Sanitary and hygienic evaluation of working conditions and noise characteristics of equipment in the metalworking shop of the Tashkent passenger railcar construction and repair plant

Abstract

The article evaluates noise pressure levels at workplaces in the forging shop of the Tashkent Passenger Railcar Construction and Repair Plant in accordance with the requirements of GOST 12.1.050–86. Measurements were conducted using “Assistent” and “Octava–110A” noise meters, both certified and compliant with GOST 17187–81. The noise pressure levels emitted from the equipment were measured after identifying the background noise from adjacent shops. Background noise levels were recorded at three key points: the geometric center of the shop, opposite the open door of the adjacent mechanical shop, and 1 meter inside the entrance gate. Based on the collected data, tables, graphs, and diagrams were analyzed. The analysis revealed that the background noise from the mechanical shop exceeds sanitary norms by 1–12 dB in the 125–8000 Hz frequency range. At low frequencies, the noise pressure from the forging hammer was relatively evenly distributed, while at medium and high frequencies, it was predominantly directed toward the operator's position and the rear side of the equipment. Due to the rear side's proximity to a wall, sound waves reflected from the surface combined with direct noise, resulting in increased pressure levels. In such cases, to effectively reduce noise, it is recommended to use acoustic barriers and sound-absorbing screens. Placement of these elements should be based on the analysis of noise propagation directions, particularly in areas where high-frequency noise is concentrated—such as around the operator and near the rear wall of the equipment.