Introduction. Knowledge the maximum size of the dcr particles actively involved in the combustion of dust/air mixture makes it possible to classify the dispersed materials selected in the production according to the explosion hazard without fire tests. For flammable polymers, in particular polyethylene, dcr ≈ (150 ± 50) microns (Hertzberg et al., 1982). If such a polymer contains a bulging component that multiplies the particle size when heated (hereinafter referred to as the bulging polymer), its explosion hazard must be assessed experimentally, paying special attention to the analysis of the validity of the conclusions obtained.

Features of the object of analysis. A bulging polymer is considered, the dust of which, according to the results of a standard study in an 18.7-liter chamber, was classified as explosive with a maximum explosion pressure of about 600 kPa. The doubt about the validity of this conclusion is due to the need to double the energy of the ignition source (up to 5 kJ) to initiate an explosion of the polymer air suspension.

Signs of explosion safety and discussion of the results. A thorough analysis of the results of the study of a bulging polymer revealed two features: the accidental occurrence of explosive air suspension in a wide range of dust concentrations and the presence of two inflection points in the ascending section of the pressure dependence in the blast chamber on time in single experiments. These features, in their main parameters, coincided with those found in anthracite and melamine, which exhibit explosive properties when tested in a 20-liter chamber, but are nonexplosive according to the results of large-scale tests in a 1 m3 chamber with an ignition source of 10 kJ.

Conclusions. The explosion hazard of the considered dust of a bulging polymer is unlikely under normal atmo­spheric conditions. The explosions in the 18.7-liter test chamber are caused by the initial heating of the air suspension by the heat of the burning ignition source and partial dust burning in the chamber. The final conclusion should be made based on large-scale tests.

Introduction. Experimental studies of the toxicity of the thermal decomposition products of the insulation of non-combustible electrical cables are relevant due to the lack of specific coefficients for the formation of toxic gases, which are necessary for fire-technical calculations.

Goals and objectives. The purpose of the paper is to obtain new experimental data on the specific coefficients of formation of an extended list of toxic gases that are formed during the thermal decomposition of the insulation of non-combustible cables. To achieve this goal, experiments were conducted in a small-scale experimental setup to determine the fire hazard of condensed materials in the case of thermal decomposition of the KVVGng(A)-LS 4 × 1.5 electric cable.

Methods. Measurement of the partial densities of toxic gases and oxygen, as well as the specific mass burn-out rate of cable specimens in a small-scale pilot plant. Processing of experimental data and analysis of the obtained results.

Results and discussion. It was found that during the thermal decomposition of the cable specimens under test, a mixture of toxic gases (carbon monoxide and dioxide, hydrogen chloride, hydrogen cyanide, phosgene, nitrogen dioxide, and acrolein) is formed, which is not taken into account in fire-technical calculations.
The dependence of the partial densities of oxygen and the above-mentioned toxic gases, the specific absorption coefficient of oxygen, and the specific formation coefficients of toxicants, as well as the specific mass rate of combustion of the specimens, on the test time was obtained.
To account for the scale factor (the difference in size between the small-scale experimental setup and the real room), the partial densities of toxic gases were plotted against the change in partial density of oxygen.
The analysis of the results showed that the partial densities of toxic gases exceeded or were comparable to their critical values for humans.

Сonclusion. The new experimental data on the specific coefficients of formation of the above-mentioned toxic gases can be used in the calculation of fire risks in rooms where non-combustible cables are used or manufactured.

Introduction. As part of the implementation of the Order of the Government of the Russian Federation dated August 29, 2025, No. 2366-r, there is an active development of gas-powered transport. In order to improve the level of fire safety at such facilities, it is proposed to use continuous monitoring systems for the gas-air environment.

Aims and Purposes. The purpose of the study is to conduct a comprehensive analysis of various regulatory documents in the field of fire safety applied to buildings with the presence of gas-cylinder automotive equipment, to process the obtained statistical data, and to supplement the method used in calculating fire risk to assess the frequency of fires at facilities for servicing vehicles using gas-powered fuel. To develop a method for improving fire safety, taking into account the possible placement of devices for detecting combustible gases at various facilities.

Research methods. To solve the set tasks, field tests were conducted at a specialized test site in Orenburg to study the concentration fields of combustible gas in an enclosed space. The data obtained were systematized and allowed for the development of proposals to improve the fire safety of facilities with GCE systems by monitoring the state of the gas-air environment.

Results and Discussion. Statistical data was analyzed to assess the frequency of fires. The calculation was based on the total number of vehicles in Russia, the proportion of cars with GCE systems, and the number of registered fire incidents. The results were systematized and studied in detail. Using the statistical data obtained and the proposed method for determining frequency, coefficients “a” and “b” were obtained.

Conclusion. Based on the data obtained, as well as taking into account the conducted analytics and experimental studies, a method has been proposed to improve the level of fire safety at service stations with GPT by taking into account the presence of gas analyzers at these facilities.
The proposed methodology, based on the possibility of accounting for devices for detecting gas contamination in various facilities with the presence of gas-cylinder equipment, will help reduce the likelihood of emergencies and improve existing calculation methods.

Introduction. The rationale is presented and a new direction in the field of organizational risk assessment is formed for the following reasons:

• organizational risks arise and manifest themselves under the managerial influence of the personnel of the management body on the personnel belonging to the category of production structural units, i.e. the nature of their occurrence is information that is characteristically described;
• organizational risks are currently being determined and eliminated independently in certain types of activities (industrial and fire safety, labour protection) that exercise control over the personnel of production structural units. Each type of activity is supervised by Rostechnadzor, the Ministry of Emergency Situations of Russia, and the Ministry of Labour, and reports on accidents, fires, and accidents at work do not contain information about the shortcomings of personnel in a particular area of safety in which such a risk arose and manifested itself in a dangerous event.

