Fire extinguishing test method and fire extinguishing test apparatus

Abstract

This invention provides a fire extinguishing test method and fire extinguishing test apparatus that can evaluate the fire extinguishing capacity of a single throwable, simple fire extinguishing device (sample). [Solution] The process is carried out through the following steps: firstly, setting up a fire model (Type-I model, Type-II model) formed by stacking a predetermined number of rectangular prism-shaped pieces of wood in a predetermined manner, igniting fuel, and burning the fire model through the fuel; secondly, after the fuel has been extinguished and at the start of firefighting activities during the steady combustion of the fire model, using a smashing device 100, which serves as a fire extinguishing test device, to strike the top of the fire model with a throwable specimen filled with fire extinguishing agent; thirdly, determining whether the fire has been extinguished or has failed after a predetermined time has elapsed since the fuel was ignited; and fourthly, repeating the first, second, and third steps to derive the maximum fire extinguishing area of ​​the specimen based on the maximum number of fire extinguishing stages of the fire model.

Description

[Technical Field]

[0001] The present invention relates to a fire extinguishing test method and a fire extinguishing test apparatus used for throwing specimens in which a fire extinguishing agent is filled into a container. [Background technology]

[0002] A conventional hand-thrown fire extinguishing liquid projectile (sample) is described in Patent Document 1. According to this, the fire extinguishing liquid was sealed in a container made of thin resin or similar material that could be easily thrown by hand and was resistant to impact. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 09-253231 [Overview of the project] [Problems that the invention aims to solve]

[0004] In Patent Document 1, the "Ministerial Ordinance for Establishing Technical Standards for Fire Extinguishers" (Ministry of Home Affairs Ordinance No. 27 of September 17, 1964) is described as a fire extinguishing test for the fire extinguishing performance of the above-mentioned hand-thrown fire extinguishing liquid projectile (sample), but in some cases multiple samples were required to extinguish a single model (second model).

[0005] Furthermore, in the fire extinguishing tests described above, the samples were thrown by people at a fire model. However, in reality, when thrown by people, the speed and force are not constant, which could lead to an inaccurate evaluation of the fire extinguishing performance of the samples.

[0006] In view of the above circumstances, the present invention provides a fire extinguishing test method and a fire extinguishing test apparatus that can evaluate the fire extinguishing capacity of one throwable simple fire extinguishing device (sample).

[0007] Furthermore, as a secondary benefit, this invention provides a fire extinguishing test method and apparatus that can accurately evaluate the fire extinguishing performance of a specimen by keeping the speed, force, etc., of the specimen constant relative to the fire model. [Means for solving the problem]

[0008] The invention described in claim 1 involves a first step of setting up a fire model, which is formed by stacking a predetermined number of rectangular prism-shaped wooden pieces in a predetermined manner, in a predetermined manner, igniting fuel, and burning the fire model through the fuel, After the fuel has been extinguished, and at the start of firefighting activities during the steady combustion of the fire model, a second step is taken in which a throwable sample, which contains a container filled with fire extinguishing agent, is attached to a fire extinguishing test apparatus and the sample is struck against the upper part of the fire model. A third step involves determining, after a predetermined time has elapsed since the ignition of the fuel, whether the fire has been extinguished or the extinguishing attempt failed. The first, second, and third steps are repeated, and a fourth step is performed to derive the maximum fire extinguishing area of ​​the specimen based on the maximum number of fire extinguishing stages of the fire model. It will be carried out after the following steps.

[0009] This allows for accurate evaluation of the fire extinguishing performance of each individual sample.

[0010] Furthermore, the first step is performed in advance, the fire model is allowed to burn until it is extinguished, and the rate of heat generation of the fire model is measured. The steady-state combustion described above is defined as ending when the heat generation rate reaches its maximum value in the latter half of the stable section after the fuel has been extinguished, and starting when the first time a value approximating the maximum value in the latter half of the heat generation rate is measured. The start time of the firefighting operation is derived based on the time elapsed since the fuel was ignited.

[0011] According to this method, the start time of firefighting activities in the fire model can be determined by eliminating the influence of the combustion of the fuel used to ignite the fire model.

[0012] Furthermore, the first step, the second step, and the third step are performed in advance. A minimum stage setting step is performed to derive the minimum number of stages of the fire model based on the heat release rate of the fire model and the time from ignition of the fuel.

[0013] According to this, the fire model can facilitate the determination of from which stage the test should be started.

