Flooring material critical radiant flux test flame level spread monitoring method and system

Abstract

The application discloses a floor material critical radiation flux test flame horizontal spread monitoring method and system, and the method comprises the following steps: performing spatial registration on a test box to obtain a flame horizontal propagation distance test calibration image; obtaining a first visible light RGB background image based on a first visible light RGB image of the flame and the flame horizontal propagation distance test calibration image, the first visible light RGB image being an image when a pilot igniter is ignited; obtaining a first infrared image of the test box to obtain a first infrared background image; after igniting a test sample, continuously obtaining test data of a surface of the test sample, identifying whether there is flame based on the test data, the first infrared background image and the first visible light RGB background image, and obtaining a real-time flame position; and obtaining a flame spread distance according to identification results of a plurality of flames and based on a plurality of real-time flame positions.

Description

Technical Field

[0001] This invention belongs to the field of flame horizontal spread monitoring technology, specifically relating to a method and system for monitoring the horizontal spread of flames in a critical radiation flux test of paving materials. Background Technology

[0002] The critical radiative flux of the flooring material was tested according to standard GB / T 11785-2005. During the test, the sample was continuously heated by thermal radiation. Ten minutes before the test, one end of the sample was ignited with an open flame, which was then turned off after 10 minutes. During the test, the testing personnel needed to observe the distance the flame reached on the sample surface through a small window in the test chamber and calculate the critical radiative flux. The test lasted 30 minutes.

[0003] In existing technologies, the testing process requires inspectors to observe the flame spread distance continuously for 30 minutes with the naked eye, which can easily cause visual fatigue and lead to missing the monitoring of the flame spread distance. On the other hand, according to GB / T 11785-2005, the flame spread distance is defined as the farthest distance that a sustained flame can travel along the length of the specimen within a specified time. A sustained flame is defined as a flame that continues to burn for more than 4 seconds on or above the surface of the specimen. However, currently, both visual observation by inspectors and machine vision observation neglect the observation of the flame duration, which can lead to misjudgments of flashover and sustained flame, resulting in significant errors in the test results.

[0004] In addition, the testing personnel need to continuously observe the flame spread of four groups of samples through a small window in the test chamber for approximately 120 minutes during the test. Because the temperature inside the test chamber reaches as high as 150 degrees Celsius and toxic fumes are emitted during the test, the testing environment is extremely unhealthy for the testing personnel. Summary of the Invention

[0005] To overcome the above-mentioned technical defects, the present invention provides a method and system for monitoring the horizontal spread of flames in the critical radiation flux test of paving materials, which can improve the accuracy of flame spread monitoring.

[0006] This invention is achieved through the following scheme:

[0007] A method for monitoring the horizontal spread of flame in a critical radiation flux test of flooring materials, comprising the following steps:

[0008] Spatial registration of the test chamber was performed to obtain a calibration image for the flame horizontal propagation distance test;

[0009] Based on the first visible light RGB image of the flame and the flame horizontal propagation distance test calibration image, a first visible light RGB background image is obtained, wherein the first visible light RGB image is the image when the igniter is ignited;

[0010] Acquire the first infrared image of the sample in the test chamber to obtain the first infrared background image of the sample;

[0011] After the sample is ignited, test data on the sample surface is continuously acquired. Based on the test data, the first infrared background image, and the first visible light RGB background image, the presence of a flame is identified, and the real-time flame position is obtained.

[0012] Based on the identification results of several flames and the real-time flame locations, the flame spread distance is obtained.

[0013] As a further improvement of the present invention, the step of spatially registering the test chamber to obtain a calibration image for the horizontal propagation distance of the flame includes:

[0014] Obtain the thermal radiation flux distribution curve inside the test chamber;

[0015] Obtain a standard board image;

[0016] The calibration image for the flame horizontal propagation distance test is obtained based on the standard plate image.

