The influence of the thermal load of the environment on electrical personnel using shielding personal protective equipment in open areas during the warm season

Introduction. The paper presents the results of a hygienic assessment of the intensity levels of electric and magnetic fields of industrial frequency and the functional state of the human body when using shielding personal protective equipment against electric fields of industrial frequency on open switchgears with a voltage of 220–750 kV in the warm season.

The study aims to explore the functional state of the human body using personal protective equipment against industrial frequency electric fields during work on open switchgears with a voltage of 220–750 kV, and the possibility of their regulation depending on the thermal load of the environment.

Materials and methods. The specialists measured the levels of electric and magnetic fields of industrial frequency in accordance with MUK 4.3.2491-09. Eight volunteers took part in the study to assess the functional state of the human body when using personal protective equipment against industrial frequency electric fields. Volunteers performed the work of electrical personnel for 60 minutes followed by a 30-minute recovery. We monitored environmental parameters based on measurements of the environmental heat load index and recorded indicators such as skin temperature and humidity, temperature and humidity under clothing, moisture loss.

Results. At the considered electric grid facilities, the researchers recorded the excess of remote adjustment of the electric field of industrial frequency up to 30 kV/m, in this regard, the use of personal protective equipment is mandatory. The obtained results of studies of the functional state of the human body revealed a tendency to increase the voltage of the mechanisms of thermoregulation of the human body using personal protective equipment against electric fields of industrial frequency when working on open switchgear.

Limitations. The number of volunteers was due to limited access to production facilities.

Conclusion. The regulation of work and rest modes of personnel when working in an open area during the warm season according to the index of the thermal load of the environment requires adjustment, since the studies have shown the need for stricter time regulation when operating personal protective equipment against an electric field of industrial frequency in a heating environment, taking into account their influence on the thermal and functional state of the human body.

Ethics. The study was approved by the Local Ethics Committee of the Izmerov Research Institute of Occupational Health (extract from the minutes of the meeting No. 3 dated 03/23/2022).

Contribution:
Perov S.Yu. — concept, design and organization of research;
Sazhina M.V. — collecting material and data processing, writing text;
Konshina T.A. — collecting material and data processing, writing text;
All co-authors — approval of the final version of the article, responsibility for the integrity of all parts of the article.

Funding. The study had no funding.

Conflict of interests. There is no conflict of interests.

Received: 14.01.2023 / Accepted: 01.02.2023 / Published: 25.02.2023

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