Introduction. The paper analyzes the changes in legislation that affect the algorithms for conducting control (supervisory) activities by inspectors of the Federal State Fire Supervision (hereinafter referred to as FSFS). The paper updates the list of operations performed by inspectors and conducts a survey of a representative selection of employees to assess the changes in labour costs associated with these operations. The paper also evaluates the impact of changes in labour costs on the performance of major operations and their individual components, taking into account the personal factors of employees. The obtained results were used to test the model of CSA distribution among employees of the Federal State Fire Supervision.

Goals and objectives. The purpose of the study is to test the applicability of the model of distribution of CSA between employees of the FSFS bodies, depending on their personal factors, which allows to optimize the overall structure of labour costs. The objectives of the study are to analyze changes in legislation in the field of organization and conduct of CSA, to develop their updated algorithms, to update data on labour costs for performing operations and their dependencies on the personal factors of inspectors.

Materials and methods. To solve this problem, we used traditional document analysis, decomposition, and statistical analysis (variance and correlation analysis).

Results and their discussion. In the course of the study, the algorithms of individual operations performed by the inspectors of the FSFS, as well as information on the labour costs for their implementation, were updated. Statistically significant differences in labour costs were identified between the inspectorate of different groups in terms of the length of service in the supervisory activities. The existence of a dependence of the performance of individual functions on the length of service of employees was confirmed. A mathematical model was developed to optimize the distribution of planned CSA in relation to the protection of various risk categories between the inspectorate, depending on the length of service of the inspector.

Conclusions. The proposed distribution allows for the optimization of labour costs for the large-scale operation “Inspection”, as well as for the practical transfer of experience between employees of supervisory activities. A comparative analysis of data obtained in 2021 based on similar studies was conducted. It was found that the proposed model for optimizing the distribution of CSA is universal and corresponds to the logical distribution of the number of inspectors by type of facility.

Introduction. The conducted research included an engineering calculation of the parameters of the smoke ventilation of the fitness club premises and the subsequent finite element modelling of smoke extraction processes using a software package. Comparing the results of the two methods makes it possible to evaluate both the accuracy of the engineering methods and the adequacy of the mathematical model.

Aim and objectives. The purpose of the study is to comprehensively assess the aerodynamic characteristics and effectiveness of the fire-fighting smoke ventilation system of a fitness club in a multifunctional building using a combined approach, including engineering calculation and finite element modelling. To achieve this goal, it is necessary to solve the following tasks:

• perform an engineering calculation of the mass flow rate of smoke and the available pressure for a natural system;
• to carry out a series of calculations in a software package for finite element modelling in order to determine the fields of aerodynamic parameters (speed, pressure) and visualize the fluxes of the smoke-air mixture for warm and cold periods of the year.

Methods. To solve the problems, the use of mathematical modelling of aerodynamic processes in smoke ventilation systems in buildings is justified to determine the parameters that determine the effectiveness of its operation.

Conclusions. The engineering calculation carried out and the subsequent finite element modelling of the operation of the smoke ventilation system in the fitness club of the multifunctional complex allowed us to obtain a detailed picture of the distribution of the main aerodynamic parameters in various operating modes and showed good consistency in key parameters: smoke consumption, velocities and pressures.

Introduction. Ensuring fire safety of Orthodox churches is a complex multi-purpose task that combines the issues of safety of evacuation of people in case of fires, preservation of cultural heritage, compliance with modern technical standards and taking into account the unique architectural and functional features of religious buildings.

The purpose of the work is to develop practical recommendations for the implementation of fire-resistant screen walls, which will ensure safe evacuation routes while maintaining the sacred aesthetics of temples.

Main part. The architectural features of Orthodox churches contribute to the rapid spread of smoke during a fire and complicate the evacuation of people. 
In Orthodox churches, the high fire load is due to the abundance of wooden walls and textile elements, which contributes to the rapid spread of fire and smoke, sharply reducing the time for evacuation.
The use of screen walls was proposed as a means of increasing evacuation safety. The key principle of designing screen walls for Orthodox churches is safe evacuation in case of fire and maintaining the visual integrity of the interior. 
The use of such walls will create conditions for the safe evacuation of people in case of fire, taking into account the development of evacuation models and architectural features.

Conclusions. Screen walls were proposed as a solution for safe evacuation in churches. The developed method of using screen walls for religious buildings using the example of Orthodox churches will create conditions for the safe evacuation of people in case of fire, taking into account developed scenarios and safety zones.

Introduction. It is well known that the particle size distribution of dust significantly influences its explosion hazard. The degree of coal dust’s contribution to an explosion depends on the reduction in the yield of volatile matter, which is dependent on the particle size distribution of the dust. This article examines the validity of an approach to determining the degree of coal dust’s contribution to an explosion based on the reduction in the yield of volatile matter between coal dust samples deposited in mine workings and a control crushed coal bed sample (fraction less than 200 µm).

Research Object and Test Equipment. The article presents a study of coal dust of grade “D”, grade “GZh”, grade “KO” based on technical and chemical analysis for a fraction of less than 20 microns, corresponding to the actual dust deposition in coal mines. A comparison is made with the results of technical and chemical analysis of grade “D”, grade “GZh”, and grade “KO” for fractions smaller than 200 µm.