[0014] Further, a fire extinguishing test apparatus used in the fire extinguishing test method according to any one of claims 1, 2, and 3, a main body portion, a mounting rod body pivotally supported by the main body portion and capable of mounting the specimen, a receiving member for receiving the mounting rod body, and comprising: The mounting rod body is movable between a collision position where the upper portion of the fire model and the specimen collide and a standby position where the specimen is held and waits above the fire model. It comprises holding means for holding the mounting rod body in the standby position, and by releasing the holding state of the holding means, the mounting rod body can move from the holding position to the collision position by its own weight.

[0015] According to this, the speed, force, etc. of the specimen with respect to the fire model can be made constant, and the fire extinguishing performance of the specimen can be correctly evaluated.

[0016] Further, an urging member is provided that is spanned between the main body portion and the mounting rod body and assists in moving the mounting rod body from the standby position.

[0017] According to this, when the mounting rod body is arranged vertically, if only the holding state of the holding means is released from the standby position, the mounting rod body may not move. However, by assisting the movement from the stationary state by the urging member, it is possible to prevent the case where the mounting rod body does not move.

Brief Description of the Drawings

[0018] [Figure 1]It is a diagram of a model defined in the ordinance (Ordinance of the Ministry of Internal Affairs and Communications No. 26 of 2013) that determines the technical standards for aerosol-type simple fire extinguishers. [Figure 2] It is an explanatory diagram of the Type-I model and the Type-II model in the present invention. [Figure 3] It is an explanatory diagram of a fire extinguishing test apparatus used in the fire extinguishing test method of the present invention. [Figure 4-1] It is an operation explanatory diagram of the fire extinguishing test apparatus. [Figure 4-2] It is an operation explanatory diagram of the fire extinguishing test apparatus and is a continuation of FIG. 4-1. [Figure 5] It is a graph showing an approximation of the heat release rate. [Figure 6] It is an explanatory diagram of a combustion pot and a combustion stand used in the fire extinguishing test method of the present invention. [Figure 7] It is a schematic explanatory diagram of model installation. [Figure 8] It is a graph showing the heat release rate of each model. [[ID=2,6]] [Figure 9] It is a table showing combustion property parameters in each model. [Figure 10] It is a graph showing the definition of steady combustion. [Figure 11] It is a table showing the heat release rates 150 ± 10 seconds after ignition and 180 seconds after ignition for each model. [Figure 12] It is a graph showing the heat release rate of each model in FIG. 8 according to the Heskestad method. [Figure 13] It is a table showing combustion property parameters in each model of the present invention. [Figure 14] It is a graph showing the heat release rate of the lower stage of the Type-II model. [Figure 15] It is a diagram of the test flow of the fire extinguishing test method of the present invention. [Figure 16] It is a diagram of two types of specimens used in the fire extinguishing test method of the present invention. [Figure 17] It is a table showing the results of the fire extinguishing tests of Specimen 1 and Specimen 2. [Figure 18] It is a graph showing the heat release rate at the time of successful fire extinguishing of each specimen and a diagram showing the state of the flame. [Figure 19] This graph shows the rate of heat generation when fire extinguishing fails for each sample. [Modes for carrying out the invention]

[0019] An embodiment of the fire extinguishing test method and fire extinguishing test apparatus according to the present invention will be described with reference to the drawings.

[0020] To conduct a fire extinguishing test on a single throwable fire extinguisher, as mentioned above, the flame scale is too large using the model specified in the "Ministerial Ordinance Establishing Technical Standards for Fire Extinguishers" (Ministry of Home Affairs Ordinance No. 27 of September 17, 1964), making it difficult to extinguish a fire with just one sample.

[0021] Therefore, in this invention, a new model was created based on the model specified in the "Ministerial Ordinance Establishing Technical Standards for Aerosol-Type Simple Fire Extinguishing Devices (hereinafter referred to as the Standards Ordinance)" (Ministry of Internal Affairs and Communications Ordinance No. 26 of 2013) (Figure 1) (described later).

[0022] Furthermore, while the ministerial ordinance stipulates that a person must actually operate the fire extinguisher, it is anticipated that the results of throwable, simple fire extinguishers can vary greatly depending on the user's technique.

[0023] Therefore, in this invention, fire extinguishing is carried out mechanically using a throwable, simple fire extinguishing device with a smashing mechanism.