[0017] As a further improvement of the present invention, the step of obtaining a first visible light RGB background image based on a first visible light RGB image of a flame and a flame horizontal propagation distance test calibration image includes:

[0018] Acquire the first visible light RGB image of the flame;

[0019] Convert the first visible light RGB image to the first Color gamut space;

[0020] Based on the set threshold, generate the first... First binary image in color gamut space;

[0021] A morphological closing operation is performed on the first binary image to obtain the first high-precision flame mask image.

[0022] Based on the flame horizontal propagation distance test calibration image, an affine matrix transformation is performed on the first high-precision flame mask image to obtain the first visible light RGB background image.

[0023] As a further improvement of the present invention, the step of acquiring a first infrared image of the test chamber to obtain a first infrared background image includes:

[0024] Obtain the grayscale-temperature mapping calibration map of the blackbody furnace;

[0025] Acquire the first infrared image;

[0026] Feature extraction is performed on the first infrared image, and combined with the gray-scale-temperature mapping calibration map to remove light and shadow fluctuations, thus obtaining the first infrared feature image of the test chamber environment;

[0027] The first infrared background image is obtained by performing an affine matrix transformation on the first infrared feature image using the flame horizontal propagation distance test calibration image.

[0028] As a further improvement of the present invention, the test data includes: a second visible light RGB image and a second infrared image;

[0029] The step of continuously acquiring test data from the sample surface after ignition, and identifying the presence of a flame based on the test data, a first infrared background image, and a first visible light RGB background image, and obtaining the real-time flame position, includes:

[0030] The second visible light RGB image is compared with the first visible light RGB background image to identify the flame and mark the position of the first flame;

[0031] Acquire the second infrared image;

[0032] The second infrared image is compared with the first infrared background image to identify the flame and mark the location of the second flame.

[0033] The first flame position and the second flame position are weighted and fused to determine whether a flame exists, thus obtaining the real-time flame position.

[0034] As a further improvement of the present invention, the step of comparing the second visible light RGB image with the first visible light RGB background image to identify the flame and mark the position of the first flame includes:

[0035] Convert the second visible light RGB image to the second Color gamut space;

[0036] Based on the set threshold, generate the second... The second binary image in the color gamut space;

[0037] A morphological closing operation is performed on the second binary image to obtain a second high-precision flame mask image.

[0038] Based on the flame horizontal propagation distance test calibration image, an affine matrix transformation is performed on the second high-precision flame mask image to obtain the second visible light RGB background image;

[0039] The second visible light RGB background image is compared with the first visible light RGB background image to identify the flame and mark the position of the first flame.

[0040] As a further improvement of the present invention, the step of comparing the second infrared image with the first infrared background image to identify the flame and mark the position of the second flame includes:

[0041] Feature extraction is performed on the second infrared image, and combined with the gray-scale-temperature mapping calibration map to remove light and shadow fluctuations, thus obtaining the second infrared feature image of the test chamber environment;

[0042] The second infrared background image is obtained by performing an affine matrix transformation on the calibration image of the flame horizontal propagation distance test.

[0043] The first infrared background image is compared with the second infrared background image to identify the flame and mark the location of the second flame.

[0044] As a further improvement of the present invention, if no flame is detected within a set time, the horizontal flame spread distance is output as less than 110 mm.

[0045] As a further improvement of the present invention, the step of obtaining the flame spread distance based on the identification results of several flames and based on several real-time flame positions includes:

[0046] If a flame is detected within a set time period, and the flame is continuously detected between the first and second time periods;

[0047] The flame spread distance is determined based on the relationship between the first flame position and the first position at the second time.

[0048] This invention also provides a system for monitoring the horizontal spread of flames in a critical radiation flux test of paving materials, comprising:

[0049] The test chamber is used to conduct radiation flux tests on samples, and it is equipped with an igniter inside.

