The object of this study is the quantitative characteristics of magnetic fields induced during electric contact welding in various ways: contact point, arc-butt, capacitor point, contact-butt continuous, and pulsating fusion. The problem to be solved is the lack of necessary information regarding the electromagnetic safety of these welding techniques. A description of the proposed methodological approaches to determining the levels of magnetic fields, their measurement tools, and methods for assessing their impact on the welder's body is given. Based on the analysis and processing of the acquired oscillograms and spectrograms of magnetic fields, their quantitative characteristics were measured. To determine the general level of the polyfrequency magnetic field arising at contact welding, the proposed generalized indicator of the level of the magnetic field was used. It was established that during contact point welding by a stationary machine, the level of the magnetic field exceeds the maximum permissible value at the workplace in the range of 50–1000 Hz at a distance of 0.3 m from the welding electrodes. When manually welding in this way, the magnetic field level exceeds the permissible level in the frequency bands of 5–50, 50–1000 Hz directly near the electrical cable. Capacitor spot welding with direct current is characterized by exceeding the maximum permissible MP at the workplace in the high-frequency range of 1000–10000 Hz. During arc-butt welding, no excess of the maximum permissible levels of the magnetic field was detected at the workplace. It is shown that the spectral composition and magnitude of the magnetic field signal is determined by the welding technique and the initial parameters of power supplies. Orimani results can be used in the field of welding production and labor protection.

The results of investigations of chemical composition and emission rates of the welding fume, generated during welding using electrodes for copper alloys, are presented with the aim of improvement of their sanitary and hygienic characteristics. It is shown that in order to create new grades of welding electrodes with improved hygienic characteristics, it is necessary to have the data of the initial sanitary and hygienic evaluation in accordance with international standards. It was established that the use of binder based on pure lithium liquid glass in the coating of electrodes for welding copper alloys, increases the rate of welding fume emission into the air, as well as the content of manganese and copper oxides in it. The minimum rates of harmful emissions were recorded during the use of sodium-potassium binder, which is recommended for mass production of this type of electrodes.

This paper reports a study into the levels of magnetic fields induced by arc welding equipment in various ways in order to assess their impact on the body of welders. It is known that welders are exposed to a magnetic field of high intensity. Depending on the welding technique and the type of welding equipment, it may exceed the maximum permissible levels (MPL). Note that new Ukrainian sanitary standards for magnetic fields have been introduced, which regulate their levels depending on the frequency range. Therefore, it became necessary to carry out their hygienic assessment according to the new standards in order to devise appropriate methods for protecting welders. To this end, it was required to choose a new generation of devices to determine the intensity of magnetic fields induced by welding equipment. Based on the analysis of the constructed oscillograms and spectrograms of magnetic fields, it was found that semi-automatic welding with a metal electrode in carbon dioxide is characterized by an increased level of magnetic field in the frequency range of 50‒1000 Hz. With automatic arc welding under the flux, there are no excess of the maximum permissible levels of individual harmonics of the magnetic field but there is an excess of the total value of all harmonic components of the magnetic field. Manual arc welding with direct current involving a non-melting electrode in argon is characterized by a moderate level of magnetic field in workplace. During manual arc welding with coated electrodes, the exceeded level of the magnetic field is observed only on the electrode cable itself. It is shown that the spectral composition of the magnetic field signal is determined mainly by the welding technique itself, the peculiarities of arc combustion, and the nature of the transfer of electrode metal in the arc gap, as well as the initial parameters of the power supplies of the welding arc

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