[0024] Article 4 of the Ministerial Ordinance on Standards outlines the provisions for ordinary fire extinguishing tests as follows:

[0025] Ministerial Ordinance Establishing Technical Standards for Aerosol-Type Simple Fire Extinguishing Devices (Ministry of Internal Affairs and Communications Ordinance No. 26 of 2013) (Fire extinguishing performance) Article 4. Aerosol-type portable fire extinguishers must have one or more of the fire extinguishing capabilities listed in the following items. 1. Fire extinguishing performance against small-scale ordinary fires When a fire extinguishing test is conducted using the following model (Figure 1) in accordance with the provisions of (a) and (b), no residual flames should be observed at the end of the discharge of the extinguishing agent, and no re-ignition should occur within two minutes after the end of the discharge of the extinguishing agent. (i) Pour 0.3 liters of n-heptane (limited to n-heptane with a boiling point between 96 and 102 degrees Celsius and a purity of 95 percent or more; the same applies hereinafter) into the combustion pot and ignite it. (b) Extinguishing the fire should begin three minutes after ignition.

[0026] Next, the modifications made to the standards and regulations in this invention, and the reasons for those modifications, will be described.

[0027] [Modification 1] model structure Similar to the standards ordinance, the wood used for the model was cedar (35 mm long x 30 mm wide x 450 mm long). In the case of the model specified in the standards ordinance, as shown in Figure 1, each tier has 8 layers with 4 pieces → 4 pieces → 5 pieces → 5 pieces → 4 pieces → 4 pieces → 5 pieces → 5 pieces from top to bottom. However, this method using the model does not allow for a quantitative evaluation of the fire extinguishing capacity of the fire extinguishing equipment. Therefore, the number of layers was made adjustable. In addition, to keep the change in surface area constant when increasing or decreasing the number of layers, the number of pieces arranged in each tier was standardized to 4 or 5.

[0028] The structural details are shown in Figure 2. Hereafter, a model with four bars arranged in a row will be referred to as the "Type-I model" as a fire model, and a model with five bars arranged in a row will be referred to as the "Type-II model" as a fire model.

[0029] In the Type-I model, the spacing between timbers of the same number of rows is 110 mm, while in the Type-II model it is 75 mm (Figure 2). During firefighting, it is foreseeable that differences in the optimal model structure (a difference between 4 or 5 timbers per row) will occur depending on the shape of the sample and the properties of the chemical agent. Therefore, in this invention, both the Type-I and Type-II models will be used as fire models.

[0030] [Modification 2] Fire extinguishing method In this invention, in order to eliminate human influence during firefighting activities (and to make the firefighting test method highly reproducible), the test is to be carried out mechanically using a device. Furthermore, in order to achieve the best performance for each throwable simple fire extinguishing tool, it was necessary to evenly distribute the fire extinguishing agent onto the model. Therefore, in this invention, a crushing device 100 as a firefighting test device was developed, as shown in Figures 3, 4-1, and 4-2.

[0031] This smashing device 100 allows the sample to be dropped by the weight of the mounting rod 140, to which the sample is attached at the tip, thereby striking the sample onto the top of the model with minimal force and causing it to break, thus scattering the chemical agent throughout the model.

[0032] In Figures 3, 4-1, and 4-2, the arrows indicated in the drawings are defined as follows: F for forward, B for backward, R for right, L for left, U for up, and D for down.

[0033] The smashing device 100 comprises a main body 110, a mounting rod 140, and a receiving member 130.

[0034] As shown in Figures 3, 4-1, and 4-2, the main body 110 has a flat base plate 112, with elongated flat caster plates 114 attached to the front and rear ends, and two casters 116 attached to the underside of each caster plate 114, for a total of four casters.

[0035] A pair of frames 118, each roughly U-shaped in form by a pair of support columns and connecting columns, are erected from the upper surfaces of the front and rear ends of the base plate 112. A pair of flat support plates 122 are stretched between the frames 118 along the front-to-back direction.

[0036] The support plate 122 has four rows of mounting holes 124 that penetrate in the left-right direction and are arranged along the vertical direction. A rectangular spring base 126 is bolted to the rear two rows of mounting holes 124. A receiving member 130 is bolted to the front two rows of mounting holes 124.

[0037] The mounting rod 140 is formed in a rectangular prism shape and is attached to the support plate 122 via a shaft member 142 so as to be rotatable on an axis in the left-right direction. A tension spring 150 is attached to the lower part of the mounting rod 140 and the upper surface of the spring base 126 using a carabiner and eye bolt (not shown). The tension spring 150 biases the mounting rod 140 to tilt forward.

[0038] The mounting rod 140 has through holes 144 formed along the left-right direction, and the cylindrical extraction rod 146 is inserted through the through holes 144 and mounting holes 124, thereby fixing it to the main body 110. Samples 1 and 2 are attached to the mounting rod 140.

[0039] By removing the extraction rod 146, the mounting rod body 140 falls over, and the receiving member 130 sets specimens 1 and 2 to a position 70 ± 2 mm above the fire model (see Figures 4-1 and 4-2).