[0050] A thermal radiation flux distribution calibration plate is detachably installed inside the test chamber to acquire calibration images for flame horizontal propagation distance testing;

[0051] A visible light camera is fixedly installed on the side of the test chamber to acquire the first visible light RGB image and test data;

[0052] An infrared thermal imager is fixedly installed on the side of the test chamber to acquire the first infrared image and test data;

[0053] An electronic device is connected to the thermal radiation flux distribution calibration plate, the visible light camera, and the infrared thermal imager to receive the flame horizontal propagation distance test calibration image, the first visible light RGB image, the first infrared image, and the test data, thereby realizing the above-mentioned method for monitoring the horizontal spread of flames in the critical radiation flux test of paving materials.

[0054] Compared with the prior art, the beneficial effects of the present invention are: it solves the problems of unstable viewing angle, smoke obstruction and light reflection caused by manual observation in traditional methods, as well as the problem of ignoring the duration of flame on the sample surface. Attached Figure Description

[0055] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, wherein:

[0056] Figure 1 This is a flowchart of the flame horizontal spread monitoring method for the critical radiation flux test of paving materials described in Example 1;

[0057] Figure 2 This is another flowchart of the flame horizontal spread monitoring method for the critical radiation flux test of the paving material described in Example 1;

[0058] Figure 3 This is a schematic diagram of the flame horizontal spread monitoring system for the critical radiation flux test of the paving material described in Example 2.

[0059] Explanation of reference numerals in the attached drawings: 1. Test chamber; 2. Blackbody furnace; 3. Ignition device; 4. Sample; 5. Electronic equipment; 6. Infrared thermal imager; 7. Visible light camera. Detailed Implementation

[0060] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0061] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, the sequence numbers of each step are merely used to distinguish between steps and do not imply that each step must be strictly performed in the order of the numbers.

[0062] Example 1

[0063] This embodiment provides a method for monitoring the horizontal spread of flames in a critical radiation flux test of flooring materials, such as... Figure 1 and Figure 2 As shown, the steps include:

[0064] S1. Spatial registration of the test chamber to obtain a calibration image for the flame horizontal propagation distance test. Specifically, step S1 includes the following steps:

[0065] S11. After the temperature of the test chamber and the temperature of the radiation pyrometer reach the specified conditions, place the thermal radiation flux distribution calibration plate inside the test chamber, calibrate the thermal radiation flux distribution, and output and save the thermal radiation flux distribution curve inside the test chamber.

[0066] S12. Take out the thermal radiation flux distribution calibration plate, put the sample in, and place a 600×600mm checkerboard calibration plate (black and white squares spaced 50mm apart) on the sample surface. Use a visible light camera and an infrared thermal imager to acquire images of the standard plate, including: visible light standard plate image and infrared standard plate image.

[0067] S13. Extract the checkerboard corner points from the standard plate image in step S12 and the high-temperature marker points from the infrared image using computer vision algorithms. Use the improved Hungarian Algorithm to match the two types of feature points, calculate the affine transformation matrix, and output the flame horizontal propagation distance test calibration image of the visible light RGB image and the flame horizontal propagation distance test calibration image of the infrared image.

[0068] S2. Based on the first visible light RGB image of the flame and the flame horizontal propagation distance test calibration image, a first visible light RGB background image is obtained. The first visible light RGB image is the image when the igniter is lit. This is specifically achieved through the following steps:

[0069] S21. Take out the checkerboard calibration plate and acquire the first visible light RGB image of the flame through a visible light camera.

[0070] S22. Perform color gamut conversion and thresholding: Convert the first visible light RGB image to the first... Color gamut space, the first Color gamut space separation brightness and chromaticity / The flames are It exhibits high brightness in space ( Large values) and specific color ranges ( and Concentrated in the orange-red area.

[0071] S23. Based on the set threshold, generate the first... A first binary image in a color gamut space, where white areas are candidate flame pixels, exemplarily, the threshold setting includes: luminance component: (Excluding dark interference), chromaticity components: .

