Automatic Fire Extinguishing Systems Research Articles

Preparation and thermal responsiveness of microencapsulated fluorinated liquids for automatic fire extinguishing

Most early-stage fires originating in small confined spaces may not be effectively mitigated by automatic fire-extinguishing systems. Leveraging the unique controlled release capability and barrier properties of microcapsules presents a promising avenue for developing multifunctional and intelligent fire-extinguishing agents tailored for early-stage fire suppression. This paper introduces two types of microcapsules that integrate automatic detection and fire extinguishing functions, utilizing fluorinated liquids specifically perfluoro(2-methyl-3-pentanone) and 1,1,1,2,2,3,4,5,5,5 decafluoro-3-methoxy-4(trifluoromethyl)-pentane as core materials. The preparation process was optimized, and the thermal response of the microcapsules was evaluated by directly incorporating them into combustible materials. The results indicated a correlation between the preparation method, coating efficiency, and thermal stability of microcapsules with the core-wall materials. When the fluoride solution in the core material reaches the thermal response threshold temperature, the gas pressure generated during vaporization and phase change can break through the shell, enabling early active fire protection. Beyond a specific threshold of additive microcapsules in the material, the material exhibits self-extinguishing potential during combustion. In cases where the additive amount falls short of achieving self-extinguishing, the fire-resistant performance of materials can be enhanced through various measures. For instance, reducing the amount of fire-extinguishing agents, delaying the ignition time of fuel, and lowering the heat release rate during combustion are effective strategies. Moreover, the degree of improvement is related to the additional amount and the type of core-wall materials. The thermal-response mechanism of microcapsules constitutes a comprehensive mechanism with physical and chemical effects. The finding of this research offer a new technical approach for microencapsulating high-boiling-point gas extinguishing agents, facilitating intelligent and precise prevention of early fires resulting from combustible materials.

Fire risk assessment of Kashan's commercial and shopping centers using fire risk assessment method for engineering (FRAME)

AbstractCommercial buildings are considered as high‐risk units in fire due to the existence of expensive equipment and large presence of people with different ages. Therefore, the present study aimed to assess the fire risk of commercial and shopping centers in Kashan using the fire risk assessment method for engineering (FRAME). This cross‐sectional study was conducted using FRAME in 15 commercial and shopping centers in Kashan, Iran. The risk assessment data and FRAME checklist were collected by observation and interviews. Data analysis was conducted using Excel and Geographic Information System (GIS) software. The results of 46 checklists showed that the mean score of fire risk R for property was equal to 3.12, for people 3.81 and for activities 1.86. Also, the lowest risk for the property, people and activities belongs to Golestan Center with a score of 1.40, Valiasr with a score of 1.25 and Ataee with a score of 1.15, and the highest risk for the property, people and activities belongs to Mir Seyfi Center with a score of 5.80, Shafagh with a score of 9.96 and Sabz was 2.62, respectively. The present study showed the lack of proper ventilation system, lack of emergency exits, and lack of automatic fire alarm and extinguishing system were the factors affecting fire risk. Therefore, in order to prevent disasters and uncontrollable critical conditions, it is necessary to review the equipment of these buildings and to design and implement fire detection and alarm equipment and different ways of fire control in these centers.

Инженерный метод расчёта площадей пожарных отсеков в общественных зданиях

Purpose. The analysis of domestic and foreign regulatory documents showed that the regulatory requirements for the areas of fire compartments cannot be considered as scientifically based. It is necessary to develop a new approach to substantiate quantitatively the sizes of fire compartments. Methods. When making calculations, the area of fire compartments must meet certain criteria. An economic approach to calculating the size of fire compartments with the criterion of incurred costs is proposed. The areas of fire compartments must meet the conditions for fulfilling the optimization criterion, which takes into account the costs of creating fire protection for the building and the risk of material losses in case of a fire. Findings. The authors have presented analytical expressions of criteria to make a decision on the economic feasibility of using an automatic fire extinguishing system or fire walls, based on the criterion of incurred costs for one-story public buildings. The resulting formulas determine the critical areas of fire compartments; if these values are exceeded, it is advisable to use automatic fire extinguishing systems or divide the building into two fire compartments. Three options to determine the size of fire compartments for a one-story building have been considered. Research application field. The results can be applied in the context of alternative design of fire compartment areas when developing fire protection for specific facilities in compliance with the principle of economic feasibility. The formulas are simple and suitable for engineering calculations. Conclusions. It is proposed for facilities where fires can cause significant material losses, including social components of fire risks, to use the economic approach to determining the area of fire compartments based on optimizing the criterion of incurred costs. When comparing options for fire protection of a facility, the option that provides the minimum value of the criterion should be chosen. For three protection options: without fire walls and automatic fire extinguishing systems, with the use of automatic fire extinguishing systems or using fire walls, analytical expressions for the areas of fire compartments have been found.