[0040] [Modification 3] Fire extinguishing start time background In formulating this invention, which was based on the "Ministerial Ordinance Establishing Technical Standards for Aerosol-Type Simple Fire Extinguishing Devices (hereinafter referred to as the Standards Ordinance)" (Ministry of Internal Affairs and Communications Ordinance No. 26 of 2013), the model was modified from that of the Standards Ordinance (see [Modification 1] for the reason).

[0041] Accordingly, while the ministerial ordinance specifies that the fire extinguishing start time is 180 seconds after ignition, given the changes in the size and structure of the model, the fire extinguishing start time should be reconsidered in this invention. In this section, a new fire extinguishing start time was determined based on actual measurement data.

[0042] To make fire extinguishing test methods highly reproducible, simplified, and uniform, it is necessary to standardize the start time of fire extinguishing activities regardless of the height of the tiers or the shape (whether there are 4 or 5 bars per tier). Combustible materials have a phase of combustion called "steady-state combustion."

[0043] In steady-state combustion, the combustion scale of the combustible material remains constant, and the rate of heat generation (the amount of heat generated by the flame, which vaguely refers to energy) is approximated at a constant value (Figure 5). By conducting firefighting activities during the steady-state combustion period, tests can be performed with high reproducibility. Therefore, it is desirable to set the start time of firefighting during steady-state combustion.

[0044] There are no documents that clearly define steady-state combustion, and the definition of steady-state combustion in the field of fire science remains ambiguous. Therefore, the applicant attempted to define steady-state combustion using representative models used in fire extinguishing test methods.

[0045] In past reports evaluating the fire extinguishing performance of sprinklers, when similar models were used, the combustion characteristics were investigated using models with 6, 9, and 12 stages (Sunahara et al. Study on the relationship between the heat generation rate and radiant heat flux of wood cribs burning under water spraying. Journal of the Architectural Institute of Japan, Vol. 75 (2010)). Based on this report, in this experiment, the heat generation rates of 6, 9, and 12 stages were measured for both Type-I and Type-II models.

[0046] Materials and methods (i) Principles This fire extinguishing start time determination test was conducted indoors because it is highly susceptible to airflow. The experiment was also conducted under a 5 m square hood.

[0047] (ii) Testing equipment (ii)-i Combustion Model For the fire extinguishing start time determination test, a model was prepared using Japanese cedar (dimensions per tree: 35 mm long x 30 mm wide x 450 mm long) that had been cured for three days under constant temperature and humidity conditions (20°C, 50% relative humidity).

[0048] As shown in Figure 2, a model with four strings per row was designated as Type-I, and a model with five strings was designated as Type-II. For the experiment, we used Type-I and Type-II models with 6, 9, and 12 rows, respectively.

[0049] (ii)-ii Model installation equipment For setting up the model, a combustion stand 40 made of iron or stainless steel (500 mm long x 500 mm wide x 300 mm high), as shown in Figure 6, was used. Below this combustion stand 40, a combustion pot 30 (450 mm long x 450 mm wide x 50 mm deep), made of the same material as the combustion stand 40, was placed. At this time, the distance between the oil level in the combustion pot 30 and the bottom of the model was set to 240 mm (Figure 7).

[0050] (ii)-iii fuel Regular gasoline was used.

[0051] (iii) Test Procedure (iii)-i Weather conditions during the test The fire extinguishing start time determination test was conducted under the following conditions. - Temperature: 20 ± 10℃ - Fuel temperature: 20 ± 5℃ (iii)-ii Experiment A 30-liter combustion pot was filled with 18.5 mm of water, and 300 ml of fuel was added. The fuel was ignited 20 ± 2 seconds after it was added, and the model was burned until it was extinguished.

[0052] result The heat generation rates for each model are shown in Figure 8, and detailed data is shown in Figure 9. In all models, the heat generation rate reached a temporary peak approximately 60 seconds after fuel ignition and then dropped sharply. After the sharp drop, a period of stabilization in the heat generation rate was observed, and thereafter the heat generation rate decreased (Figure 8).

[0053] Natori et al. (Method for Estimating the Heat Generation Rate Curve of Real Combustible Materials. Journal of Environmental Engineering, Architectural Institute of Japan, No. 161 (2007)) define the steady-state combustion start time as the time when combustion reaches its maximum scale (Figure 5). However, in this experiment, since the model is ignited using fuel, the maximum scale is reached on the heat generation rate graph during fuel combustion (Figures 8 and 9). To eliminate the influence of fuel combustion, in this experiment, the steady-state combustion interval is defined as the period after the fuel has been extinguished.

