T. Shagdarova; A. Mukhіn; K. Kainazarov
In this article the peculiarities of investigation of the circumstances of an explosion of a gas-air mixture in apartments and housing construction are described, namely, an expert study of the place of the event as the main object of forensic expertise. Main traces of destruction characteristic of blast depending on the nature of the gas (natural, liquefied) used for household purposes are described.
The traces of destruction include: traces of the destruction of exterior walls, ceilings, interiors partitions, depending on the nature of the material (brickwork, wall panels).
It is noted that because of the shock wave in the explosion of gas-air mixture there is a collapse of the walls of apartments (houses) that are made of brick, while on the surface of the wall panels traces-destruction are characterized by the formation of cracks and large debris panel.
The article also gives examples of the calculation of the formation of an explosive concentration of the mixture, and the time of the formation of hydrocarbon gas at the gas leakage from the gas pipeline or the gas cylinder plant, taking into account the capacity of the pressure regulator: for the gas cylinder plant it was taken as 0.6 meter per second, for the main gas pipeline (in the apartment house) – 13.5 meter per second.
The calculation of the time of filling the room with gas from the gas cylinder plant or main gas pipeline to the formation of explosive concentration showed that when leakage from the gas pipeline formation of such concentration occurs much faster than when gas comes from the gas cylinder.
Particular attention is paid to the issues of expert investigation of criminal case materials and video reviews of the place of the event, provided form the investigator to the expert, reflection in the conclusion of the fact of the use of information contained in them as sources of evidence of the circumstances of the explosion. However, the main object, according to the authors, is exactly the place of the event, its material situation. Particular attention was paid to the importance of studying traces of destruction to the implementation of measures to eliminate the consequences of an explosion with the possible occurrence of a fire.
The article is based on the analysis of the practice of conducting forensic expertises in republican state utility enterprise “Center for Forensic Expertise of the Ministry of Justice of the Republic of Kazakhstan” where the possibilities of expert investigation of traces formed as a result of explosive (deflation) combustion gas-air mixture, taking into account the nature of their origin are shown.
Key words: explosion of gas-air mixture, explosive concentration of the mixture, gas equipment, emergency situations.