New technologies for the creation of an automatic security and fire alarm system

The object of this study is the analysis of the latest domestic and foreign technologies for the creation of automatic fire alarm systems. The subject of the study is the fire protection system of the laboratory building of the University. The purpose of the study is to design a demonstration stand for an automatic fire alarm and fire extinguishing system in the laboratory building of the University based on the analysis of the latest domestic and foreign research. The theoretical and methodological basis for the analysis of Russian and foreign technologies in fire alarm systems were legislative acts, regulatory documents, and other sources on the topic of the work. A study has been carried out on the development of a demonstration stand of an automatic fire alarm system in modern conditions using statistical data and scientific publications of recent years. In the work, the structural and schematic diagrams of the stand for demonstrating the operation of automatic fire alarm systems are designed, the rationale for choosing the base of the main elements of the alarm system is given, the characteristics of the elements and their reliability indicators are calculated.

Automatic fire extinguishing system of the engine compartment of the car

The article discusses the statistics of vehicle ignition, the existing number of fire safety devices, their advantages and disadvantages. A technical solution is proposed based on the use of a dispersant sprayer, which allows mixing various chemicals into a ready-made fire extinguishing mixture, ejecting and spraying within a single process on the ignition source that has arisen in the engine compartment of the car. Keywords car safety, vehicle fires, engine compartment, statistics of car fires, fire extinguishing devices, dispersant sprayer, new technical solution

Experimental Quantification of Fire Damage Inside Pyrotechnic Stores

A fire inside a pyrotechnic store can lead to simultaneous initiation of the stored articles, regardless of their risk category, producing a shockwave caused by the released gas pressure. In fact, several accidents have occurred throughout history in pyrotechnic stores. This indicates the high risk posed by pyrotechnics due to their flammability. Due to the lack of global or European legislation on guidelines for the design of pyrotechnic stores and associated risk assessment, the present research aims to analyze the consequences of a fire inside pyrotechnic stores and to establish globally possible effective prevention and protection measures in order to reduce explosion risk and avoid future accidents. The observed consequences and the reflected pressure (pressure measured when the wave is incident perpendicularly on the transducer) measured during fire tests inside a pyrotechnic store indicated the need to minimize the potential occurrence of fires. The limitation of the maximum permissible load, considering the volume of the store (kg/m3), reduces consequence severity in the event of an accident. However, the maximum permissible levels should be so low as to make their use for retail sales of pyrotechnic products unviable. The solution is the use of automatic fire detection and extinguishing systems with a high cooling capacity in order to prevent the spread to nearby packaging by rapid detection.

Improving Passive Safety in Electric Vehicles by Developing a Prototype of Automatic Fire Extinguishing System

Electric vehicles (EVs) are becoming increasingly popular due to their eco-friendliness and fuel efficiency. However, they pose a potential fire hazard due to their high-voltage battery packs. In this paper, we present a prototype of an automatic fire extinguisher system for EVs using an Arduino UNO board, a fire sensor, and a wiper motor. The proposed system consists of a fire sensor that is fixed near the battery pack to detect any signs of fire. The sensor sends a signal to the Arduino UNO board, which in turn triggers the wiper motor. The motor is connected to a gear system that opens the cylinder of the fire extinguisher, releasing the extinguishing agent onto the fire. The prototype was tested in a simulated environment, and the results showed that the system was able to detect the fire and trigger the extinguisher in less than 5 seconds. The system can also be easily installed in any EV, as the sensors can be fixed at desired locations depending on the vehicle's design. The proposed system has several advantages over traditional fire extinguishing systems, such as being fully automated and requiring minimal human intervention. It can also help reduce the risk of fire-related accidents in EVs, ensuring the safety of passengers and the vehicle. In conclusion, the prototype of an automatic fire extinguisher system for EVs presented in this paper has the potential to improve the safety of electric vehicles and can be further improved by integrating additional sensors and safety features

