Nowadays the characteristics of the serial pressure-relief panels used to limit the pressure of gas explosions in the room are calculated from the results obtained in the model experiments. These data are available in well-known publications such as NFPA 68 (USA), and a series of works by researchers from the Moscow State University of Economics and Management. The papers state that an increase in the specific mass of panels in a gas explosion in a room leads to an increase in the time of their discharge and an increase in the maximum pressure value. On this basis practical recommendations containing quantitative parameters are given. However, the validity of using the results of model experiments for real structures has not been confirmed. The purpose of our work is to evaluate the validity of using the results of model tests in calculations of characteristics of real structures. The assessment was based on the results of a search for a general relationship between the results of model and full-scale tests. The search for dependence was carried out among the published data obtained on the models, and the results of our full-scale tests. The results of full-scale tests were obtained during testing of serial panels in a cubic-shaped explosive chamber with a volume of 10 m³, with a discharge area of 2 m². A propane-air mixture was used, ignition was carried out at the center of the chamber. It was found that an increase in the specific gravity of the panel from 9 to 25 kg/m² leads to an increase in the explosion pressure in the room by a value between 0.5 and 3.5 kPa, in comparison with the pressure at which the area attachment collapse. The reset time of the panel also increases from 10 to 50 milliseconds. Our data are in good agreement with the known model data, but only at a qualitative level. The attempt to combine the data of model and full-scale tests by one dependence was unsuccessful because the known similarity criteria developed for the explosion process in this case proved to be ineffective. Two conclusions were drawn: § it is doubtful to use the results of model experiments in calculating the characteristics of real lightweight structures; § at this stage of research, the effectiveness of LCS can be assessed only by the results of its tests under conditions close to real.

Introduction. The analysis of large fires and accidents at nuclear power plants in Russia and the world testifies to the serious consequences for the population living in the surrounding areas, as well as the state in general. Fires are most often arise in the machine rooms, the reactor compartments, open distribution devices and of the deaerator stacks. The specificity of fires at nuclear power plants is that they can appear as the initial event for the development of the project, or serious accident, and subsequent events initiated by the accident. This study considers the impact of a fire hazards to the operating nuclear power plant personnel and methods of protection against them in the mode of shift work. Materials and methods. There are conducted settlement and analytical research of the dynamics of fires in typical premises, buildings and technological nuclear installations and the analysis of the reaction fire units on the protection of nuclear power plants to the place of a call (fire). Theory and calculation. The resulting critical indicators of impact of hazardous fire on human factors formed the basis for the development of a special set of protective equipment of operating personnel. The list of human means of protection includes: § human body means of protection from exposure to sparks, open flame (the protective cloak, protective mittens, protective footwear, protective helmet); § respiratory protection and eye (breathing apparatus with compressed air). Results. Carried out a series of experiments, using the educational and training complexes showed acceptable level of protection against fire hazards and convenience of use the special set of means of protection designed for operating personnel. Discussion. The degree of protection of workers from the effects of fire hazards during the work in the initial stage of the fire can be considered acceptable based on use of developed set of means of protection and an adequate level of preparation. Conclusions. The study of the dynamics of development of a fire at nuclear power plants revealed that the main fire hazards affecting the execution of work atomic power plant operational personnel is the loss of visibility. The staff is not provided protective equipment must immediately leave the premises. Operational staff provided a special set of protection means can perform the work in the initial stage of the fire, and as part of a special unit for the prevention of accident, subject to appropriate training. Operational staff secured by a special set of protection means can perform the work in the initial stage of the fire, and as part of a special unit for the prevention of accident, subject to adequate preparation.

