Journal of Civil Protection

Research of changes in the dynamic hardness of gypsum boards under the influence of thermal effects of fire

Andrey V. Surikov — 2024-08-20

Purpose. To determine the change in the dynamic hardness of gypsum boards caused by exposure to high temperatures in order to establish the applicability of dynamic indentation of structures made from this material to assess the degree of thermal damage received in fire conditions.

Methods. Full-scale fire tests of gypsum boards. Dynamic indentation.

Findings. The possibility of assessing changes in the dynamic hardness of gypsum boards caused by exposure to elevated temperatures during a fire using the dynamic indentation method has been confirmed. Based on the fire tests of a frame-sheathing partition using a gypsum board of type H on a steel frame, the results of determining the change in the dynamic hardness of a gypsum board of the specified type are presented. In addition to the maximum temperature on the surface of the gypsum board, the heating time has a significant influence on the change in the indentation depth of the indenters. It was established that in different areas of the material surface at values of maximum (120–130 °C) and average (104–115 °C) temperatures and different heating times, the value of the indentation depth of the indenter differs by 1.5–2.0 times.

Application field of research. The obtained research results can be applied in the development a method for identifying the source of a fire based on the degree of thermal damage to structures made using gypsum boards.

Model for assessing the efficiency of fire extinguishing reservoirs of oil products

Andrey S. Perevalov — 2024-08-20

Purpose. Development of a model for assessing the efficiency of fire extinguishing of oil product storage tanks; substantiation of promising fire extinguishing methods for vertical steel tanks (hereinafter - VST).

Methods. Justification of promising methods of fire extinguishing in oil product storage tank farms was carried out by the method of hierarchy analysis.

Findings. The canonical efficiency indicator including resource intensity, reliability, safety and efficiency with their subsequent decomposition in hierarchical form is presented. The available subjective judgments of experts allow not only to identify one priority direction of improving the methods of fire extinguishing in VST, but also to determine the weight coefficients of efficiency indicators. Improvement of methods of creating an insulating layer over the combustion surface, as well as the development of new and promising techniques to stop combustion for different scenarios of emergency development in oil product storage tanks, is a priority direction to improve fire safety in case of fire in VST.

Application field of research. The results of the research allow not only identifying the priority direction of fire safety improvement in case of fire on VST, in particular, improving the methods of creating an insulating layer over the combustion surface, but also to model the efficiency index of automatic fire extinguishing installations of the tank farm.

Quantitative description of the mechanisms of formation of low multiplicity air-mechanical foam for firefighting needs

Andrey N. Kamlyuk — 2024-08-20

Purpose. To theoretically evaluate the influence of various factors on the generation of air-mechanical foam obtained in fire extinguishing devices. To compare the obtained data with the results of experimental studies.

Methods. Theoretical and empirical methods of analysis were used in the research process.

Findings. As a result of calculations, the data on the limiting (minimum and maximum) speeds for the liquid flow were obtained, in the range of which the generation of low-expansion air-mechanical foam is ensured for a wide class of foam-generating devices. The mechanisms of foam generation on grids in nozzles of fire trunks by the blowing method, on the surface of foam sprinkler rosettes of automatic fire extinguishing systems by the whipping method, and also by introducing air into the mixing chamber are considered.

Application field of research. The results of the analysis can be used in the development of foam-generating devices, as well as to determine the optimal modes of their operation.

Obtaining optimal parameters of high-speed electrochemical deposition of nickel coatings for parts of fire rescue equipment by the method of mathematical planning of the experiment

Olga V. Reva — 2024-08-20

Purpose. Development of a mathematical model of a multifactor process of hydrometallurgical synthesis of protective nickel coatings for fire rescue equipment parts from high-speed silicofluoride electrolytes to determine the optimal technological modes of operation when varying a number of factors (concentration of nickel silicofluoride in solution, cathodic current density, solution temperature).

Methods. The randomization method, standard techniques for determining electrochemical characteristics (thickness of deposited nickel coatings, current yield of the cathodic reaction), the «Desirability Profiles» module of the STATISTICA software package, as well as the method of full factorial experiment to obtain a regression model were applied in this work.