[0072] S24. Morphological Optimization and Noise Filtering: Morphological closing operations are performed on the first binary image, i.e., dilation followed by erosion. Holes within the flame region are filled using a 5×5 elliptical kernel, and the edges are smoothed. Subsequently, through connected component analysis, noise regions with an area less than 100 pixels, such as splashing sparks or reflective points, are removed to obtain the first high-precision flame mask image.

[0073] S25. Based on the flame horizontal propagation distance test calibration image obtained in step S13, perform affine matrix transformation on the first high-precision flame mask image obtained in step S24 to obtain the first visible light RGB background image P0.

[0074] S3. Obtain the first infrared image of the sample in the test chamber to obtain the first infrared background image of the sample. Specifically, step S3 includes the following steps:

[0075] S31. Point the infrared thermal imager at the blackbody furnace, record the grayscale values ​​corresponding to different temperatures, and fit a quadratic curve to obtain the grayscale-temperature mapping calibration map of the blackbody furnace. The calibration temperature range covers 20℃ to 600℃.

[0076] S32. Acquire the first infrared image using an infrared thermal imager.

[0077] S33. Using the Prewitt operator, feature extraction is performed on the first infrared image. Combined with the gray-temperature mapping calibration map, light and shadow fluctuations caused by factors such as material reflection are removed to obtain the first infrared feature image of the test chamber environment.

[0078] S34. Using the flame horizontal propagation distance test calibration image obtained in step S13, perform an affine matrix transformation on the first infrared feature image to obtain the first infrared background image H0.

[0079] S4. After igniting the sample, continuously acquire test data from the sample surface. Based on the test data, the first infrared background image, and the first visible light RGB background image, identify whether a flame exists and obtain the real-time flame position. Two minutes after placing the sample in the test chamber, start igniting the sample and simultaneously activate the visible light camera and infrared thermal imager to continuously capture images of the sample surface, obtaining test data. The test data includes: the second visible light RGB image P at the nth second. n The second infrared image H at the nth second n The position of the first flame at the nth second, PW n The first flame position is the visible light flame tip position PW n The position of the first flame at the nth second, HW n The second flame position is the infrared flame tip position HW. n Step S4 is implemented in the following way:

[0080] S41. Compare the second visible light RGB image Pn with the first visible light RGB background image P0 to identify the flame and mark the position of the first flame.

[0081] In this process, the second visible light RGB image Pn is converted into a second Color gamut space; based on a set threshold, generate a second... A second binary image in the color gamut space is obtained; morphological closing operations are performed on the second binary image to obtain a second high-precision flame mask image; based on the flame horizontal propagation distance test calibration image, an affine matrix transformation is performed on the second high-precision flame mask image to obtain a second visible light RGB background image; the second visible light RGB background image Pn is compared with the first visible light RGB background image P0 to identify the flame and mark the position PW of the first flame. n .

[0082] S42. Acquire the second infrared image H n .

[0083] S43, transfer the second infrared image H n The flame is identified by comparing it with the first infrared background image H0, and the location of the second flame HW is marked. n .

[0084] In this process, the Prewitt operator is used to extract features from the second infrared image, and combined with the gray-scale-temperature mapping calibration map, light and shadow fluctuations are removed to obtain the second infrared feature image of the test chamber environment; the flame horizontal propagation distance test calibration image is used to perform an affine matrix transformation on the second infrared feature image to obtain the second infrared background image H0; the second infrared background image H0 is then processed... n With the second infrared background image H n Perform regional feature and temperature comparison to identify the flame and mark the location of the second flame (HW). n .

[0085] S44. Region-based adaptive weighted fusion: The first flame position Pn and the second flame position PWn are weighted and fused. In high-temperature regions, infrared images are given higher weight (less smoke, more reliable temperature field); in regions with clear edges (high visible light contrast), visible light is given higher weight. Based on the weighted fused image, the presence of a flame on the sample surface and the real-time flame position Pw are finally determined. 1800 .