Программный робот-проектировщик для выбора автоматических установок пожаротушения

Автоматические установки пожаротушения (АУП) широко применяются для защиты пожароопасных объектов, при этом выпускается большое количество АУП разных типов. Актуальная задача для проектировщиков – выбор АУП, обеспечивающих эффективную защиту объекта. Для выбора оптимального варианта важно провести сравнительную оценку возможных типов АУП. Для решения этой задачи предлагается использовать программный робот-проектировщик RPA. Разработана автоматизированная программа выбора АУП, которая выполняет функции робота-проектировщика, а пользователь ведет с ним диалог по исходным данным, оценке и выбору предлагаемых вариантов. Automatic fire extinguishing systems (AFESs) are the basis for the protection of fire-hazardous facilities. Currently, a large number of AFESs of various types are produced. The issue of selecting AFES is of significant importance because it influences both the cost of the technical means used and the efficiency of the facility protection. Recommendations for the choice of automatic fire extinguishing system are given in the VNIIPO paper “Selecting the type of automatic fire extinguishing systems”. The calculation of technical means and efficiency indicators is carried out for each type of AFES for the comparative evaluation in accordance with these recommendations. The calculations are entered manually and require considerable time with the assistance of specialists. The estimated figures used are difficult to compare and are very approximate for the comparative analysis, because they are based on average data. The human factor has a significant impact on the objectivity of the evaluation. Automation of calculations, according to the established methods of calculation, would greatly simplify the selection of the AFES and make the choice objective. The use of estimated figures based on actual data increases the reliability of the evaluation significantly, including the starting of fire extinguishing response time and the response time of fire extinguishing process, being the most optimal criteria for evaluating the efficiency. The possibility of using AFES, accepted in SP 485.1311500.2020, should also be taken into account, including the rate of combustion propagation of combustible materials used. During the evaluation it is reasonable to take into account the damage from a fire, determined, for example, by the area exposed to fire. Reliability is the most important indicator of the AFES efficiency. Nowadays, program-controlled RPA robots are widely used to perform the control functions of typical processes in a dialogue with a human. The challenge was set to create a program-controlled robot for selecting the AFES, according to the initial data of the protected facility, being the same for all used AFESs. The robot performs an independent automatic evaluation of technical means and selection of the optimal AFES according to comparable estimated figures, based on actual data for all AFESs simultaneously. An automated program for selecting AFES was developed to accomplish this task. The program performs the functions of a program-controlled robot (Certificate of state registration No. 2022664536), and is presented in the Internet web application available at: https://firerobots.ru/calculate. A unified approach based on the general requirements of the code of practice SP 485.1311500.2020 makes it possible to compare different fire extinguishing systems. The initial data of the protected facilities entered into the program, and the system makes calculations of technical means, and determines the estimated figures for effective fire extinguishing. The proposed technical solutions make it possible to create an AFES selection system using a service program that performs the functions of a design robot, including: interactive input of information, automated calculations in accordance with regulatory requirements and calculation formulas, receiving the necessary objective evaluation data on efficiency and pricing, selection of the optimal AFES from a number of AFESs used for the protection of facilities

Fearless design on the gas leak (fire suppression and smart alert system)

The purpose of this research is to design an automatic leak detection and fire extinguishing system called FEARLESS. The method used is a case study methodology and applied. From the data obtained in the field, it was found that there were 4 gas detector disturbances in 2019 and 5 times in 2020 which resulted in no detection of gas leaks when the detector was disturbed, as well as 34 gas leaks in 2019 and 42 times in 2020. From this data, it is used as a reference in designing the FEARLESS (FIRE SUPRESSION AND SMART ALERT SYSTEM) to detect gas leaks. The application of the FEARLESS system can be drawn several conclusions, including applying the FEARLESS system can reduce the failure or damage that occurs so as to minimize the occurrence of undetected gas leaks. The FEARLESS system can be combined with two or more detectors to be implemented for various needs.