Findings. A full factorial experiment using a new high-speed silicofluoride electrolyte for nickel plating at three levels of factors affecting the deposition rate of nickel coatings was carried out: molar concentration of nickel silicofluoride (NiSiF₆) in solution c = 1; 1.25; 1.5 mol/dm³, temperature of electrolyte solution t = 40; 50; 60 °C, cathodic current density i = 8; 10; 12 A/dm². As a result of the analysis of experimental data, a regression model for predicting the deposition rate of nickel coatings in the studied ranges of changing of the varying factors was developed. Optimal values of the varied factors are: molar concentration of NiSiF6 in solution c = 1.2 mol/dm³; temperature of electrolyte solution t = 53 °C; cathodic current density i = 11.6 A/dm². Under these conditions, the highest value of the dependent variable (deposition rate of nickel coating), which is 240.7 μm/h, is achieved.

Application field of research. The developed regression model makes it possible to determine the optimal range for each of the main parameters of the system, in particular, the concentration of nickel silicon fluoride in solution, cathode current density, and electrolyte temperature, which makes it possible to outline ways to minimize side processes (formation of nickel oxo- and hydroxo compounds and hydrogen release at the cathode) to obtain protective nickel coatings with specified properties.

Improvement of the system of ensuring radiation safety of the border service of the Republic of Belarus

Evgeniy A. Il'yuchik — 2024-08-20

Purpose. Development and justification of the most promising areas for integrating artificial intelligence into the radiation safety system of border service agencies in order to increase its efficiency.

Methods. Analysis of the capabilities of artificial intelligence and extrapolation of the scope of its application into the radiation safety system of border services, modeling of the technical component of the system taking into account the integration of artificial intelligence.

Findings. The main factors determining the relevance of the use of artificial intelligence have been established, and the most promising directions for its application in the system for ensuring radiation safety of border service agencies have been proposed. An analysis of the technical means of radiation and dosimetric monitoring was carried out, which made it possible to develop the basic requirements for the elements of the system, taking into account the integration of artificial intelligence, including the basic design of data transmission and the possibility of introducing means of remote radiation monitoring and reconnaissance using a promising software and hardware complex for radiation monitoring and unmanned aerial vehicles. An elemental base of a software and hardware complex for radiation monitoring has been proposed, providing the possibility of introducing technologies for analyzing, assessing and forecasting the radiation situation within a section of the state border in the event of a radiological emergency, as well as choosing the optimal route for conducting aerial and ground radiation reconnaissance, taking into account the ability of artificial intelligence to remotely control unmanned aerial vehicle.

Application field of research. Ensuring radiation safety of border service of the Republic of Belarus.

Spreading of a drop of non-Newtonian viscous liquid over a solid horizontal surface

Valentin I. Baykov — 2024-08-20

Purpose. To investigate the kinetics of spreading a drop of a non-Newtonian viscous liquid over a horizontal surface.

Methods. Mathematical modeling.

Findings. The kinetic equation describing the process of spreading of a drop of non-Newtonian viscous liquid over a solid horizontal surface is obtained.

Application field of research. The obtained results are important for further investigation of the motion of non-Newtonian viscous liquids over a solid surface.

Particularities of the occurrence of large fires at oil and gas facilities and methods of reducing emergency CO2 emissions

Ekaterina A. Basova — 2024-08-20

Purpose. Research of theoretical and practical issues concerning the increased emission of carbon dioxide into the atmosphere as a result of large fires at economic facilities related to the handling of hydrocarbon fuels, as well as the development and testing of methods to reduce it.

Methods. The facts of large fires at the infrastructure of hazardous production facilities related to the handling of organic fuels, which became sources of significant atmospheric emissions of carbon dioxide, one of the most powerful greenhouse gases in terms of negative impact, were analyzed. The analysis of accidents that occurred in 2014-2023 in the Russian Federation at the facilities of pipeline transportation of organic fuels and tanks with oil and petroleum products was carried out. An innovative methodology for reducing the carbon footprint from large fires was proposed and presented with positive results of application experiments.

Findings. It has been established that the majority of accidents at the research facilities are associated with the occurrence of fires, as well as explosions of fuel-air mixtures accompanied by ignitions of combustibles. It is shown that many different causes, from those of technical nature to militarized terrorist attacks on oil and gas complex facilities, «break» the technological chains of fuel movement from production to consumption, causing accidental burning of gas, oil and oil products. It is proposed to consider the negative impact from emergency fires of organic fuels in terms of formation of a significant contribution to the emission of carbon dioxide as a dangerous factor of indirect delayed action fire. Application of the developed methodology leads to an increase in the total photosynthetic potential of plants and, accordingly, their absorption of carbon dioxide from the atmosphere.

