An engineering method was developed for determining the critical time of fire and determining the probability of evacuation of people from zone of fire, which makes it possible, with simplified dependencies, to quickly determine all the necessary factors in the evacuation process of people in case of fire in the building. To explain the use of the developed method, the sequence and example of determining the critical time of fire and determining the probability of evacuation of people from zone of fire for enterprise is considered. It was shown how one could calculate the time of evacuation of people from the premises from the zone of fire. The safety of people is provided when the time of evacuation does not exceed the time of the onset of the critical phase of the development of fire. For this purpose, the period for which the temperature, smoke density, oxygen concentration, hydrogen chloride, carbon dioxide and carbon monoxide gas reaches extremely dangerous values for a person was calculated. After determining all the necessary quantities, the probability of evacuation of people was analyzed in the absence of firefighting equipment in the building. The parameters determined by this new method are adequate and confirmed by other methods of calculation, in particular, developed by Hulida, Koval and FDS program. The relative error between the specified parameters does not exceed 8...12% (in comparison with other mentioned methods).
38 4) instant inclusion of smoke protection systems (smoke and heat removal system with opening mechanism) 5) automatic opening of evacuating doors; 6) instant inclusion of an automatic fire extinguishing system for objects.At the present stage, when installing fire protection systems (FPS) at the facility, a problem arises that they do not take into account for the facility, in order to reduce the cost of purchasing fire protection systems, the allowable service area for each device in the system. This approach leads to a decrease in the functionality of the fire protection system of the facility by 40...65 %. In turn, in case of fire at the facility, in this case, losses from the fire increase 2...3 times [1].Fire statistics indicate that the number of fires in warehouse buildings in Ukraine annually exceeds 130 [2]. In most cases, warehouses are burned to the ground for a large amount of fuel load and the failure of fire protection systems to ensure their fire safety. Over the course of 5 years, a significant number of fires occurred in the USA, namely 1210 in
Purpose. To develop a method for reducing the impact of fires in unsheltered timber warehouses on the environmental safety by reducing the duration of free burning of timber, the speed of fire front spread, emissions of combustion products and the duration of the firefighting. Methodology. During the experimental research, the method of fractional factor experiment was used. Theoretical research was performed using optimization mathematical models. The Monte Carlo method is used to solve optimization problems. To implement this method, block diagrams of algorithms was developed, based on written corresponded computer programs. Findings. The method was developed for reducing the impact of fires in unsheltered timber warehouses on the environmental safety by reducing the duration of free development of the fire, the speed of fire front spread, the concentration of combustion products and the duration of the fire. Fire prevention measures to reduce the duration of fire and to reduce emissions of combustion products due to fires in unsheltered timber warehouses was implemented by using an automated system to determine the fire extinguishing means and forces by setting an optimization problem, applying the Monte Carlo method and developing software to solve it. Originality. The scientific novelty is the justification of ways to reduce the duration of the free development of fire and to reduce the amount of toxic emissions using optimization mathematical models. Practical value. It is possible to use the obtained results in the practical activities of fire and rescue units of the SES of Ukraine and provide environmental safety in case of fire in unsheltered timber warehouse due to the practical implementation of administrative, legal and economic methods.
Introduction. Fires in closed premises of production and storage facilities are the most dangerous, because they hold large areas with a significant fire load. The current direction of providing a fire safety system at production and storage facilities in closed premises is to eliminate the conditions of the rapid development of fire and minimizing its effect through the use of fire curtains. This method of fire protection is practically not used in closed premises of production and storage facilities at the present stage. In most cases, fire partitions are used in such situations. Therefore, a topic issue today is the research of limiting the development of fires with the use of fire partitions and minimizing fire effects.Purpose. Investigate the process of spreading the fire in closed premises of production and storage facilities by using fire partitions to limit the speed of fire spread. Problem statement and solution. The following tasks must be solved to provide fire protection of production and storage facilities:1. to investigate the process of fire spread in closed premises of production and storage facilities without the use of fire partitions;2. to investigate the impact of fire partitions use on fire rate.Two possible modes of development fire in the premises are considered to solve the first problem: 1) with the presence of sufficient air (oxygen), with fire occurred in regulated fire load; 2) with insufficient air (oxygen), with fire occurred in regulated ventilation.It is necessary to choose the material and fire partition design accordingly to solve the second problem. The results of experimental studies [11] showed that fire partitions vermiculite-silicate plates can be used for various building structures manufacturing. Closed production and storage facilities structure analysis showed that these premises are constructed in most cases with a grid of columns 9Х12 m.Conclusions and proposals:1) There is only the first mode of fire with sufficient oxygen (air) in closed premises of production and storage facilities with a total area of more than 5000 m2 in the process of fire. The fire that occurred is regulated only by the fire load.2) The use of fire partitions between sections of the premises of production and storage facilities reduces the probability of fire spreading in the premises by about 3 times.3) It is necessary to continue research work in this direction to obtain more significant results of the process of development and spread of fire in the premises of production and storage facilities.
