scholarly journals A Study on the Durability of Fire Hoses of Fire Hydrants

2021 ◽  
Vol 21 (6) ◽  
pp. 97-102
Author(s):  
Hakjoong Kim ◽  
Youngjoo Song

Although the number of fires has not changed considerably in recent times, property damage and casualties due to fires are increasing every year. Maintaining the performance of fire-fighting facilities installed in buildings has been emphasized for maximizing human safety and minimizing property damage caused by fires. As a result, since 2017, the maintenance of fire extinguishers throughout their service life, has been mandated. In case of a fire, initial fire extinguishing and fire spreading prevention are crucial. There have been no available measures for the maintenance and verification of indoor fire hydrants and outdoor fire hydrant hoses used for extinguishing fires and preventing combustion expansion. This study was therefore intended to present measures for ascertaining the service life of these fire extinguishers, by evaluating their firefighting abilities through sample analysis and case analysis of the fire hoses. Research shows that the degradation of performance of the fire hoses becomes evident between 9 and 10 years, so that 10 years of service life is considered appropriate for the fire hoses.

2020 ◽  
Vol 20 (2) ◽  
pp. 95-104
Author(s):  
Euipyeong Lee

The problems and safety measures for magnesium fires were analyzed based on the fire case analysis in this study. The following problems were analyzed: ① the fire occurs in areas where there is no regulation under the Hazardous Goods Safety Management Act, ② the lack of safety measures during the firefighting of magnesium fires, ③ absence of adaptive fire fighting agents or equipment, ④ absence of suitable fire fighting tactics. For safety measures, the following were analyzed: ① enactment of magnesium fire guidelines, ② the education and publicity regarding fire prevention and countermeasures by fire organizations, ③ the obligation to have appropriate fire extinguishing agents in the places where magnesium is stored and handled, ④ the development of suppression equipment and fire fighting tactics, and ⑤ the research and development of fire extinguishing agents.


Fire Safety ◽  
2019 ◽  
pp. 53-59
Author(s):  
V. Kovalyshyn ◽  
V. Marych ◽  
B. Gusar ◽  
V. Navalianyi ◽  
Ya. Fedyuk

The analysis of the problem of extinguishing fires of magnesium and its alloys is carried out. The urgency of studying the problem is confirmed by the fact that during the extinguishing of class D fires there are factors that can complicate the quenching process. Often, these metals actively react with water, which leads to an even greater spread of the fire and even an explosion. Therefore, special fire extinguishers, which have passed the proper test, are more effective in locating the fire and prevent the burning of the powder to form the "tongues" of the flame. In Ukraine, there is no method for testing the effectiveness of fire extinguishants of special purpose for the extinguishing of class D fires. The normative documents have been analyzed, which specify the procedures for testing extinguishing fire-extinguishing special-purpose fire extinguishing class D. Specifically: the methods are described in the international standard ISO 7165: 2017 «Fire fighting – Portable fire extinguishers – Performance and construction» and GOST 53280.5-2009 Fire fighting systems automatic. Extinguishing agents. Both methods have a number of shortcomings that need to be addressed when creating a Ukrainian fire test method for extinguishing fire extinguishing class D, namely: the dimensions of the metal frame made of sheet steel with a side (500 ± 10) mm, height (150 ± 5) mm for testing with magnesium chips are small; Not specified quantity of gasoline necessary for the rise of magnesium; The gas or oxygen torch used to dissolve magnesium does not provide full-value combustion throughout the area, but only creates separate cells of ignition. A draft methodology has been developed that determines the fire-extinguishing efficiency of powdered powders used in Ukraine. The required amount of fuel for burning magnesium and its alloys is determined. It was ascertained that for the firing of magnesium chips it is necessary to use at least 127 grams of gasoline of the mark A 92. Key words: test method, fire extinguishers of special purpose, extinguishing of fires of magnesium alloys


2011 ◽  
Vol 130-134 ◽  
pp. 1054-1057
Author(s):  
Chang Sheng Liu

The fire fighting equipments used for fight forest and grassland fire of China are mainly small two-stroke gasoline-powered portable wind fire-extinguishers owing to these areas are located in the more remote and inaccessible, where generally stay away from water. The main drawback of the wind fire-extinguisher is that it would lower the efficiency of power attributed to overheating of the two-stroke gasoline engine in the long process of firefighting, which will lead to decline the output speed and volumetric flow of fire extinguishing wind drived by the turbine when fire ambient temperature is high in the spring and summer. If this situation occurs, it will reduce efficiency of its fire fighting, what is more the adverse effects of wind to help the fire rather than put out the fire because the output of the extinguishing wind speed and volumetric flow is too small. In order to avoid the occurrence of such adverse effects and improve the extinguishing effect of fire extinguishers in the long process of firefighting, a program which use CO2 coordinate with wind fire-extinguisher to put out a fire was proposed in this paper, and the structure, characteristics of operation and precautions of the CO2 fire-extinguisher were described detailly.


