Industrial noise and vibration leads to the workers disease, fatigue breakdown of pipeline and apparatus junction, decreasing of machine operating characteristics etc. According to statistics, amblyacousia and vibration illness takes the first places among all the other professional diseases. Investigations of noise and vibration levels at the operator's positions of "Volgoelectromontazh-1" Joint Stock Company of Russian Federation were done. Measurements were carried out according to existing methods and standards. In total 27 operator's positions were investigated in the main building and in the shop of consumer goods. The results of measurements showed, that for some positions (pendulum saw, cutting-off lathe, presses etc.) there were significant excesses of the sanitary standards of noise levels. Complex of measures of noise reduction was developed, including technical decisions and organizing measures. Results of measures implementation shows good efficiency of noise and vibration reduction.

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The calculation of noise generated by a jet of viscous compressible gas flowing out from a conical nozzle is considered. The calculations used the implicit version of the LES (Implicit LES, ILES), in which the role of the subgrid turbulence model performs numerical dissipation used finite-difference scheme. The distributions of the gas-dynamic and acoustic characteristics of the jet upon changing the conditions of its outflow are discussed. The analysis of the modal composition of the received noise is carried out and the correspondence between the features of the received directionality of the noise is determined by its various components and sources. The numerical simulation results are compared with the available experimental and calculated data.

The article considers two approaches to solving the problem of searching sources that make the greatest contribution to noise levels in the residential area caused by the enterprise engineering and technological equipment operation. The first approach is based on the analysis of the sound pressure levels in 1/3 octave frequency bands, the second one – of the levels of its narrow-band spectrum. It is determined that the results obtained using narrow-band analysis (Δf=1 Hz) provide more accurate results.

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