The urgency of the issue to be considered is conditioned by the high fire hazard of electric cables of the voltage up to 1000 V. As a result of fires associated with this type of products at the industrial and storage units in 2020 in Russia, the volume of direct loss exceeded 68 % comparing to the fires caused by all other types of cable lines occurred at enterprises.
The high fire hazard of industrial facilities is mainly associated with numerous fire-hazardous premises containing combustible media capable of inflammation under the impact of ignition sources. In order to reduce their fire hazard, two independent and mutually reinforcing systems of fire-hazardous premise classification applied at designing such units are developed:
Identification of fire-hazardous zone’s class to ensure correct selection of electric equipment and level of its fire-protection.
Categorization of buildings and premises as fire-hazardous to ensure fire protection for both for buildings and attending employees. The main regulatory document where the requirements to fire-hazardous zone classification and selection of relevant fire-protected equipment were initially stipulated is the Rules for electric installations (1980). In 2008, the updated version of the Rules was incorporated into the text of the Federal Law of June 22, 2008 № 123-FZ «The technical regulation on fire safety requirements».
The studies conducted by the experts of The Federal State Budgetary Establishment «All-Russian Research Institute for Fire Protection of the Ministry of the Russian Federation for Civil Defence, Emergencies and Elimination of Consequences of Natural Disasters» of Russia serves as a basis to develop normative documents regulating categorization of fire-hazardous premises and classification of fire-hazardous zones as well as the recommendations on the scope of application of some electric equipment in fire-hazardous zones. The adopted classification of fire-hazardous zones is unique and has no analogues in global practices.
2. ISO 13943:2008. Fire safety. Vocabulary. Available at: https://www.iso.org/obp/ui/#iso:std:iso:13943:ed-2:v1:ru (accessed: June 16, 2021). (In Russ.).
3. Technical regulation on fire safety requirements: The Federal Law of June 22, 2008 № 123-FZ. Available at: https://docs.cntd.ru/document/902111644/ (accessed: June 16, 2021). (In Russ.).
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