Application field of research. Investigation of the processes of accidents, fires and explosions, development of ways to reduce hazardous effects on the environment, development of methodological foundations and regulations aimed at ensuring fire safety of defense objects.

Development of views on the use of civil defense forces

Vitaliy A. Khrokolov — 2024-08-20

Purpose. To analyze the development of opinions about the use of civil defense forces in wartime and the existing approaches to the justification of the composition of forces involved in rescue and other emergency operations as part of the civil defense groups.

Methods. General scientific methods of research: analysis and synthesis, comparison and generalization.

Findings. The main stages of development of opinions about the use of civil defense forces in wartime are determined.

Application field of research. The results of the work can be used in the training of specialists in the field of prevention and elimination of emergency situations as well as in the course of planning of individual measures of civil defense.

Children-parent relations and formation of children’s views about safety in the digital world

Viktor P. Sheinov — 2024-08-20

Purpose. To identify the relationship between parent-child relationships and the formation of children’s ideas about safety in the digital world.

Methods. Short version of the smartphone addiction questionnaire SAS-16 (by V.P. Sheinov), social network addiction questionnaire ZSS-15 (by V.P. Sheinov, A.S. Devitsyn), a questionnaire for studying child-parent relationships developed by the authors of the article, questionnaire of ideas about psychological safety by N.E. Kharlamenkova have been used. To obtain the results, quantitative and qualitative research methods were used. The basis of the empirical study were the results of testing of 1323 respondents.

Findings. It is shown that poor relationships between children and parents are associated with the development of addiction to smartphones and social networks, and this negatively affects the formation of ideas about safety in childhood. Children's smartphone addiction is linked to poor relationships with their fathers. For members of Generation Z, a positive relationship was found between smartphone addiction and how often they were scolded as children. It has been revealed that addiction to social networks is directly related to the poor relationship that women of all ages have with their mothers. For Generations X and Z, a negative relationship has been established between social media addiction and positive relationships with their fathers. Young people do not associate such concepts as “parents” and “relationships with parents” with the concept of safety.

Application field of research. The results of the study can be used by specialists involved in the development of a culture of life safety, as well as by teachers in explanatory work with parents on the prevention of addiction to smartphones and social networks and on the harmonization of parent-child relationships. This can be facilitated by holding family holidays and other events aimed at creating positive family relationships, as well as teaching children digital literacy.

Development of methods of ensuring fire safety of general ventilation systems

Vadim A. Kudryashov — 2024-08-20

Purpose. To conduct a retrospective analysis of fire safety design regulations for general ventilation systems, as well as fire resistance testing methods for ductwork; to determine the significance of the concept of fire resistance within the fire safety framework for general ventilation systems.

Methods. The retrospective analysis was conducted based on regulatory documents and standards published for the past 100 years. International and domestic fire resistance testing standards for general ventilation systems were compared.

Findings. Fires associated with general ventilation systems are quite rare events that carry serious potential consequences, and the level of these consequences cannot be classified as negligible. In most cases, measures to eliminate these consequences can be provided for and standardized, however, the rare nature of these events and the complexity of general ventilation systems led to a rather long and difficult period of formation of the fire safety regulation system in the field of ventilation systems. Fire resistance of general ventilation ductwork, along with the installation of fire dampers, is one of the key aspects of limiting the spread of fire outside the service area. The results of the research allowed the authors to prepare proposals for Amendment No. 3 to State Standards of the Republic of Belarus 11.03.01-2009 (May 2024), which provides for the possibility of conducting tests and criteria for assessing/extending the results to ventilation systems with an air duct side longer than 1600 mm. Refinement of the existing test method for air ducts made it possible to formulate rules for extrapolation (distribution) of test results for air ducts of a similar tested design with a side length from 1000 to 1600 mm.

Application field of research. The obtained results can be implemented in the system of fire safety regulation and standardization, in terms of concerning fire safety requirements for general ventilation systems, testing methods for ductwork for fire resistance and dissemination of test results.