Special aspects of design solutions for indoor water supply systems of high-rise buildings

Introduction. The subject of research is indoor cold water supply systems of high-rise buildings. They have a complex structure due to unique architectural features, the need to pump water to higher floors and compliance with reliability requirements applicable to engineering systems. High-rise buildings are often multi-functional, and this characteristic is implemen­ted in the process of designing indoor water supply systems: it is necessary to take into account various classes of functional fire hazards typical for different areas inside a building, and equip individual rooms with automatic water extinguishing units. Of special importance is the energy efficiency of a water supply system, since pumping equipment and its mode of operation have the greatest influence on the system. The design of an indoor water supply system for any high-rise structure is always a compromise between the interests of investors (developers) and the regulations. The purpose of the study is to identify current trends in the design of indoor cold water supply systems for high-rise buildings (or complexes).
 Materials and methods. The overview is based on current regulatory and engineering documentation governing high-rise construction, as well as the research papers focused on the design of engineering systems of high-rise buildings. The author analyzed several designs of indoor water supply systems for multi-functional high-rise buildings, in respect of which positive opinions had been issued by the expert organizations.
 Results. It is established that up-feed parallel water supply systems, broken down into zones, are most widely used in the present-day projects of indoor water supply systems designed for high-rise buildings. Each water supply zone can serve 11 to 18 floors, and an increase in the number of floors within one zone reduces the energy efficiency of the system. Automatic fire extinguishing systems are an integral element of water fire extinguishing systems in multi-functional high-rise buildings. Any damage, inflicted by the false triggering of sprinklers, should be minimized at the stage of design.
 Conclusions. The author classified potential cold water supply systems for high-rise buildings, described their principle of operation, strengths, weaknesses, and applicability limits. The research project also encompasses the analysis of present-day designs of indoor cold water supply systems for multi-functional high-rise buildings.

Импульсное пожаротушение - состояние вопроса

Проведен анализ имеющихся разработок средств пожаротушения, основанных на импульсном способе подачи огнетушащего вещества (ОТВ). Сделаны предположения о механизме прекращения горения при подаче ОТВ в очаг пожара импульсным способом. Отмечена перспективность применения импульсного способа подачи ОТВ в различные очаги возгорания. Принцип построения импульсного пожаротушения позволяет легко составлять конфигурацию под различные требования, а также дает возможность наращивания существующих систем противопожарной защиты. The problem of eliminating fires spreading over large areas in closed and semi-closed spaces (warehouses, cable channels, high-rise buildings, etc.) is important and difficult to solve. Firstly, it is difficult to get close to such fire, therefore it is necessary either to solve the problem of supplying extinguishing agents from a long distance which complicates the fire extinguishing process or to install automatic fire extinguishing systems in close proximity to the source that is very difficult due to potentially destruction by possible explosions. Secondly, in order to suppress a developed fire from a long distance it is necessary to supply extinguishing agent continuously for a long time or to supply a large amount of extinguishing powder directly to the flame source at the same time. It is a very difficult task since it is necessary to get into a small diameter relative to the distance to it. The aforesaid suggests that it is necessary to investigate various ways of supplying a fire extinguishing agent. The paper provides an overview of the development of fire extinguishing means based on a pulse method of supplying the extinguishing agent to the ignition source. Currently special attention is paid both to the development of such technologies and to the creation of such fire extinguishing tools that would allow suppressing fire without coming into direct contact with it. Direct contact with fire means that a person exposes to a number of fire hazards: high temperatures, lack of air and visibility, risks associated with the unpredictability of the situation. In some cases, successful suppression of the source of combustion can be ensured by means and methods of extinguishing that allow remotely supplying of fire extinguishers directly to the combustion zone in a short period of time (1-2 s) in the amount necessary to suppress the fire. The pulse supply method developed and implemented in various kinds of devices meets this requirement in terms of its potential capabilities.