[0086] S5. Based on the identification results of several flames and the real-time flame positions, obtain the flame spread distance.

[0087] In this embodiment, the entire set time is the time required for the test process. Here, it is assumed that the shooting frequency of the visible light camera and the infrared thermal imager is one image per second, and the set time is selected as 1800 seconds. If a flame is detected within the set time of 1800 seconds, and the flame is continuously detected between the first time n seconds and the second time (n+4) seconds, then the flame spread distance is determined based on the relationship between the first flame position and the first position at the second time.

[0088] Specifically, if both the second visible light RGB image and the second infrared image within the first time period n seconds to the second time period (n+4) seconds indicate a continuous flame, then the PW... n and PW (n+4) Based on the relationship, determine and record the distance the flame travels at time n:

[0089] 1. If PW n ≥PW (n+4) Then the flame spread distance in the nth second is recorded as PW. (n+4) The minimum value is accurate to 50 mm, until n ≤ 1796 s.

[0090] The main purpose here is to verify whether the flame lasts for 4 seconds, so it needs to be compared with images taken in the subsequent 4 seconds.

[0091] 2. If PW n <PW (n+4) Then, the flame spread distance at time n is recorded as PW. n The accuracy is 50mm, and the S4~S5 steps are tested repeatedly until n≤1796.

[0092] If no flame is detected within the set time of 1800 seconds, then repeat steps S41 to S44 until n≤1796, and output that the horizontal spread distance of the flame is less than 110 mm.

[0093] If the second visible light RGB image and the second infrared image within n seconds to (n+4) seconds contain records of flame interruption, record the distance Pw at the time the flame extinguished. x And repeat steps S4 to S5 until n ≤ 1796;

[0094] When n=1796 (i.e., the total monitoring time is 1800 seconds), monitoring ends, and the real-time flame position Pw is output. 1800 The maximum flame spread distance, determined by the visual recognition system using visible light RGB images or videos, is then verified by testing personnel to confirm its validity, and a comprehensive judgment is made regarding the maximum flame spread distance.

[0095] Based on the thermal radiation flux distribution curve in step S11, the maximum flame spread distance Pw is calculated and calibrated. nmax Radiative flux, Pw at the point of flame extinguishing x Radiant flux and real-time flame position Pw 1800 The minimum value of the radiation flux is selected as the critical radiation flux of the sample.

[0096] Example 2

[0097] This embodiment discloses a flame horizontal spread monitoring system for critical radiation flux tests of flooring materials, comprising: a test chamber, a thermal radiation flux distribution calibration plate, a visible light camera, an infrared thermal imager, and electronic equipment. The test chamber is used to conduct radiation flux tests on samples and is equipped with an igniter inside. The thermal radiation flux distribution calibration plate is detachably installed inside the test chamber to acquire calibration images for flame horizontal propagation distance testing. The visible light camera is fixedly installed on the side of the test chamber to acquire a first visible light RGB image and test data. The infrared thermal imager is fixedly installed on the side of the test chamber to acquire a first infrared image and test data. The electronic equipment is connected to the thermal radiation flux distribution calibration plate, the visible light camera, and the infrared thermal imager to receive the flame horizontal propagation distance test calibration image, the first visible light RGB image, the first infrared image, and the test data, thereby realizing the flame horizontal spread monitoring method for critical radiation flux tests of flooring materials in Embodiment 1.

[0098] In practical applications, a monitoring box is installed next to the test chamber to house a visible light camera. Both the visible light camera and the infrared thermal imager are installed at an angle of 30°, 140mm from the sample surface. The visible light camera uses a Sony IMX477 sensor (1080P resolution, 60 frames / second), and the infrared thermal imager uses a FLIR Lepton 3.5 (256×192 resolution, 60 frames / second). A synchronization pulse signal is generated using an FPGA chip, and the timestamps of each frame of the visible light camera and the infrared thermal imager are aligned with an error of less than 0.1ms.

