Hygiene Assessment of Noise Levels in Main Workplaces in the Plastics Industry

Abstract

Labour of workers of the main occupations of plastic products manufacturing is connected with complex influence of harmful factors, of which one of the leading ones is mechanical, inconstant, broadband noise with predominance of high and middle frequencies. At frequency of 500 Hz the high level was set at sawing operation 83,6±1,1 dB, at frequency of 1000 Hz - 80,8±0,37 dB, that on the average exceeds by 5 dB the normative value. Noise with predominance of high frequencies of 2000 and 4000 Hz was also determined during sawing in the chipper, respectively 83,6±0,68 and 86,4±0,93 dB, which exceeded the norm 73 and 71 dB taking into account the normative document. At frequency of 8000 Hz at MPL 69 dB the peak of sound pressure was revealed only at works, carried out near a crusher (88,2±0,37 dB), that is caused by poor-quality repair, unbalancing of separate units and mechanisms of machines, untimely lubrication and other reasons. In order to reduce the intensity of industrial noise its attenuation at the source of formation is of great importance: introduction of low-noise machines, timely repair of electric motors, constant provision of workers with personal protection means – “Earplugs”, timely passing of periodic medical examinations.