Formulation of the problem. Minimizing the consequences of fires is the problem of particular importance for the cities of Ukraine. Closed and open warehouses in industrial enterprises are the buildings of the highest risk. Due to the results of the analysis, the problem is that insufficient consideration is given to the provision of fire protection of industrial warehouse facilities. Proceeding from the above it is possible to state that the elaboration of the main directions of provision of fire protection of industrial warehouse facilities is very important. The goal of the work. To develop a methodology for providing fire protection of industrial warehouse facilities taking into account the fire risk. Tasks setting and their solution. To ensure the fire protection of industrial warehouse facilities, the following tasks must be addressed as a priority: 1) to develop a classification of industrial warehouse facilities for the possible grouping of fire-prevention means for protection of such facilities during fires; 2) to develop mathematical dependencies for determining the required number of fire-prevention means for industrial warehouse facilities; 3) to develop a methodology for providing fire protection of industrial warehouse facilities taking into account the fire risk. To solve the first problem, recommendations were taken into account, on the basis of which the scheme of classification of industrial warehouse facilities was developed. In order to solve the second task in the first stage, all necessary fire protection facilities were determined to ensure the fire safety of industrial warehouse facilities. After accepting all necessary fire-fighting equipment for the provision of fire safety of industrial warehouse facilities, mathematical dependencies have been developed to determine their required quantity. To solve the third task the recommendations of the World Health Organization and the Decree of the Cabinet of Ministers of Ukraine dated February 29, 2012, № 306 was used. Taking into account the above mentioned fire protection systems, mathematical models of fire risk calculation for closed, semi-closed and open industrial and warehouse facilities were developed. Conclusions and specific suggestions: 1. The mathematical models of fire risks for closed, semi-closed and open industrial warehouse facilities are given, which make it possible to develop a methodology for determining the optimal amount of fire-fighting equipment and thereby provide fire protection for these objects. 2. To optimize the choice of the required number of fire-fighting equipment, it is necessary to establish an optimization criterion that would be based on the determined direct losses from the fire, expenses of the fire and rescue units for the elimination of fire and expenses for fire protection. 3. The developed mathematical models of fire risks require further improvement with the aim of their introduction and use on the basis of information technologies. These models allow to take all necessary measures for providing fire safety during the audit of closed, semi-closed and open industrial warehouse facilities.
