The article deals with issues aimed at updating and clarifying the methodological foundations for conducting expert research carried out during a forensic firetechnical examination of fires in dry heat saunas, based on the practical experience of forensic experts.
The processes and mechanisms of combustion and development of fires, as well as their dependence on volumetric design and technological solutions of the object of study – dry heat saunas are considered. The staging of the occurrence and development of fires is determined, which is justified by the processes of combustion in a closed volume with limited gas exchange (pyrolysis) and free gas exchange of a fire (kinetic and diffuse combustion).
The features of the application of general methods of research to establish the source of fire during fire-technical examinations are substantiated in order to ensure the reliability of the expert opinion. It has been established that the generally accepted methods for establishing the source of a fire during fire-technical examinations, in some cases, do not meet the practical aspects of researching fires in dry heat saunas and should take into account the peculiarities of the spread of fire hazards in saunas, which is due to special architectural and construction solutions.
It is noted that consideration of the mechanism of occurrence and development of a fire in the premises of dry heat saunas is a clarifying tool for generally accepted methods for establishing a fire source during fire-technical examinations. At the same time, the correctness of determining focal signs at this stage of the expert study should be carried out taking into account the mechanism of fire development, depending on the volumetric and structural solutions of the research object (sauna rooms), which will ensure high objectivity and reliability of the expert opinion.
Based on the generalization of the results of existing theoretical approaches and practical developments, the general methods for determining the source of a fire during fire-technical examinations of fire research in dry heat saunas are clarified.
Accordingly, the establishment of a fire source during fire-technical examinations in dry heat saunas using general methods for assessing the degree of damage to finishing materials and building structures should take into account the influence of volumetric design solutions of the object of study on the process and mechanism of ignition and spread of fire burning.
The necessity of using refined methods of expert research to establish the source of fire during fire-technical examinations of dry heat saunas to ensure the proper level of objectivity and reliability of expert opinions is proved.
Key words: fire-technical examination, oxygen-air, combustion, pyrolysis, fire source, sauna.