[0054] Each graph in Figure 8 can be converted into a simpler graph like the one in Figure 10. If the model continues to burn after the fuel has been extinguished, there is a time Tmax in the latter half of the stable period when the heat generation rate is at its maximum (Qmax) (Figure 10). After this Tmax, the heat generation rate enters a decay phase (Figure 10).

[0055] Therefore, this Tmax was defined as the steady-state combustion termination time (Figure 10). The definition of steady-state combustion start time by Natori et al. (2007), "the time when combustion reaches its maximum scale," can be defined as the measurement time of the heat generation rate approximating Qmax in the initial stable period. Therefore, after the fuel has been extinguished and is unaffected by fuel combustion, the value closest to the first measurable Qmax (Qmax ± 10%) was defined as Qx, and that time (Tx) was defined as the steady-state combustion start time (Figure 10).

[0056] In each model, the steady-state combustion termination time Tmax can be determined by identifying Qmax. According to the definition of steady-state combustion in Figure 10, the Qmax for each stage in the Type-I model was as follows: 6 stages: 71.4 kW (Tmax = 412 seconds), 9 stages: 112.6 kW (Tmax = 473 seconds), and 12 stages: 161.0 kW (Tmax = 385 seconds) (Figure 9).

[0057] On the other hand, in the Type-II model, the Qmax for each stage was as follows: 6 stages: 103.8 kW (Tmax = 378 seconds), 9 stages: 168.1 kW (Tmax = 408 seconds), and 12 stages: 241.7 kW (Tmax = 376 seconds) (Figure 9).

[0058] Next, to determine the steady-state combustion start time (Tx), for each model, we found the first heat generation rate Qx and its time Tx that appeared after the fuel ignition subsided, with the value falling within ±10% of the respective Qmax values.

[0059] In the Type-I model, the Tx for each stage was as follows: 6 stages = 121 seconds, 9 stages = 146 seconds, and 12 stages = 157 seconds (Figure 9). In the Type-II model, the Tx for each stage was as follows: 6 stages = 145 seconds, 9 stages = 128 seconds, and 12 stages = 147 seconds (Figure 9).

[0060] So, where in the steady-state combustion phase should the fire extinguishing start time be defined? The "Ministerial Ordinance Establishing Technical Standards for Fire Extinguishers" and the "Ministerial Ordinance Establishing Technical Standards for Aerosol-Type Simple Fire Extinguishers" stipulate that the fire extinguishing start time should be 180 seconds after fuel ignition. In both models, it was confirmed that the steady-state combustion phase was established if the fire extinguishing start time was 150 ± 10 seconds or later.

[0061] In the fire extinguishing start time determination test, the extinguishing time will be 150 ± 10 seconds, not 180 seconds, for the following three reasons: (1) In all six models investigated in the fire extinguishing start time determination test, 150 ± 10 seconds existed in the steady-state combustion section. (2) In all six models investigated in the fire extinguishing start time determination test, the heat generation rate at 150 ± 10 seconds was higher than the heat generation rate at 180 seconds. Therefore, the test will be conducted under more stringent conditions (Figure 11). (3) In the standard ordinance test, the test ends when one model is extinguished. However, in the fire extinguishing start time determination test, the fire extinguishing test is continued by increasing the number of stages once one model is extinguished, so a more efficient test method is required. For this reason, it is desirable for each test to be short.

[0062] [Modification 4] Determining the minimum number of stages in the model background In the heat generation rate measurement experiment, the heat generation rates of 6, 9, and 12 stages of the Type-I and Type-II models were measured, and the steady-state combustion interval was defined based on the results [Modification 3] (hereinafter referred to as this definition). Based on this definition, the steady-state combustion interval and the fire extinguishing start time (150 ± 10 seconds) were determined in the test to determine the minimum number of stages in the model.

[0063] In order to promote the widespread adoption of this invention, a "minimum number of stages" within the testable range should be established as a factor for users to consider when deciding which stage to start testing from. In [Modification 3], representative numbers of stages were selected from Type-I and Type-II models to establish this definition, but it has not been verified how low a number of stages it can be applied to. Therefore, in this section, we attempted to determine the "minimum number of stages" for which testing is possible.

[0064] In [Modification 3], the heat generation rate was quantitatively evaluated using a 5 m square hood and a gas analyzer. However, it was not possible to measure the actual heat generation rate for the low-stage model. Therefore, the heat generation rate was measured using the Heskestad method (Yokoi, 1963; Hasemi et al., 1994; Takase et al., 2020; Tanaka, 2020; Fujimoto et al., 2021), which calculates the heat generation rate from the height of the flame. It should be noted that the high reproducibility of the heat generation rate estimates using this Heskestad method to the actual measured values ​​(analytical method) has been confirmed for the five types of models used in [Modification 3] (only Type-II 12 stages could not be analyzed due to video limitations) (Figure 12). [Test to determine the minimum number of stages in the model] Materials and methods (i) Principles The test to determine the minimum number of stages for the model was conducted indoors because it is highly susceptible to airflow.