Особенности применения методики оценки возможности использования спринклерных АУП (приложение «В» к СП 485.1311500.2020)

Рассмотрены особенности практического применения Методики оценки возможности использования спринклерных АУП, входящей в состав СП 485.1311500.2020 (приложение В). Методика позволяет: выявлять вероятную причину неэффективной работы спринклерной автоматической установки пожаротушения (активировалась при пожаре, но не выполнила свои функции); проводить экспертизу ранее спроектированной и смонтированной автоматической установки пожаротушения для оценки возможности ее эффективной работы при пожаре в защищаемом помещении; давать рекомендации проектировщику спринклерной автоматической установки пожаротушения по выбору способа активации при пожаре - от теплового разрушения запирающей колбы или по сигналу от дифференциального теплового извещателя. Приведены примеры применения Методики. The prerequisite for writing this article were cases when automatic sprinkler fire extinguishing systems (ASFES) triggered during a fire in a room, but did not perform their functions - as the sprinklers with locking flasks were activated, the fire continued anyway. At the same time, the subsequent analysis revealed no violations either during the design of the ASFES in accordance with SP 5.13130.2013, or during the installation of the ASFES, or during the maintenance of the ASFES. The reason for the ineffective operation of the ASFES turned out to be the following. The height H of the rooms protected by the ASFES was so high that convective flows from burning products, rising up, cooled to a temperature insufficient for timely sprinkler activation. They were activated belatedly when the fire area was already larger than the area protected by the sprinkler. The fire area increased and the ASFES sprinklers continued to be activated by the "domino effect". As a result, ASFES could not fulfil its main function - to suppress burning in a timely manner. Understanding of such a process led to the need to develop a special "Methodology for assessing the possibility of using ASFES", which was issued in the form of Appendix B to SP 485.1311500.2020 "SPP. Fire extinguishing installations are automatic. Norms and rules of design". In Appendix B there were used mathematical expressions to solve the following tasks: a) to identify the probable cause that the sprinkler ASFES worked in a fire but did not perform its functions; b) to carry out an examination of the previously designed and installed ASFES for the purpose of assessing the possibility of its effective operation in case of a fire in the protected room; c) to give recommendations to the designer on the choice of the method of switching on the sprinkler ASFES in case of fire. However, the limited volume of SP 485.1311500.2020 did not allow to give examples of calculations in Appendix B, which made it difficult to use Appendix B. The purpose of this article is to maximize the ease of application of Appendix B to SP 485.1311500.2020 by providing computational examples of solving problems "a-b" and thereby ensuring the design of effective sprinkler ASFES.

Research on the reliability of automatic fire alarms and their impact on safety in refinery

Safety of oil refineries (refineries) in the field of fire safety should be provided by the fire safety system, which, in accordance with regulatory legal acts, includes fire automation systems. Automatic fire alarm is the very first, responding to fire signals, installation of fire automation. At the same time, the unstable operation of automatic fire alarm and fire extinguishing systems destabilizes the operation of the automated control system, reducing the overall efficiency of the facility. In the article, a study and analysis of the causes of false positives of Automatic fire extinguishing systems at refineries and deaths during fires at refineries was conducted.

Анализ возможности применения автоматических установок пожаротушения для электрооборудования под напряжением на объектах энергетики

