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Документ Determining the dynamics of carbon monoxide formation during gas welding processes(Технологічний центр, 2021) Berezutskyi, Viacheslav; Khondak, Inna; Berezutska, NataliiaThis paper reports a study of the air medium where welding processes take place, with special attention paid to the evolution of carbon monoxide (CO) in the working medium in the process of gas welding. Plots were constructed and polynomial dependences were obtained to show a change in the concentration of carbon monoxide in the air of the working area during gas welding. It was confirmed experimentally that the concentration of carbon monoxide exceeds the permissible sanitary and hygienic indicators MPC (20 mg/m3) during gas welding. As a result of the experiment, the effectiveness of the use of an additional device was proven, namely an umbrella gas concentrator, in order to capture welding gases that are formed during gas welding. It was established that the MPC is exceeded under certain working conditions and welding wire. The carbon monoxide formation during gas welding was analyzed; these processes were compared with electric arc welding. The mathematical dependences derived make it possible to assess the risks of the welders’ work and conclude that the electric arc welding is characterized by a much higher rate of CO evolution from the beginning of the welding process (8.5 mg/s), that speed then decreases over 20 s by 2 times (to 4.5 mg/s). In 90 s, the speed becomes constant, to 2 mg/s. In comparison, gas welding has almost the same rate of CO formation, namely 0.3–0.9 mg/s. By changing the types of welding wires used in gas welding and taking into consideration the type of material that needs to be welded (including the period of its use), it is possible to influence the volume of CO emissions entering the working area and an employee’s respiratory area.Документ Assessment and prevention of the propagation of carbon monoxide over a working area at ARC welding(Технологический центр, 2019) Berezutskyi, Viacheslav; Hondak, Inna; Berezutska, Nataliia; Dmitrik, Vitaly; Gorbenko, Veronika; Makarenko, ViktoriiaThis paper reports a study of air environment at industrial premises where welding processes take place, with special attention paid to the formation of carbon monoxide (oxide) (CO) in the working environment in the process of manual arc welding. We have given the classification of basic harmful substances generated during welding and related processes in terms of the character of negative influence on the body of a welder. A mathematical model of the dynamics of change in the concentration of carbon monoxide in the air of a working area has been constructed, based on the amount of a harmful substance (m) in the air at premises at a time point, the intensity of its release into air, and the air exchange rate. A given mathematical model includes the propagation of carbon monoxide in the air, considering the air exchange between the overall volume of a premise and the local volumes of working zones. There are not enough studies into the formation of carbon monoxide during welding processes, which is why examining this process is a priority. Out experimental study has confirmed that the concentration of carbon monoxide outside the local volumes of local ventilation devices, that is in the air of working zones, remains constant (to 0.01 mg/m³) and does not exceed MPC (20 mg/m³). A failure or the absence of general ventilation leads to a rapid increase in the concentration of carbon monoxide (CO) in line with an exponential dependence (from 150 to 200 mg/m³ over 0.5-0.6 hours) within a small closed workspace (1 m³), and can quickly spread throughout the entire premise. However, a failure or the absence of general ventilation leads to a rapid increase in the concentration of carbon monoxide (CO) in line with an exponential dependence. This indicates that general ventilation is important, but it does not warrant safety for welders and other workers from gas poisoning. Therefore, the use of local ventilation must be ensured, as well as respiratory protection for all present when conducting welding processes. The derived mathematical models make it possible to assess risks during welders’ operations, to take into consideration CO emissions when calculating ventilation systems in working areas, to adjust the system that manages risks and labor safetyДокумент Studying the effect of multifunctional partitions on temperature indicators at offices of the open space type(Технологічний центр, 2018) Berezutskyi, Viacheslav; Berezutska, Nataliia; Ilinska, Olha; Raiko, ValentinaExisting partitions used in offices and at enterprises were considered, an analysis of use of partitions to ensure comfortable working conditions was performed and supplements to the classification system were systematized and introduced. Attention was drawn to the fact that the existing classification systems consider partitions based on the convenience of their use, material and design missing their influence on meteorological factors. As a rule, partitions are made from one or two layers of materials having different properties. They separate rooms or a working space at various heights from the floor. It was shown in the work that incorrectly arranged partitions made of expensive building materials can bring to naught the planned objectives of improvement of working conditions. In premises with high ceilings, conditions of irrational heating are likely to be created, both in the premises in general and concrete working zones. The studies have shown that this is solved by installation of partitions that direct and retain heat. It was found in the course of the study that temperature indicators in separated rooms are not significantly affected by the partition material type but the degree of room separation with partition by height is of paramount importance. As a result of temperature studies in premises of open space type where various partitions (glass pipes in a metal frame, ceramic panels, expanded polystyrene) were installed, it was established that partitions can significantly influence the temperature indicators but only if the room is completely separated in height. It was established that the material of partition does not affect the temperature indicators if separation is not complete (less than 100 %). The studies have proved the prospects of the scientific substantiation of the use of partitions and definition of connection between room separation and the factors affecting worker’s performance capability.