Purpose and objectives. The aim is to develop a model for assessing organizational risks in the integrated safety system at explosion and fire hazardous enterprises based on the orthogonality of the systems. A norm orthogonal model was developed to assess organizational risks in explosion and fire hazardous enterprises. Attention is focused on the reliability of the results obtained based on the construction of orthogonal systems, and an example is presented with the possibility of using the developed model in practice.

Methods. To solve the problems, the use of expert methods is justified, which will allow converting qualitative characteristics into a quantitative measure. The use of the prioritization method used in conjunction with the Gaussian probability distribution functional is substantiated. A model is proposed, displayed on an orthogonal plane by a directional vector, which represents the state of the integrated security system over the estimated period.

Conclusions. The rationale for the application of a group of expert methods and the method of directed vectors on an orthogonal plane is presented; their use makes it possible to obtain indicators of the impact of safety trends on the overall state of the integrated safety system of explosion- and fire-hazardous enterprises. An example is shown that makes it possible to prove the adequacy of using the model in practice for risk assessment.

Introduction. Product quality monitoring is an important task today, because it is impossible to guarantee the production of competitive products and to ensure a given level of safety. Nowadays there are no studies analyzing such a monitoring system or assessing its compliance, adequacy, and adaptability to specific production tasks.

Goals and objectives. The aim is to standardize the quality management methods monitoring system to improve the effectiveness of intelligent decision support in organizational systems. This can be achieved by integrating quality management methods and assessing the validity of the product quality monitoring system.

Methods. Analysis of the practical use of quality management methods, mathematical modelling of several quality management methods competing for the same management resources, and feasibility evaluation and examples of integration techniques to solve the problem of transferring information from one method to another.

Conclusions. Modern product quality monitoring systems have to meet the requirements of consistency, such as integrity, emergence, adaptability, accessibility, and other factors. Otherwise, the use of methods and specialized software would not improve product quality, ensure its competitiveness and compliance with safety requirements.

Introduction. In order to modernize the legislation in the field of fire safety, it is important to identify existing requirements that are outdated and/or redundant, in order to correct them. It is also important to expand the application of the existing mandatory classification system for various protected objects and substances and materials that can be a fire hazard. The most important areas of normative activity in the field of fire prevention are the development, modification, harmonization, and updating of mandatory and “voluntary” requirements based on the research of the regulatory framework governing fire protection requirements for industrial facilities, as well as the scientifically based selection of their application areas.

Goals and objectives. The purpose of this study is to improve the selection of the most effective and rational technical solutions for building a fire safety system for a protected object based on a broader use of the characteristics of the materials and substances used on the object, as measured by the specific mass rate of combustion. The objectives of the study include: justifying the need to clarify the initial characteristics of the materials and substances used on the protected object that affect the selection of elements in the fire safety system; justifying the use of the specific mass rate of combustion as a criterion for selecting rational technical solutions in the fire safety system; and proposing a sequence for developing a fire safety system based on the expanded consideration of the proposed criterion.

Аnalytical part. The practical examples substantiate the need for a more extensive use of the physical and chemical properties of combustible substances and materials that affect the choice of fire safety system elements. The expediency of using the specific mass rate of combustion for rational technical solutions in the fire safety system is shown. The sequence of developing a fire safety system based on the extended consideration of the proposed indicator is proposed.

Conclusions. Thus, the prerequisites for improving the existing mandatory fire-technical classification system are shown to establish objective fire safety requirements that take into account all the features of the protected object. The tools allowing the use of the criterion of the specific mass burnout rate are proposed. An approximate decision-making algorithm is described for choosing the most optimal elements of a fire safety system depending on the specific mass burnout rate.

Introduction. The necessity of analyzing international experience in ensuring fire safety in the use of lithium-ion batteries (LIB) was substantiated. The relevance of the paper is due to the large number of incidents involving fires and explosions at various facilities where LIB are used. The aim of the work is to provide an analytical review of research in the field of all possible aspects of fire safety in the use of LIB in different countries around the world.

Analysis of LIB accidents with fires and explosions. The accidents with fires and explosions taking place at LIB applications were analyzed. The three types of conditions leading to the LIB accidents were revealed: overheating or flame action; overcharge or short circuit; mechanical destruction.

Conditions of an initiation and evolution of LIB accidents. Main phenomena taking place at the LIB accidents were described. A thermal runaway with heating and decomposition of the electrolyte with a generation of high quantities of flammable gases occurs. An ignition of these gases may cause an explosion with the following fire. These gases can include hydrogen, carbon monoxide, methane, ethylene, propane and other hydrocarbons. A state of charge (SOC) of a battery influences strongly the consequences of the accident — the higher is SOC the more probable is the accident and the heavier are its consequences.

Methods for elimination of LIB accidents and fires. It was mentioned that an extinguishing of LIB fires is complicated by the circumstance that self-accelerating runaway reactions inside batteries proceed without a presence of oxygen. Therefore an application of gaseous, powder and aerosol fire extinguishing agents can lead to secondary ignitions after a liquidation of a flame if the necessary cooling of the battery is not made. A conclusion is made that water is more suitable and reliable agent for a fire extinguishing of LIB.

Conclusions. Based on the analysis, it was concluded that accidents and fires involving LIBs are caused by self-accelerating reactions in the battery electrolyte. In addition to heat release, this process generates a large amount of combustible gases. It was noted that water is recommended as a fire extinguishing agent.