2020 ◽  
Vol 12 (4) ◽  
pp. 290-295
Author(s):  
V. V. Nikiforov ◽  
M. V. Aleshkov ◽  
I. A. Gusev

Fires and accidents at nuclear power facilities that occurred in the past resulted in considerable property damage, both direct and indirect one. The emerging threats had a negative impact on the fire-fighting process that had to be interrupted, which contributed to spreading of fire. One way of solving the problem is to develop and use robotics, and in order to achieve the effectiveness of robotics equipment, this must be designed taking into account the specifics of the facility, where it is planned to be used, and operate throughout the plant premises, while being of the light class. Having analyzed the peculiarities of origination and development of fires at NPPs, as well as taking into account the specifics of the facility, technical requirements for the design of the robotic equipment were developed, which formed the basis for the creation of a prototype implemented in a mobile robotic fire-fighting unit (MRUP). In order to check the stated tactical and technical characteristics, MRUP was subjected to tests for its running performance, operability of its components and assemblies, and fire-extinguishing properties. The test of running performance was carried out on dedicated stands with a variety of inclined surfaces, climbing angles and heights. For MRUP firefighting efficiency to be tested, a model hotspot was extinguished, the range of delivery and the consumption of fire-extinguishing agents were measured.


Author(s):  
V.N. Bordakov ◽  

Test-fires to determine fire-extinguishers’ efficiency for extinguishing B class fires are conducted by operators equipped with working clothes, which does not comply with the requirements of physical modelling. This is why the ranks of extinguished modelled seats are significantly overestimated. The quantitative results of fire seats’ extinguishing can be comparatively evaluated in accordance with the value of specific flow rate of a fire-extinguishing agent. As it was detected, the specific flow rate of a fire-extinguishing agent does not actually depend on the rank of modelled fire seat when extinguished by an operator wearing thermal-protective clothes. At the same time, it is increasing along with the expansion of the fire zone scale in case the fire is extinguished without special protective clothes. Consequently, to increase the fire-extinguisher’s efficiency data reliability, the certifying tests should be conducted in conditions close to the real application conditions when the first person to firefight is not equipped with such special protective clothes. The experimental studies to determine the specific flow rate of a fire-extinguishing agent used modelled fire seats of various ranks. The analysis of results showed that the fire-extinguishers ensuring generation of drops of prevailing size more than 0,5 mm are required to extinguish the modelled sire seats. The degree of increasing flow rate for the fire-extinguishing agent to eliminate a fire and observation of a safe distance from the flame for an operator are conditioned by the scale of fire zone and affect the specific flow rate of agent required to ensure stable fire-extinguishing. Based on the results of extinguishing the fire seats «34В» or «55В», it is demonstrated that via using a correction factor it is possible, assuming an acceptable error, to evaluate the flow rate of fire-extinguishing agent to extinguish a modelled fire seat of any rank.


2020 ◽  
pp. 142-146
Author(s):  
В.А. Наумов ◽  
Н.Л. Великанов ◽  
А.В. Тришина