[0065] (ii) Testing equipment (ii)-i Combustion Model For the test to determine the minimum number of stages in the model, a model made from dried Japanese cedar (dimensions per piece: 35 mm long x 30 mm wide x 450 mm long) was used.

[0066] As shown in Figure 2, a model with four strings arranged in one row was designated as Type-I, and a model with five strings was designated as Type-II.

[0067] (ii)-ii Model installation equipment For setting up the model, a combustion stand 40 made of iron or stainless steel (500 mm long x 500 mm wide x 300 mm high) as shown in Figure 6 was used. Below this combustion stand 40, a combustion pot 30 (450 mm long x 450 mm wide x 50 mm high) made of the same material as the combustion stand 40 was placed. At this time, the distance between the oil level in the combustion pot 30 and the bottom of the model was set to 240 mm (Figure 7).

[0068] (ii)-iii fuel Regular gasoline was used.

[0069] (iii) Test Procedure (iii)-i Weather conditions during the test The test to determine the minimum number of stages in the model was conducted under the following conditions. - Temperature: 15 ± 5℃ - Fuel temperature: 15 ± 5℃ (iii)-ii Experiment I filled the combustion pot 30 with water to a height of 18.5 mm and added 300 ml of fuel. The model was ignited 20 ± 2 seconds after the fuel was added and allowed to burn until it was extinguished.

[0070] result Figure 13 shows the detailed parameters of each model used in the test to determine the minimum number of stages in the model. When the Type-I model with 5 stages was burned, the fuel extinguished 77 seconds after ignition, and the model extinguished spontaneously in 161 seconds. The extinguishing test requires extinguishing the flame after 150 ± 10 seconds after ignition and confirming re-ignition for 120 seconds; therefore, the model used in the extinguishing test needs to burn for 270 ± 10 seconds or more. Consequently, this model, which extinguished spontaneously in 161 seconds, was concluded to be unsuitable for the test.

[0071] When the Type-II model with 5 stages was burned, a steady-state combustion interval matching this definition was detected. The steady-state combustion started at 132 seconds and ended at 456 seconds, confirming that it is acceptable to start extinguishing at 150 ± 10 seconds (Figure 14). On the other hand, in the case of the 4-stage model, the increasing trend in the rate of heat generation did not end until collapse, and there was no stable interval, so this definition could not be applied (Figure 14).

[0072] Based on the above, we concluded that for the Type-II model, 5 stages are suitable for testing, but 4 stages are unsuitable for testing. Therefore, the minimum number of stages that can be tested for each model is 6 stages for the Type-I model and 5 stages for the Type-II model.

[0073] [Fire extinguishing test method] The following describes the test method for extinguishing ordinary fires with throwable simple fire extinguishers, based on a modified version of the "Ministerial Ordinance Specifying Technical Standards for Aerosol-Type Simple Fire Extinguishers." The fire extinguishing test method flowchart is shown in Figure 15.

[0074] (i) Principles This fire extinguishing test method is highly susceptible to airflow and should not be conducted outdoors. If possible, the work should be carried out under a suitable smoke exhaust hood.

[0075] (ii) Testing equipment (ii)-i Combustion Model This fire extinguishing test method uses a model made from Japanese cedar (dimensions per tree: 35 mm long x 30 mm wide x 450 mm long) that has been cured for three days at a constant temperature and humidity (20°C, 50% relative humidity).

[0076] As shown in Figure 2, models with four items arranged in a row are designated as Type-I models, and models with five items are designated as Type-II models.

[0077] (ii)-ii Model installation equipment For setting up the model, a combustion stand made of iron or stainless steel (500 mm long x 500 mm wide x 300 mm high) as shown in Figure 6 was used. Below this combustion stand, a combustion pot 30 (450 mm long x 450 mm wide x 50 mm deep) made of the same material as the combustion stand was placed. At this time, the distance between the oil level in the combustion pot 30 and the bottom of the model was set to 240 mm (Figure 7).

[0078] (ii)-iii fuel Use regular gasoline or a similar liquid fuel.

[0079] (ii)-iv Firefighting methods The fire will be extinguished using the smashing device described in [Modification 2].

