Author/Authors :
Karami Masoumeh نويسنده , Zare Sajad نويسنده Department of Occupational Health, School of Public health, , Sahranavard Yaser نويسنده Health and Safety Executive Unit, Sarcheshmeh Copper Complex, Rafsanjan, Kerman, Iran. Sahranavard Yaser , Hakimi Hossein Ali نويسنده Occupational Health Expert, Sarcheshmeh Copper Complex of Kerman, Kerman, IR Iran , Hassanvand Davoud نويسنده Department of Occupational Health, School of Public Health, Kerman University of Medical Sciences, Kerman, IR Iran , Nabi Farokhi Mohammad نويسنده Department of Physics, Faculty of Energy Engineering and Physics, Amir Kabir University , Terman, IR Iran
Abstract :
[Background]One of the most common harmful factors in the workplace is noise. Noise control is a factor beneficial for health and safety in the workplace.[Objectives]The current study aimed to design and manufacture a silencer for the cooling tower pump of Sarcheshmeh Copper power station in order to control noise.[Methods]In this study, sound pressure level was measured by the use of a sound level meter (B & K 2260). Measurement was carried out in the light of ISO 1996 standard. After studying technical and acoustic features of the noise source, a dispersive-absorptive silencer was designed to control noise pollution generated by the cooling tower pump of the thermal station. After analyzing the frequencies of sound pressure level and using available data, a cylindrical silencer (with a diameter of 1.5 m and height of 3 m) was designed and manufactured. The internal part of the silencer was filled with different columns of absorbent material covered with punched metal. Therefore, the silencer consisted of (1) acoustic diffuser, (2) acoustic chamber, and (3) acoustic channels.[Results]Measurements showed that, at a distance of 1 m from the source, sound pressure level reduced from 127 dBA before installing the silencer to 79 dBA after the installation, resulting in a reduction of 48 dBA.[Conclusions]Using a silencer with absorbent material (glass wool) is very effective in reducing the noise generated by the pump.