Цель статьи – получить эмпирические зависимости для характеристик трехплунжерных противопожарных насосов (ТПН), необходимые для автоматизации расчетов систем тушения пожаров на судах с применением распыленной морской воды. Задачи исследования: проверка непротиворечивости данных испытаний; определение расчетных зависимостей производительности ТПН, к.п.д., затраченной мощности от давления. Проведенный анализ результатов испытаний ТПН подтвердил возможность использования предложенных зависимостей в инженерных расчетах. Данные измерений удовлетворительно согласуются с результатами расчетов, за исключением к.п.д. Отклонение экспериментальных точек от эмпирических зависимостей, скорее всего, связано с занижением значений затраченной мощности на испытаниях при небольших давлениях. Предложено для оценки к.п.д. использовать ранее полученную типовую зависимость. Построены графики для характеристик насоса NP25/41-170S. Пример расчета рабочей точки насосной установки с использованием приближенной гидравлической характеристики водяной пожарной системы судна показал высокую эффективность предложенных методик. The purpose of the article is to obtain empirical dependences for the characteristics of three-plunger fire-fighting pumps (TFP), which are necessary for automating calculations of fire extinguishing systems on ships using sprayed seawater. Research objectives: checking the consistency of test data; determining the calculated dependences of the TFP performance, efficiency, power expended on pressure. The analysis of the TFP test results confirmed the possibility of using the proposed dependencies in engineering calculations. The measurement data are in satisfactory agreement with the results of calculations, with the exception of efficiency. The deviation of experimental points from the empirical dependences is most likely due to an underestimation of the power consumed during tests at low pressures. It is proposed to use the previously obtained typical dependence to estimate the efficiency. Graphs are plotted for the characteristics of the NP25/41-170S pump. An example of calculating the working point of a pumping unit using the approximate hydraulic characteristics of the ship's water fire system showed the high efficiency of the proposed methods.


Author(s):  
Azzaya T ◽  
Burmaa G ◽  
Alen S ◽  
Batsaikhan V

Water, foam, dry powder, carbon dioxide and liquid chemicals are used as fire extinguishers depending on the fire types. The fire classification of ABC type includes fires caused by paper, wood, dye, fuel, oil, lubricants and flammable gases. In this work, the investigation of the procedure for re-determining the composition of prepared fire extinguishers was carried out depending on the ratio of organic and inorganic substances, and their fire extinguishing activity was tested. The Sample-1 contains about 50% of ammonium dihydrophosphate (NH4H2PO4) which is taking into account the main component and the sum of ammonium sulphate (NH4)2SO4 and other inorganic and organic components by 50%. As a result of fire extinction tests, its fire extinguishing activity was higher than that of other Samples included different ratios of substances. Based on the thermogravimetric analysis of the Sample -1, the polymerization and water release process of NH4H2PO4 was detected as endothermic effect. The weight loss was occurred by 74% and 26% remained as P2O5 when temperature reached to highest degree. Some physical parameters such as moisture content, water repellence, density and particle size were analyzed according to ISO standard method and all these important parameters showed that it can meet the requirements for fire extinguishing powder standards. Гал унтраагч шинэчилсэн бэлдмэлийн найрлага, түүний физик шинж чанарын судалгаа Хураангуй: Ус, хөөс, хуурай нунтаг, нүүрс хүчлийн хий ба химийн шингэн бодис зэргийг галын төрлөөс хамааруулан гал унтраагчаар ашигладаг. Галын ABC ангилалд цаас, мод, будаг, шатахуун, тос, тосолгооны материал, шатамхай хий зэргээс үүдэлтэй гал хамаарна. Энэхүү ажлаар импортын гал унтраагч бодисын найрлагыг шинэчлэн тогтоох судалгааг органик ба органик бус химийн бодисуудын харьцаанаас хамааруулан явуулж, тэдгээрийн гал унтраах идэвхийг ABC ангиллын галд туршив. Үндсэн бүрдэл болох аммонийн дигидрофосфат (NH4H2PO4)-ыг 50%, (NH4)2SO4 ба бусад бүрэлдэхүүн бодисуудын нийлбэрийг мөн 50%-иар тооцоолон авсан. Бэлдмэл 1-ийн гал унтраах идэвх нь бусад бэлдмэлүүдийн идэвхээс өндөр байв. Бэлдмэлийн термографийн судалгаагаар NH4H2PO4-ын их хэмжээний дулаан шингээн полимержих, ус ялгаруулах процесс DTA-ийн муруйд эндо эффект хэлбэрээр илэрсэн ба температурын дээд утгад жингийн алдагдал 74%-д хүрч, 26% нь P2O5 хэлбэрээр үлдсэн. Гал унтраагч нунтгийн физик шинж чанарын гол үзүүлэлтүүд болох чийг, хувийн жин, ус үл нэвтрүүлэх чадвар, ширхэглэлийн хэмжээг тодорхойлсон ба эдгээр үзүүлэлтүүд нь стандартын шаардлагуудыг хангасан байна. Түлхүүр үг: Гал унтраагч нунтаг, идэвх, аммонийн дигидрофосфат, DTA/TG, физик үзүүлэлт  


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