Experimental results. The obtained results allow us to conclude that the yield of volatile matter from deposited mine dust (fraction less than 20 µm) and crushed formation samples (fraction less than 200 µm) remains constant within the error limits of the GOST 55660–2013 determination method.

Discussion of results. The limited time (7 min) of the volatile matter yield test results in the destruction of outer groups of coal macromolecules with low thermal stability, regardless of the particle size for fractions less than 200 µm.

Conclusions. The results of the study eliminate doubts about the validity of the approach used to determine the degree of coal dust involvement in explosions based on the decrease in the yield of volatile matter in a coal dust sample deposited in mine workings, compared to a control crushed coal bed sample (fraction less than 200 µm).

Introduction. The paper addresses the poorly structured problem of fire and rescue unit management in specific conditions — fire extinguishing in buildings with ventilated facade systems.

Purpose. Formation of control loops in fire and rescue units, taking into account the peculiarities of fire propagation in buildings with ventilated facade systems (VFS).

Tasks. Development of a classification of fire scenarios; determination of key control parameters; creation of an adaptive control system architecture; formalization of a fire extinguishing algorithm.

Theoretical foundations. A comprehensive approach that integrates methods of theoretical and empirical analysis to solve the poorly structured problem of managing fire and rescue units during firefighting in buildings with VFS. The object of research is the management processes during firefighting. The subject is the methods and algorithms for managing fire and rescue units. Methods: system analysis, mathematical modelling, statistical data processing, and control theory.

Analytical part. Analysis of fires in VFS, fire spread models (CFD, FDS), comparison of fire extinguishing agent delivery methods; three-dimensional classification by the nature of impacts (deterministic, stochastic, nonlinear), complexity of the fire-unit system, and level of awareness.

Results and discussion. Formalized initial data (quantitative and qualitative) for decision support by the firefighting commander/staff; classification of fire scenarios; key parameters; architecture of an adaptive system with deterministic-probabilistic models; firefighting algorithm as a basic sequence of combat operations with feedback. Novelty — formalization of processes based on three-dimensional classification.

Conclusion. Traditional methods require improvement for VFS; the expediency of adaptive network-centric models was proven. The methodology reduces the time of key decisions by 20–30 % (by modelling) due to the unification of scenarios and algorithms. Prospects is a software package for simulation modelling.

Introduction. The presence of a significant number of fire hazardous polymer play equipment and structures in children’s zones of public buildings determines the possibility for them to easily ignite and spread a fire. Regulatory requirements governing the fire safety of play equipment in public buildings are currently not formulated, which makes it difficult to assess their fire hazard level and choose effective ways to reduce it.

Aims and purposes. Investigation of the possibility of reducing the fire danger of children’s play zones to solve the problem of ensuring their fire safety by using modified fire-proof polymer materials or choosing fire extinguishing methods and means.

Analytical part. An analysis of the existing requirements of the regulatory and methodological framework for fire safety of play equipment of children’s play areas in public buildings was carried out, the results of a comparative experimental assessment of the properties of the fire load of various materials of game products were obtained. The influence of the use of flame retardants on the fire hazard indicators of polymer materials of play equipment was studied. 
The introduction of flame retardants reduces the flammability of polymer materials, however, the current sanitary and hygienic requirements for children’s play equipment limit their use. In addition, the presence of fire-retardant systems in polymer materials of products for children’s games does not reduce their smoke-forming ability and the amount of toxic gaseous combustion products, therefore, ensuring the required level of safety of people in children’s play and sports areas of public buildings by modifying the materials used cannot be achieved. 
The feasibility of using active fire safety methods for in children’s areas of public buildings using automatic fire extinguishing systems with finely dispersed water was considered.

Conclusions. To reduce fire hazard in children’s areas of public buildings, it is advisable to obtain objective information on the parameters of the combustible fire load of play equipment to calculate the dynamics of the development of fire hazards and assess the time of safe evacuation of people, as well as the choice of fire extinguishing means and methods.

Introduction. The introduction provides a brief analysis of laboratory methods for assessing the flammability of polymer materials. It is noted that there is virtually no data in the scientific and technical literature on the correlation of results obtained using small-scale methods for assessing the flammability of polymer composite materials (PCM).

Goals and objectives. The aim of this study is to establish a correlation between the results of small-scale methods for assessing the ignitability and flammability of PCM used in the Russian Federation. The research objectives include: obtaining specimens of PCM based on thermoplastic polymers and reactive oligomers, including gas-filled polymers; determining the flammability of PCM according to standard and laboratory methods; analyzing the results of small-scale methods for evaluating the flammability of the obtained polymer materials.

Materials and methods. The study objects included PCM based on PVC, syntheti.rubbers, and reactive oligomers containing various fillers, plasticizers, and flame retardants. The flammability of PCM was determined according to the current standards and methods described in the scientific literature.

Research results. A correlation was established between the oxygen index (OI) of the studied PCM and the results of other small-scale methods for evaluating the flammability of polymer materials.

Conclusions. It is shown that the OI of moderately flammable PCM should exceed 27 %, while for weakly flammable materials it should be over 31 %. It was revealed that the oxygen index method can be used in the development of next-generation PCM with reduced flammability and a specified set of operational characteristics.