de önemli bir sorundur. Bu çalışmada, Zonguldak Taşkömürü Havzası 'ndaki ocaklarda çalışanların maruz kaldıkları gürültü seviyelerini tespit ederek, ulusal ve uluslararası standartlarla karşılaştırmak için uygun bir strateji geliştirmek amaçlanmıştır. Türkiye Taşkömürü Kurumu (TTK) 'na bağlı Yeraltı Maden İşletmelerinde işçilerin gürültü etkilenim düzeylerinin belirlenmesi için çalışanlar homojen etkilenim gruplarına ayrılmış ve gürültü ölçümleri herbir grubun gürültü etkilenim düzeyinin belirlenmesine yönelik olarak yapılmıştır. Homojenlik testi için tek yönlü varyans analizi kullanılmıştır. Normal dağılım varsayımının sağlanıp sağlanamadığının istatistiksel olarak araştırılmasında paramet-rik testlerderı Çarpıklık ve Basıklık Katsayıları ile non-parametrik testlerden Tek Örneklem Kolmogorov - Simirnov Testi kullanılmıştır. Yeraltı homojen etkilenim grupları arasında en küçük ve en büyük günlük gürültü etkilenim düzeyleri 73.9 dBA ve 103.3 dBA olarak sırasıyla Barutçu ve Sondaj işçisi için elde edilmiştir. Yerüstü homojen etkilenim grupları arasında en düşük ve en büyük günlük gürültü etkilenim düzeyleri 80.8 dBA ve 100.1 dBA olarak sırasıyla Kuyu Vinç ve Ağaç İşleri işçisi için elde edilmiştir. Maden Makinaları Fabrikası homojen etkilenim grupları arasında en düşük ve en büyük günlük gürültü etkilenim düzeyleri 86.5 dBA ve 97.7 dBA olarak sırasıyla Kaynak ve Mekanizasyon ve Pres işçisi için elde edilmiştir.