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Ïðîâåäåí àíàëèç ïîaeàðîâ íà îáúåêòàõ àòîìíîé ýíåðãåòèêè. Ñ ïîìîùüþ ðàñ÷åòíî-àíàëèòè÷åñêèõ èññëåäîâàíèé äèíàìèêè ïîaeàðîâ äëÿ òèïîâûõ ïîìåùåíèé ÀÝÑ îïðåäåëåíû êðèòè÷åñêèå âðåìåíà äîñòèaeåíèÿ îïàñíûìè ôàêòîðàìè ïîaeàðà êðèòè÷åñêèõ çíà÷åíèé äëÿ ëþäåé íà óðîâíå ðàáî÷åé çîíû. Äàí àíàëèç ïðèáûòèÿ ïîaeàðíûõ ïîäðàçäåëåíèé ïî îõðàíå ÀÝÑ íà òåððèòîðèþ ñòàíöèé ïðè ïîaeàðàõ. Ðàññìîòðåí ïåðå÷åíü ñðåäñòâ çàùèòû è òåõíè÷åñêîãî îñíàùåíèÿ îïåðàòèâíîãî ïåðñîíàëà ùèòîâ óïðàâëåíèÿ ÀÝÑ. Ðàçðàáîòàíû ìåðîïðèÿòèÿ ïî êîìïëåêñíîé çàùèòå îïåðàòèâíîãî ïåðñîíàëà ÀÝÑ, ïðîâîäÿùåãî ñïåöèàëüíûå ðàáîòû ïî âûðàáîòêå ýëåêòðè÷åñêîé ýíåðãèè ïðè ïîaeàðàõ â óñëîâèÿõ âîçäåéñòâèÿ îïàñíûõ ôàêòîðîâ. Ïðîâåäåíû êîìïëåêñíûå èñïûòàíèÿ òåõíè÷åñêèõ ñðåäñòâ äëÿ îáåñïå÷åíèÿ äåéñòâèé îïåðàòèâíîãî ïåðñîíàëà ïðè ïîaeàðå ñ èñïîëüçîâàíèåì ó÷åáíî-òðåíèðîâî÷íûõ êîìïëåêñîâ. Êëþ÷åâûå ñëîâà: ïîaeàð; àòîìíàÿ ýëåêòðîñòàíöèÿ; îïàñíûå ôàêòîðû ïîaeàðà; îïåðàòèâíûé ïåðñîíàë ÀÝÑ; íåïðèãîäíàÿ äëÿ äûõàíèÿ ñðåäà; ñðåäñòâà çàùèòû.

Introduction. Signal cables of safety systems, installed at nuclear power plants (NPPs), retain the ability to conduct modulated signals during the time period needed to switch the reactor facility to a safe mode. However, the ability of signal cables to transmit signals correctly in the high temperature gas medium, which is typical for the early stage of a room fi re, has not been exposed to research.Aims and objectives. The co-authors offer a theoretical assessment of the ability of NPP safety system cables to correctly transmit modulated electric signals if exposed to fi re and current loads. The theoretical research into the temperature of the conductor of a signal cable at the initial stage of fi re has been performed towards this end.Theoretical background. The steady state heat conduction equation, describing heat transmission from the cable core to the environment through the cylinder-shaped insulation layer, is used to measure the temperature of the cable strand.Results and discussion. Temperature dependences describing the relation between the temperature of the conductor of a single - strand and single-wire cable KNEPng(А)-HF on the gas medium temperature are obtained. Relations between the temperature of the gas medium in the room on fi re and the current intensity in the electric cable (if the cable is laid vertically) are presented with account taken of the dependence between the specifi c resistance of the wire and the temperature if the maximal permissible operating temperature of cable strands is 70 °С, the maximal permissible operating temperature of cable strands in the overload operation mode is 80 °С, and the maximal cable strand heating temperature is equal to 160 °С when the short-circuit failure occurs. Maximal current intensity values are obtained for various operating modes in the condition of temperatures typical for the initial stage of an indoor fire, they allow to correctly conduct modulated signals within the time period needed to switch the reactor facility to a safe mode.Conclusions. The developed mathematical model and results of numerical experiments allow to assess the infl uence of the temperature in the room of a nuclear power plant in case of fi re on the ability of a signal cable of the safety system to transfer undistorted modulated signals depending on current loads and signal cable laying patterns (whether it is laid vertically or horizontally), and also to expand the range of the room temperature dependence on the current load provided in Electrical Installations Code (EIC).

Currently, flame retardant materials made from polymers with flame retardant additives are widely used. However, the thermal effects of the fire on these materials from the point of view of the release of toxic gases are not sufficiently studied. The purpose of the article is an experimental assessment of the toxicity of the gaseous environment of a room during thermal decomposition of flame retardant signal cables used in the industrial premises and in the buildings with a massive presence of people. Experimental method is used for studying the process of formation of the hydrogen cyanide and carbon monoxide during thermal decomposition of the cable product samples in a small-scale pilot plant. The analysis of the obtained results was carried out. Density of the radiant heat flux incident on the cable surface, which is characteristic of a fire in a room, is modeled. Dependences are obtained concerning the partial densities of hydrogen cyanide and carbon monoxide, as well as the specific emission coefficients of these gases on the duration of experiments in the case of thermal decomposition of a modern flame retardant signal cable of the ng LS FR HF E1180 brand, the insulation of which is made of polymers with flame retardant additives. It is found that this cable under real fire conditions can release toxic compounds (carbon monoxide and hydrogen cyanide) in the concentrations exceeding their maximum allowable values during the evacuation of people from the premises. The obtained values of the specific mass coefficients of formation of CO and HCN, as well as the specific mass coefficient of O2 absorption, can be used in the mathematical models of the dynamics of fire hazards when calculating the time of blocking escape routes in the industrial premises, as well as in the buildings with a mass stay of people, where flame retardant signal cables are located.