The results of the analysis of the technical and reference literature related to the technical fire extinguishing means showed that there is no complete data regarding the technical characteristics of the carriage trunks, which relate to the length of the continuous water jet depending on the fluid pressure, the diameter of the nozzle, the angle of its inclination and placement heights above the ground. The firefighting barrel trunks are mainly used for localization and extinguishing of open fires (for example, in open warehouses of timber, forest fires, etc.). In the process of eliminating such fires, it is necessary to control the flow of a continuous jet into the fire cell by changing the pressure, the diameter of the nozzle, the angle of the barrel and the like. Therefore, to solve this problem in terms of controlling the process of extinguishing a fire, the task is to conduct experimental studies and to obtain on the basis of the experimental results of an empirical mathematical model, which would take into account the influence on the length of the continuous jet of the above factors. According to the results of experimental studies, to obtain a mathematical model for determining the length of flow of a continuous stream of water by a flap barrel from the variables that influence the process of its control during the elimination of fire. To achieve this goal, it is necessary to solve the following tasks: 1) to carry out experimental studies to determine the length of the flow of continuous jet of water with a pallet barrel from the variables that affect the process of its management in the elimination of fire; 2) mathematically process the results of the experiment and obtain a mathematical model to determine the flow length of a continuous stream of water supplied by a carriage shaft; 3) to develop a methodology for controlling the process of choosing the length of a continuous stream of water, which is fed by a carriage barrel when extinguishing a fire. Experimental studies were conducted using a fractional experiment to solve the first problem. For experimental research used: 1) fire truck MAZ AC-4-60 (5309) -505M; 2) PLS-20P carriage barrel; 3) fire hoses for connecting the carriage barrel to the centrifugal pump of the fire tanker; 4) roulette at 5 m; 5) a goniometer for measuring and setting the angle of the barrel relative to the earth's surface; 6) barrel nozzles d = 25 mm and d = 32 mm. Based on the results of the experiment, a nonlinear mathematical model was developed to determine the flow length of a continuous stream of water supplied by a carriage shaft. The model developed also takes into account the effect on the length of the jet supply the height of placement of the carriage trunk above the ground. The mathematical model for determining the flow length of a continuous jet of water with a carriage trunk gave the opportunity to develop a method of controlling the flow length of a continuous jet of water. Conclusions and specific suggestions: The results of experimental studies to determine the length of the flow of continuous jet of water by a barrel trunk from variable factors made it possible to clarify the technical capabilities of carriage trunks and to develop a method of controlling the process of water supply in the event of fire elimination. A nonlinear mathematical model was developed to determine the flow length of a continuous jet of water by a carriage barrel, the adequacy of which was tested according to the Fisher criterion. To control the process of water supply, depending on the required distance to the fire, a step-by-step method is proposed to increase or decrease the length of the continuous flow of water by a flap barrel.
In order to reduce the number of emergencies and losses from their occurrence on the basis of forecasting, it is possible to develop and implement appropriate measures in advance that would prevent their occurrence. But at the present stage there is no such methodology that would allow forecasting of emergencies in cities, including fires. Therefore, to solve this problem, the task is to develop developed methodologies for predicting emergencies in cities, including fires. The goal of the work. Develop a methodology for determining the risk of emergencies in the city. In order to achieve this goal, the following tasks should be solved: 1) zoning the city area with consideration of potentially dangerous objects, high-risk objects and objects of strategic importance for the economy and security of the state; 2) to identify areas with appropriate degrees of risk of emergencies; 3) develop a methodology for determining the risk of emergencies; 4) to develop appropriate measures to eliminate possible emergencies at the facilities. To solve these problems, they used, as an example, a map of the location of objects of the Lviv Railway District. The total area of the district is 29.64 km2. The total area was divided into 25 squares, each 1.1856 km2. These squares include potentially dangerous objects, high risk objects, and objects that are of strategic importance for the economy and security of the state. Analyzing the risks of emergencies at the facilities in the railway districts of Lviv, it was found that these medium- and high-risk facilities occupy approximately 52% of the total area of the territory. A similar situation occurs in other areas of Lviv. The results of the analysis for other cities of Ukraine showed that, for example, for the cities of Dnipro and Mariupol, these risks for economic entities by city area are approximately 50… 65%. A methodology for determining the risk of emergencies at city facilities has been developed, based on the provisions of theories of probability and reliability for failure of elements of operation of city objects that can lead to emergencies, as well as appropriate measures to eliminate possible emergencies in the city. economic acts. Conclusions and specific suggestions: A methodology for determining the risks of emergencies at business entities has been developed, which makes it possible to perform the forecast of emergencies and to take appropriate measures to prevent them. To determine the risks of emergencies, we propose a method for establishing the law of distribution of failures of structural elements of an object that pose a threat to its occurrence. Such distribution laws include exponential, Weibull, Rayleigh and normal. The methodology developed needs to be further refined in order to implement and use it on the basis of information technologies, which will allow to take all necessary measures in an operational mode to ensure the elimination of possible emergencies in the facilities.
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