[0080] (iii) Test Procedure (iii)-i Weather conditions during the test This fire extinguishing test method should be carried out under the following conditions. - Temperature: 20 ± 10℃ - Fuel temperature: 20 ± 5℃ - Fire extinguishing fluid temperature: 20 ± 5℃ (iii)-ii Fire extinguishing test Fill the combustion pot 30 with water to a height of 18.5 mm and add 300 ml of fuel. Ignite the fuel 20 ± 2 seconds after filling and allow it to burn for 150 ± 10 seconds. After 150 ± 10 seconds, attempt to extinguish the fire on the model.

[0081] After confirming that the fire is extinguished within 120 seconds of the end of firefighting operations, a 120-second check for re-ignition will be conducted. If no re-ignition is detected within 120 seconds, the firefighting will be considered successful, and the test will be repeated with an increased number of stages in the same model.

[0082] Once the maximum number of fire extinguishing stages is determined, the fire extinguishing areas for Type-I and Type-II are calculated, and the larger value is assigned as the "maximum fire extinguishing area."

[0083] To elaborate, once the maximum number of fire extinguishing stages is determined, the extinguishing area S (cm²) is determined. 2 ) is calculated. The fire extinguishing area S can be found using the following formula. S=αM-2β(M-1) α: Surface area per layer (Type-I model: 2424 cm²) 2 , Type-II model: 3030 cm 2 ) β: Overlap area when raising by one level (Type-I model: 144 cm²) 2 , Type-II model: 225 cm 2 ) M: Number of stages in the model S is calculated for both the Type-I and Type-II models, and the value with the larger number is determined as the "maximum fire extinguishing area" of that fire extinguishing device.

[0084] Test results (Results for products from Fitech Co., Ltd.) (1) Background A fire extinguishing test was conducted on a throwable, simple fire extinguishing device manufactured by FITEC Corporation. The samples used were FITEC throwable fire extinguishing device "Model: FT-01" (hereinafter referred to as Sample 1) and FITEX "Model: FTX-01R" (hereinafter referred to as Sample 2). The appearance of each sample is shown in Figure 16. In addition, to support the academic data during the test, the generated gas was collected in a 5 m square hood and the heat generation rate was quantified using a gas analyzer.

[0085] result The test results are shown in Figure 17.

[0086] Sample 1 extinguished up to 10 levels of the Type-I model (Figure 18A). The extinguishing area was 2.16 m². 2 Furthermore, Sample 1 extinguished up to eight levels of the Type-II model. The extinguishing area in this case was 2.1 m². 2 This is the case (Figure 18A). Therefore, the maximum fire extinguishing area of ​​sample 1 is 2.16 m². 2 It was decided that this would be the case.

[0087] Specimen 2 extinguished the Type-I model up to a maximum of 12 stages (Fig. 18B). The extinguished area at this time was 2.59 m 2 . Also, Specimen 2 extinguished the Type-II model up to a maximum of 10 stages (Fig. 18B). The extinguished area at this time was 2.63 m 2 . Therefore, it was determined that the maximum extinguished area of Specimen 2 was 2.63 m 2 .

[0088] As reference data, the heat release rates at the time of extinguishing failure for each specimen are summarized in Fig. 19.

[0089] The fire extinguishing test method of this embodiment includes a first step of installing a fire model (Type-I model, Type-II model) formed by stacking a plurality of rectangular columnar woods orthogonally in a predetermined manner and igniting the fuel to burn the fire model through the fuel, a second step of colliding a specimen with the upper part of the fire model using a percussion device 100 as a fire extinguishing test device, in which a specimen for throwing filled with a fire extinguishing agent is attached to the container at the start time of the fire extinguishing activity during the steady combustion of the fire model after the fuel is extinguished, a third step of determining whether it is either extinguished or extinguishing failure after a predetermined time has elapsed since the fuel was ignited, a fourth step of repeating the first step, the second step, and the third step, and deriving the maximum extinguished area of the specimen based on the maximum extinguished stages of the fire model, and is performed through these steps.

[0090] According to this, the fire extinguishing performance of each specimen can be correctly evaluated.

[0091] Also, in advance, the first step is performed, the fire model is burned until it is extinguished, the heat release rate of the fire model is measured, for steady combustion, after the fuel is extinguished, in the stable section where the heat release rate is stable, the end point is set as the time point when the heat release rate reaches the maximum value in the second half, and the start point is set as the time point when a value approximating the maximum value in the second half of the heat release rate is first measured, the fire extinguishing activity start time is derived based on the time from the ignition of the fuel.

[0092] According to this method, the start time of firefighting activities in the fire model can be determined by eliminating the influence of the combustion of the fuel used to ignite the fire model.