At the moment the domestic regulatory base, unlike other countries, not fully considers ways of independent rescue of people at the fire before arrival of fire divisions with use of the special protected mechanical means of inland transport from high-rise buildings. Numerous researches in this respect, the conducted settlement justifications, but also, the decisions on use of the special protected mechanical means of inland transport realized abroad from high-rise buildings, prove need of the account and realization of this action and for domestic normative documents and standard legal acts in relation to high-rise buildings. At the same time it should be noted especially the fact that use of elevators for transportation of fire divisions for the organization of independent rescue or rescue by forces of firefighters of divisions, doesn’t cancel need of the device of ways of evacuation and the emergency exits meeting the requirements of technical regulations and the corresponding sets of rules at all. Realization of the principle of independent rescue of people at the fire allows to reduce time of carrying out evacuation of people and a wrecking by fire divisions that can be proved by the calculations which are carried out on the certified or approved different ways techniques. Lag of development of provisions of the Federal Law No. 123 and the standard legal acts of the Russian Federation regulating questions of ensuring fire safety of subjects to protection from the level of technical development and requirements of construction branch is available.

The use of sprayed water to extinguish fires in petroleum products is limited by the relatively low rate of vaporization due to the large average size of the droplets of the extinguishing agent. As methods to increase the efficiency of water-based fire, an electrophysical method for controlling the properties of substances at the interface is used, as well as a reagent modification - the deposition of nanomaterial with multilayered carbon nanotubes (MWCNT) into the liquid, and the use of gelling agents to stabilize the nanofluid. Raman spectroscopy revealed the presence in the nanomaterial, in addition to MWCNT, of a large number of by-products of nanotube synthesis. In the electrophysical action, characteristic peaks of nanostructures in water and hydrogel are observed, due to the predominant grouping of MWCNT in the near-surface layer of the liquid. With the help of atomic force microscopy, extended carbon nanostructures included in the composition of the extinguishing agent, as well as traces of amorphous carbon, were observed. In the course of the study, it was found that the increase in the rate of heating of the nanofluid is directly dependent on the concentration of the MWCNT nanomaterial and increases in comparison with distilled water (by 70 % - for the concentration of nanoparticles in water by 1.6 % by vol. and by 50 % - for the concentration of nanoparticles in the hydrogel 1.0 % by vol.), which can be explained by an increase in the thermal conductivity of the system due to a larger number of carbon nanotubes that are conductors of heat from the source of heating. The results obtained allow to select from the presented liquids containing the nanomaterial at a concentration of 1.0 % by vol. as the most effective for cooling the combustion of petroleum products of the combustion zone and to ensure its stability. When determining the surface tension coefficient of a nanofluid, water surface with a nanomaterial (DW + MWCNT 1.0 % by vol.) has a surface tension reduction of 20 %, for hydrogels (DW + Carbopol 0.2 % by mass) - by 58 %. When impact occurs electrophysical additional reduction of surface tension by 10 % preferably for all samples. A significant decrease in the value of the surface tension of the nanofluid, due to the introduction of MWCNT and the gelling component, leads to a decrease in the droplet size by more than 20 % in comparison with the base liquid while maintaining the parameters of the spraying of the extinguishing agent. This helps to reduce the size of droplets in the fire extinguishing substance in the near-surface layer of the burning liquid, increases the efficiency of the process of extinguishing the flame of petroleum products. During the experiments, it was found that the quenching time of water-based nanofluids with MWCNT nanomaterial 1.0 % by vol. on average 5.5 times less than the time of quenching the liquid with water. For hydrogels (DW + Carbopol 0.2 % by mass) with nanomaterial MWCNT 1 % by vol. the fire-fighting time was reduced to 10 times. The intensity of extinguishing water with nanomaterial MWCNT 1 % by vol. decreased by 2 times, and for hydrogels (DW + Carbopol 0.2 % by mass) with nanomaterial MWCNT 1 % by vol. - 3 times. In electrophysical conditions of exposure to the test is an additional nanofluids (10-15 %) reduction of the quenching time and the flow rate of the extinguishing agent. Summarizing the obtained results, it can be concluded that the increase in the fire-extinguishing efficiency of modified extinguishing agents based on atomized water is achieved due to the high thermal stability of the nanomaterial, improved thermal diffusivity of the nanoparticle with MWCNT, stabilization of nanoparticles in the liquid and reducing the rate of their agglomeration, reducing the droplet size by reducing the surface tension and increasing the fluid density.

