Introduction. Intumescent coatings are used as a means of protection from heat flows, and their mission is to preserve the operability of wires and cables under fire conditions coupled with simultaneous current loading. However, the effect of insulation destruction on the operability of cables has not been studied for the case of a real fire regime.Goals and objectives. The purpose of the article is to evaluate the experimental operability of electrical wires and cables subjected to simultaneous effects of fire and current loadings.To achieve this purpose, an experimental testing unit was applied to conduct the experimental testing of wires and cables manufactured by various producers. At the same time, the temperature effect of the heated environment on electrical parameters of wires and cables, such as resistivity, inductance and capacitance, was evaluated.Theoretical background. In real fire conditions, dependence of indoor temperature, affecting the heating of cable insulation, differs essentially from the same dependencies in cases of various standard fire conditions. Therefore, the insulation destruction process may occur before the coating intumescence starts.Results and discussion. An experimental testing unit has been developed. This unit allows for the gradual cable heating with a pre-set temperature measurement interval and cable electrical characteristics. Dependencies of resistivity, inductance and capacitance of standard electrical cables on the temperature of the air surrounding the cable are obtained. It’s been discovered that the gradual heating of an electrical conductor or cable eventually leads to a short circuit between its conductive cores and further electric current transmission in electrical wires and cables. It is shown that phases and amplitudes of an input electrical signal can drastically change before the short circuit.Сonclusions. The simultaneous effect of fire and current loadings on standard electrical wires and cables causes a short circuit in the temperature range, in which no intumescence of flame retardant coatings is initiated on the insulation surface. Therefore, these coatings can ineffectively maintain the operability of electrical wires and cables.

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Introduction. One of the main problems of fire extinguishing at gas compressor stations is fires in confined spaces where electrical installations can be under voltage. To extinguish these fires, the co-authors propose to use jets of thermally activated water containing salts that inhibit burning. It is necessary to assess the electrical conductivity of water jets to prevent the exposure of fire-fighting units to electrical injuries.Materials and methods. In the experimental study, the principal electricity measuring instrument is digital dc megaohmmeter M4122U, which takes readings if operated from a laptop. The flow rate was measured using IT 2518 measurement complex and TDR14–2–3 primary flow converter of the turbine type. Termit T-35 hardness converter performed electromagnetic water treatment.Theoretical fundamentals. Measurements of leakage currents in jets of thermally activated water, fed through fire nozzles mounted onto a multi-purpose fire truck, were taken, and the maximum permissible distance to an electrical installation was determined experimentally and analytically using an experimental stand.Results and discussions. Averaged values of resistance of a jet of thermally activated water fed from a long-range nozzle at control points do not leave the confidence corridor with a probability of 0.95, which means that they do not cause a significant change in dc resistance. Inhibiting salt, injected into the water, reduces the resistance of jets of thermally activated water by no more than 2–3 % compared to under-heated water. The treatment of the inhibiting salt, injected into the under-heated water, using Termit T-35 hardness converter, does not significantly change the resistance of thermally activated water jets.Conclusions. It is theoretically and experimentally proved that the injection of inhibiting salts into the underheated water, as well as the electromagnetic treatment of water using low-power stiffness converters, do not significantly affect the electrical conductivity of jets of thermally activated water if compared to jets that contain no inhibiting admixtures. The extinguishing of surfaces of electrical installations using jets of thermally activated water containing flame inhibiting injections of salts, as well as the development of an inerting concentration in confined spaces of gas compressor stations is electrically safe for any person engaged in fire extinguishing.

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Introduction. The article considers the experience of application and aspects of improving temperature activated water technology for extinguishing fires as well as preventing and eliminating accidents. The technology for generating temperature activated water is described. The areas of the technology application have been explored. The advantages, disadvantages and some aspects of the technology improvement are presented. The purpose of the study is increasing efficiency of fire extinguishing and emergency prevention via using temperature activated water technology. Development of new technical means for supplying temperature activated water and fire extinguishing agents based on it. Research methods. To obtain the results, general scientific methods of cognition were used – analysis, synthesis, the theory of water boiling and hydro-gas dynamics. Reliability of the results presented in the given work is confirmed by application of the fundamental laws of physics and the proper mathematical tools. The results of the study. The advantages, disadvantages and some aspects of technology improvement are presented. It was explored that temperature activated water in a suspended state is able to dilute and cool the combustible medium and displace the oxygen of the air in enclosures, thereby eliminating the fire. The supply of hot water through hose lines over long distances (no more than 2 km) without loss of quality properties makes it possible to use the technology when extinguishing fires in hard-to-reach places. Low water consumption for extinguishing fires (up to 40 minutes without refueling) has a positive effect on extinguishing fires under conditions of limited water supply. The results of scientific research have been introduced into new models of appliances capable of performing a huge range of tasks set by EMERCOM of Russia. Conclusion. The information presented in the given publication will help managers and users of the technical means based on the temperature-activated water technology to apply and use it correctly for extinguishing fires and eliminating emergencies. The article discusses new aspects of the application, which allow us to suggest the possibility of extinguish fires, preventing and eliminating accidents in underground mine workings, subsurface suppression of municipal solid waste landfills, and extinguishing live electrical installations with temperature-activated water. The main directions for improving the technology are development and creation of new technical means for generating and supplying temperature-activated water and fire extinguishing agents based on it, as well as the study of its application at various protection facilities, including those located in the Arctic zone of the Russian Federation. Keywords: temperature activated water, explosive water boiling, fire extinguishing agent, fire extinguishing, fire appliances, multi-purpose fire appliance, multi-functional spray installation, set of multi-purpose fire containers.