[0093] Furthermore, the first, second, and third processes are carried out in advance. A minimum stage setting process is performed to derive the minimum number of stages for the fire model based on the rate of heat generation of the fire model and the time elapsed since fuel ignition.

[0094] According to this, the fire model makes it easier to determine which stage to start testing from.

[0095] Furthermore, the fire extinguishing test device of this embodiment is a crushing device 100 used as a fire extinguishing test device in the fire extinguishing test method of the present invention, The main body 110 and A mounting rod 140 is pivotally supported on the main body 110 and to which a specimen can be attached, A receiving member 130 that receives the mounting rod 140, Equipped with, The mounting rod 140 is movable between a collision position where the top of the fire model and the specimen collide, and a standby position where it holds the specimen above the fire model and waits. The mounting rod 140 is equipped with a pull-out rod 146 as a holding means for holding the mounting rod 140 in a standby position, and by releasing the holding state of the holding means, the mounting rod 140 can move from the holding position to the collision position by its own weight.

[0096] According to this method, the fire extinguishing performance of the specimen can be accurately evaluated by keeping the speed, force, etc., of the specimen constant relative to the fire model.

[0097] Furthermore, a tension spring 150 is provided as a biasing member that is stretched between the main body 110 and the mounting rod 140 to assist in moving the mounting rod 140 from its standby position.

[0098] According to this, when the mounting rod 140 is positioned vertically, simply releasing the holding state of the pull-out rod 146, which acts as a holding means, from the standby position may result in the mounting rod 140 not moving. However, by assisting its movement from a stationary state with the tension spring 150, it is possible to prevent the mounting rod 140 from remaining immobile.

[0099] The fire extinguishing test apparatus and fire extinguishing test method of the present invention are not limited to the embodiments described above. That is, various design modifications are possible as long as they do not depart from the spirit of the present invention.

[0100] For example, in the fire extinguishing test method and the fire extinguishing test apparatus, the smashing device can be used as a sample other than samples 1 and 2, which are throwable, simple fire extinguishing tools. [Explanation of Symbols]

[0101] Smashing device 100 Main body 110 Receiving member 130 Mounting rod body 140 Pulling rod 146 150 tension spring Type-I model Type-II model

Claims

1. The first step involves setting up a fire model, which is formed by stacking a predetermined number of rectangular prism-shaped wooden pieces in a predetermined manner, in a predetermined configuration, igniting fuel, and burning the fire model through the fuel, After the fuel has been extinguished, and at the start of firefighting activities during the steady combustion of the fire model, a second step is taken in which a throwable sample, which contains a container filled with fire extinguishing agent, is attached to a fire extinguishing test apparatus and the sample is struck against the upper part of the fire model. A third step involves determining, after a predetermined time has elapsed since the ignition of the fuel, whether the fire has been extinguished or the extinguishing attempt failed. The first, second, and third steps are repeated, and a fourth step is performed to derive the maximum fire extinguishing area of ​​the specimen based on the maximum number of fire extinguishing stages of the fire model. A fire extinguishing test method characterized by being carried out through the following steps.

2. In advance, the first step is performed, the fire model is allowed to burn until it is extinguished, and the rate of heat generation of the fire model is measured. The steady-state combustion described above is defined as ending when the heat generation rate reaches its maximum value in the latter half of the stable section after the fuel has been extinguished, and starting when the first time a value approximating the maximum value in the latter half of the heat generation rate is measured. The fire extinguishing test method according to claim 1, characterized in that the time to start the fire extinguishing activity is derived based on the time from the ignition of the fuel.

3. Prior to this, the first step, the second step, and the third step are performed. The fire extinguishing test method according to claim 1, characterized in that a minimum stage setting step is performed to derive the minimum number of stages of the fire model based on the heat generation rate of the fire model and the time since ignition of the fuel.

4. A fire extinguishing test apparatus used in the fire extinguishing test method according to any one of claims 1, 2, or 3, The main body and A mounting rod that is pivotally supported on the main body and to which the specimen can be attached, A receiving member that receives the aforementioned mounting rod, Equipped with, The mounting rod is movable between a collision position where the upper part of the fire model and the specimen collide, and a standby position where it holds the specimen above the fire model and waits. A fire extinguishing test apparatus characterized by comprising a holding means for holding the mounting rod body in the standby position, wherein the mounting rod body can move from the holding position to the collision position by its own weight by releasing the holding state of the holding means.

5. The fire extinguishing test apparatus according to claim 4, further comprising a biasing member that is stretched between the main body and the mounting rod and assists in moving the mounting rod from the standby position.

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