This paper describes the results obtained during systematic experimental research of the oil product flame extinguishing process by injecting foam onto the burning surface and to the tank base. As a rule, the same foam generator, compound, chemical formula and proprietary component ratio are used for fire extinguishing using subsurface foam injection and and by feeding foam onto the burning surface. The only way to estimate the foam generator efficiency objectively is carrying out comprehensive testing during which curves are plotted for superficial and interfacial tension at the interface of water foam generator solutions with a hydrocarbon. Fluorated foam generators of known brands were used in the experiments: Ansulite AFFF, Shtamex AFFF, Light WaterFS 201, CAPSTONE 1183 and Shtorm-F. Hydrocarbon with different flash temperature was used as combustible liquids. As a result of the conducted experiments, a general regularity was discovered. It is the functional relation between the specific flow rate of foam generators and foam delivery rate shown using curves, the specific flow rate being minimum at the optimum delivery rate. The specific foam extinguishing efficiency characteristics have been determined during combustible liquid flame extinguishing. They are expressed as a complex of indices: critical and optimum delivery rate, and the minimum specific flow rate of the foam generator. The experiment results have shown that during oil product flame extinguishing using film-forming foam generator foam the value of the optimum delivery rate and minimum specific flow rate in case of subsurface foam injection was lower than during feeding of the foam onto the burning hydrocarbon surface by 25 to 30 %. Consequently, the extinguishing efficiency of the tested film-forming foam generators appeared to higher in case of the subsurface extinguishing method. The difference of indices of foam extinguishing efficiency in case of a particular feeding method is due to destructive effect of some contributing factors. While foam is only exposed to flame jet heat flow during the subsurface oil product flame extinguishing, in case of feeding from above foam is also destroyed as a result of the contact with burning oil product surface. Based on the obtained data, a model of the process of oil extinguishing by feeding foam to the tank base was developed. This model takes into consideration decrease of the burning surface temperature during mixing of homotermal layer when the foam emerges.

The purpose of this research is to design and experimental testing of a prototype system, which combines the use of a high pressure pump and reinforced hose to deliver suitable flow rates of liquid fire extinguishing agents (FEA) to firefighters in high-rise buildings at altitudes in excess of 200 m. The main components consist of a high pressure fire pump, coupled with 66 mm diameter reinforced high-strength delivery hoses. For altitudes up to 150 meters, it is permissible to use the traditional methods in which two centrifugal pumps connected in relay, the pressures achieved using relayed pumps in sync more than meet the needs of operations at this height. Issues are encountered, when it is necessary to push a column of water more than 150 meters, it is necessary to use alternative methods. To counter the issue, a holistic approach is required, encompassing a new strategy with modern equipment and methods of extinguishing fires at high altitudes. The new researched method tested combines the use of hoses of high strength with a working pressure of 3-4 MPa in conjunction with the high-pressure pump, for the purpose of the research, the chosen is a Rosenbauer NH25 with a parameters of 4 MPa at 6.6 l/s. The choice of high tensile strength hose is an important issue. As a result of calculations and comparative analysis of equipment, hoses of 66 mm diameter where determined as being the “Golden mean”. Another important element of the system is a specially designed adapter between the connections STORZ 38 and GOST R 53279-2009 66 mm “Bogdanovskaya”. In experimental exercises using an high rise with a height of 213 meters, a two-stage pump Rosenbauer N(H)25, and hoses of high strength Ziegler Pioneer 500 with a working pressure of 2.5 MPa, Æ66 mm was deployed and dry pipe Æ80 mm. It is also a very effective option if a dry pipe system can be intergrated into the method. There is no time for delivery of the vertical line and pic up of the FEA can be introduced on different floors. Theoretical estimates were confirmed in the conducted experiment, which proves the possibility of application. In comparison with existing methods, it as the obvious advantages of reduced time to deploy and much reduced manpower requirements. Analysis of working characteristics of the latter, samples high-pressure pumps Rosenbauer NH55, and the calculations, give the prerequisites for carrying out experimental exercises at altitudes of more than 350 meters to determine the maximum potential and development of recommendations for fire brigade use.