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Purpose. Improving the process of managing occupational risk (OR) in occupational safety and health management systems, due to the distribution of dangerous factors which increase the probability of a dangerous event into several phases: before the occurrence of a dangerous event and after its occurrence. Methodology. The method of morphological analysis is used, which is based on the selection of possible solutions for individual parts of the task based on several morphological typical features important for the problem being solved, and the compilation of all possible combinations of hazardous factors and precautionary measures that will allow reducing the amount of occupational risk. Findings. A new approach to occupational risk management is proposed, which involves the division of all dangerous factors into several phases: before the occurrence of a dangerous event, after its occurrence, provision of pre-medical assistance, provision of emergency and medical care. Typical dangerous factors are defined that increase the probability of the occurrence of a dangerous event, which relate to the first phase (before the occurrence of a dangerous event), as well as dangerous factors that affect the severity of accidents and are characteristic of the second, third and fourth phases (after the occurrence of a dangerous event). A concept was developed for calculating the magnitude of occupational risks, based on the consequences of the occurrence of a dangerous event or by the type of injury with the area of responsibility of the enterprise; from the consequences of pre-medical care or the condition of an injured person with the area of responsibility of the enterprise and with the consequences of emergency and inpatient medical care or the state of loss of health of the employee with the area of responsibility of the medical institution. The hierarchy of preventive measures has been improved due to the addition of protective measures consisting of pre-medical care, emergency medical care, in-patient medical care. Originality. When assessing professional risks, it is proposed to determine the amount in accordance with the area of responsibility of the enterprise and and medical institution taking into account dangerous factors corresponding to a specific phase. Practical value. Examples of three matrices for assessing the occupational risk have been developed, taking into account the classification of the severity of the consequences for the health of the employee, which occurred immediately after the occurrence of a dangerous event (accident), after the provision of pre-medical care and after the provision of emergency and medical care. A description of preventive actions to reduce the severity of the consequences is proposed, taking into account the sphere of responsibility.

This paper reports a study into the structural-phase composition of the doping alloy made by processing metallurgical anthropogenic waste involving reduction smelting. This is required for determining the technological parameters that ensure an increase in the level of extraction of target elements during the processing of anthropogenic waste and for the further use of the doping alloy. It was revealed that the phase composition of the doping alloy manifested a solid solution of the doping elements and carbon in α-Fe. Cementite Fe3C and silicides Fe5Si3, FeSi, and FeSi2 were also identified. In this case, the doping elements were more likely to act as substitution atoms. It has been determined that the microstructure of the alloy consisted of several phases of different shapes and contents of the basic doping elements. Sites with an elevated iron level of up to 95.87 % by weight in the composition could be represented by the solid solution phase of the doping elements and carbon in α-Fe. The sites with a relatively high (% by weight) content of carbon (0.83‒2.17) and doping elements ‒ W, up to 39.41; Mo, up to 26.17; V, to 31.42; Cr, to 9.15 ‒ were apparently of a carbide nature. The sites with a silicon content of 0.43‒0.76 % by weight likely included silicide compounds. The alloy's characteristics make it possible to smelt steel grades without strict carbon restrictions, replacing some of the standard ferroalloys. Neither phases nor compounds with a relatively high propensity for sublimation were identified in the material produced. Therefore, there is no need to provide conditions to prevent evaporation and loss in the gas phase of the doping elements. That could increase the degree of extraction of the doping elements

This paper reports a study into the features of the structural-phase composition of products from the carbon-thermal reduction of scale of high-speed steels that yields an alloying additive. This is necessary to determine the technological parameters that reduce the loss of target elements in the process of obtaining and using resource-saving alloying material. The study indicates that when the degree of scale reduction changed from 28 % to 67 % and 81 %, an increase in the manifestation of a solid solution of carbon and alloying elements in the α-Fe lattice was observed. At the same time, the intensity of the diffraction maxima of FeO and Fe3O4 decreased. In the reduced products, the presence of Fe3C, FeW3C, Fe3W3C, and WC was traced. With an increase in the degree of scale reduction from 28 % to 67 %, the disordered (of "loose" appearance) microstructure was replaced with the formed particles of round and multifaceted shape with different content of alloying elements. At the reduction stage of 81 %, the microstructure had a finely fibrous structure. Based on the suite of studies, the most acceptable degree of reduction of scale of high-speed steel, followed by the use of the obtained material as an alloying additive, is 81 %. At the same time, ensuring the degree of recovery at the level of 67 % would also suffice. This is due to the fact that residual carbon in the form of carbides provides an increased reducing ability and degree of assimilation of alloying elements with the restoration of the residual oxide component in the liquid metal during doping. Spongy microstructure contributes to faster dissolution, in relation to the corresponding standard ferroalloys. This ensures a reduction in the total smelting time and, as a result, a decrease in the energy consumed

One of the promising methods to dispose of agricultural bio-based raw materials is to produce compost by aerobic fermentation in rotary chambers. High efficiency of the composting process is achieved when a proper temperature mode is maintained at each phase of the process. Changes in temperature are directly related to the effective transformation of organic substrates by microorganisms and are the reason for the low quality of produced compost in terms of its agrochemical and microbiological parameters. It was established that a high-temperature regime is achieved on the condition that the amount of heat released during the biodegradation of raw materials by microorganisms is greater than the heat loss associated with the substrate aeration and surface cooling. Therefore, the time during which the fermented mass remains warm depends entirely on the substrate's physical-chemical characteristics, the parameters of the equipment, and the modes of its operation. To describe the established conditions, based on the equation of thermal balance, a mathematical model has been built. The model relates the thermal costs necessary to maintain the optimal temperature regime of the process to the substrate's moisture content and specific active heat generation, as well as to such an important thermal physical parameter of the chamber as the coefficient of heat transfer of the wall material. A rotary chamber was manufactured to investigate the thermal mode of the bio-based raw materials composting process. It has been experimentally established that the chamber walls' heat transfer coefficient of 1.6 W/(m2·°C), a value of the substrate's specific active heat generation of 9.2 W/kg, and a moisture content of 58 % provide for the thermal needs for the process with the release of 140 MJ of excess heat. The reported study could be the basis for the modernized methodology of thermal calculations of the bio-based raw materials composting process in closed fermentation chambers