Introduction. The article considers the possibility of solving the problem of using automatic fire extinguishing systems to extinguish electrical equipment under voltage in rooms with no people. Examples of fires at energy facilities in recent years are considered, as well as statistics of fires at transformers in the Russian Federation in the period from 2016 to 2021. The analysis of normative legal acts of the Russian Federation and foreign analogs is carried out. As a result of the analysis, the problem of using automatic fire extinguishing installations at energy facilities has been identified. Targets and goals. The purpose of the study is to analyze the possibility of using automatic fire extinguishing systems for live electrical equipment at energy facilities. During the study, the following tasks were set: - analysis of regulatory legal acts of the Russian Federation and international standards in the field of extinguishing Class E fires; - analysis of fire statistics at transformer substations in the Russian Federation in the period from 2016 to 2021; - development of the concept of a test bench to determine the leakage current through the jet of fire extinguishing agent from automatic fire extinguishing installations when extinguishing electrical equipment under voltage. Methods. When conducting a study on the use of automatic fire extinguishing installations for live electrical equipment at energy facilities, the analysis method was used. Results and its discussion. As a result of the study, the problem of rationing and the use of automatic fire extinguishing installations for electrical equipment under voltage in rooms with no people was identified. The concept of a test bench for determining the leakage current through a jet of fire extinguishing agent from automatic fire extinguishing installations when extinguishing live electrical equipment is proposed. Conclusions. During the study, it was revealed that international standards and norms in the Russian Federation diverge in the field of application of automatic fire extinguishing installations for live electrical equipment at power facilities, therefore, further research and development of the proposed test stand is necessary to determine the leakage current through the jet of fire extinguishing agent from automatic fire extinguishing installations, which will allow to explore the possibility of using various types of automatic fire extinguishing installations, with different types of fire extinguishing agents to eliminate fires in electrical equipment under voltage. Keywords: automatic fire extinguishing installations, fire electrical equipment, fire protection, transformer, test bench.

Design Analysis and Implementation of Automatic Fire Extinguishing System Using ATmega16 Microcontroller as Control

Aim: The aim of this research is to design an automatic fire detection and control.
 Methodology: The system consists of two sensors, microcontroller, buzzer and a pump/sprinkler. An LM35 integrated chip has been used as temperature sensor while MQ-2 gas sensor has been used as smoke sensor. All sensors are connected to the microcontroller through an input/output port. The controlling software for the whole system was designed in C programming language. The popular high performance, low power 8-bit microcontroller from the AVR family microcontrollers has been used. The system was finally tested by introducing fire parameters (smoke and temperature) close to the smoke and temperature detectors respectively. When the parameters go above the set level in the detectors, audio alarm, light indicator and pump/sprinkler were activated. The measured temperature of the system was compared with the reference temperature. 
 Results: The result showed that there was a mean deviation of 1.550C between the measured values and reference values which served as the control. 
 Conclusion: The constructed system is compact and easy to install. The constructed fire control device is quite cheap and affordable to every category of person.

The Problem of Fire Control by Automatic Fire Extinguishing System

According to Article 117 of Russian Federal Law 123 of 2008, there is a class of objects historical buildings, exhibition complexes, energy facilities, etc. For these objects, it is not so necessary to eliminate the fire with automatic fire extinguishing systems, as to contain it until the arrival of fire departments. However, this law does not specify certain requirements for automatic installations, the main working substance of which is water and the solutions. The current situation makes it difficult to design, install and test automatic fire control systems. Given this, as well as the foreign experience and domestic developments in the field of automatic fire extinguishing systems, it is important to conduct a special research work. In this work, it is necessary both to conduct several fire tests in terms of the development of a fire with a limited water supply intensity, and to develop a draft of standard “Water automatic fire containment installations. General technical requirements. Test methods”.

Еlectronic fire safety systems efficiency in the combustion zone of cars for underground parkings of residential buildings

In this paper we presents the results of tests of automatic fire alarm systems in terms of reducing the temperature effect on building structures (floors), air ducts of the exhaust smoke ventilation system. Tests were carried out to determine the efficiency of the antismoke ventilation system for the removal of combustion products through steel air ducts with a metal thickness of 1 mm, as well as analysis of the temperature regime on building structures, the air duct of the exhaust smoke ventilation system under fire exposure. For the warning system (SO) of the second type, CO-2 we used on the basis of ISO “Bolid” devices. The launch of a fire warning system is provided for: automatically from an automatic fire extinguishing system; remotely from manual fire detectors installed at emergency exits from the vehicle storage room. Two full-scale firing tests were carried out for passenger cars. During the tests, the vehicles were ignited from inside the passenger compartment. In the course of the fire tests proved that the antismoke control ventilation ducts retained their integrity and tightness, which was confirmed by the positive protocols of aerodynamic tests of the smoke control ventilation system. The air ducts of the exhaust smoke ventilation system retained their integrity, the flange connections of the air ducts retained their strength and tightness, the fastenings of the air ducts were not damaged and retained their functions. The tests established the following: limitation of the fire center in the horizontal projection of the vehicle (the perimeter of the vehicle); filling the volume of the storage room for vehicles with a smoke-steam-air mixture occurs in an avalanche manner over the entire height of the room; as a result of the avalanche-like filling of the room, the absence of a neutral zone (security zone) was determined. Based on the results of the tests, it is possible to make changes to the existing technical normative legal acts.

Project concepts for combined fire-extinguishing systems

Based on the analysis of the functioning of the sprinkler fire-extinguishing system and the chemical reaction of the interaction of ammonia with water, the article considers the formation of an integrated fire extinguishing system to ensure the safety of processes and production plants where ammonia is used in the main and auxiliary processes. Analysis of the functioning of the system allows creating a project for a unified combined fire-extinguishing system based on an automatic sprinkler system and including the function of reacting and responding to the presence of ammonia vapors in the air of the production rooms. The paper proposes a supplement by the method of aggregation of automatic sprinkler systems with ammonia sensors, which, while maintaining the basic fire extinguishing function, can suppress emergency ammonia releases. As an example, the paper describes the formation of the project of a combined automatic sprinkler fire-extinguishing system with ammonia sensors and implements an additional function to ensure production safety in case of a possible ammonia emergency release.

Расчетная оценка геометрических параметров спринклерных установок водяного пожаротушения высотных стеллажей

Рассмотрены вопросы, связанные с применением спринклерных автоматических установок водяного пожаротушения стеллажей. Проанализированы соответствующие нормативные документы. Описаны варианты решения задач определения расхода воды из оросителя, координат места его установки, а также углов распыла огнетушащего вещества и наклона оси оросителя. Приведены примеры расчета геометрических параметров спринклерных автоматических установок водяного пожаротушения стеллажей. Fires at objects whith high-rack storage of combustible materials are particularly dangerous because of the rapid spread of the flame vertically, the risk of collapse of the racks and the damaging effects of high temperature on structural elements of the building. The main method of extinguishing such fires at the initial stage is the use of automatic sprinkler fire extinguishing systems (AUP). The requirements for AUP parameters (types of detectors and sprinklers, their characteristics and distances) depending on the height of the room and storage are currently set out in two normative documents: the set of rules (SP 241.1311500.2015) and the organization standard (VNPB 40-16). Unlike the SP, where there is provided only the supply of a fire extinguishing substance (FES) - water vertically down with high-flow sprinklers of type SOBR (ESFR) and there are no requirements for the type of fire detectors, VNPB provides the use of different types of detectors (aspiration, smoke, heat), forced start-up of AUP sprinklers, which reduces the time of free fire development and the supply of FES by a flow shaper with the spray angle ≈ 600 at an angle  to the vertical both to the horizontal and lateral surfaces of the racks. This article discusses the issues of determining the parameters of automatic sprinkler systems for water fire extinguishing of racks. Variants of solving synthesis problems are given - the choice of the places for installing sprinklers depending on the height and width of the racks, their axis of inclination, and also the spray angle. To solve these problems, the computer program called struja.exe was created, a series of calculations on which showed a negligible effect of aerodynamic drag due to relatively small distances. Examples are given. Thus, the features of the sprinkler AUP for the protection of rooms with high-rack storage and the task of determining its geometric parameters are considered. In this case, forced activation of the sprinkler follows in order to avoid a delay in the start of extinguishing. In the future, it is also desirable to conduct additional field experiments with sprinkler water supply and also (if possible) evaluate the effect of ascending flows of combustion products on the water flow from the sprinkler.

АНАЛИЗ ПРИЧИН ЛОЖНЫХ СРАБАТЫВАНИЙ СИСТЕМ АВТОМАТИЧЕСКОЙ ПОЖАРНОЙ СИГНАЛИЗАЦИИ И АВТОМАТИЧЕСКИХ УСТАНОВОК ПОЖАРОТУШЕНИЯ

The reasons for false alarms of automatic fire alarm systems and automatic fire extinguishing systems are analyzed, and recommendations for reducing the number of false alarms are proposed