[0099] Based on the above embodiments 1 and 2, the present invention has the following technical effects:

[0100] This invention utilizes dual-modal data fusion and dynamic spatiotemporal registration technology based on visible light and infrared thermal imaging. It employs an improved Hungarian algorithm for feature point matching and utilizes adaptive calibration with a checkerboard calibration plate (registration error <0.5mm) and a grayscale-temperature mapping calibration map to cyclically identify and mark continuous flames. This effectively penetrates smoke interference and eliminates viewing angle deviations. Compared to traditional monocular solutions, the accuracy of flame identification and propagation distance testing is improved by over 45%, solving problems such as missed detections and false detections caused by unstable viewing angles, reflections, and smoke obstruction during manual observation. Furthermore, it strictly adheres to the GB / T 11785-2005 standard for flame duration exceeding 4 seconds, comprehensively judging the propagation distance of continuous flames by cyclically identifying the flame state every 4 seconds, breaking away from the previous approach of only identifying the flame without determining its duration.

[0101] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for monitoring the horizontal spread of flame in a critical radiation flux test of paving materials, characterized in that, Including the following steps: Spatial registration of the test chamber was performed to obtain a calibration image for the flame horizontal propagation distance test; Based on the first visible light RGB image of the flame and the flame horizontal propagation distance test calibration image, a first visible light RGB background image is obtained. The first visible light RGB image is the image when the igniter is ignited. The process includes: acquiring the first visible light RGB image of the flame; converting the first visible light RGB image into a first visible light RGB background image. Color gamut space; based on a set threshold, generate the first... A first binary image in color gamut space; morphological closing operation is performed on the first binary image to obtain a first high-precision flame mask image; based on the flame horizontal propagation distance test calibration image, affine matrix transformation is performed on the first high-precision flame mask image to obtain a first visible light RGB background image; Acquiring a first infrared image of the sample in the test chamber to obtain a first infrared background image of the sample includes: acquiring a grayscale-temperature mapping calibration map of a blackbody furnace; acquiring a first infrared image; extracting features from the first infrared image, combining it with the grayscale-temperature mapping calibration map, removing light and shadow fluctuations, and obtaining a first infrared feature image of the test chamber environment; and performing an affine matrix transformation on the first infrared feature image using a flame horizontal propagation distance test calibration image to obtain a first infrared background image. After igniting the sample, a second visible light RGB image and a second infrared image of the sample surface are continuously acquired. Based on the second visible light RGB image, the second infrared image, the first infrared background image, and the first visible light RGB background image, the presence of a flame is identified, and the real-time flame position is obtained. This includes: comparing the second visible light RGB image with the first visible light RGB background image to identify the flame and mark the first flame position; acquiring the second infrared image; comparing the second infrared image with the first infrared background image to identify the flame and mark the second flame position; and performing weighted fusion of the first flame position and the second flame position to determine whether a flame exists, thus obtaining the real-time flame position. Based on the identification results of several flames and the real-time flame locations, the flame spread distance is obtained.

2. The method for monitoring the horizontal spread of flame in the critical radiation flux test of paving materials according to claim 1, characterized in that, The step of spatially registering the test chamber to obtain a calibration image for the flame horizontal propagation distance test includes: Obtain the thermal radiation flux distribution curve inside the test chamber; Obtain a standard board image; The calibration image for the flame horizontal propagation distance test is obtained based on the standard plate image.

3. The method for monitoring the horizontal spread of flame in the critical radiation flux test of paving materials according to claim 1, characterized in that, The step of comparing the second visible light RGB image with the first visible light RGB background image to identify the flame and mark the position of the first flame includes: Convert the second visible light RGB image to the second Color gamut space; Based on the set threshold, generate the second... The second binary image in the color gamut space; A morphological closing operation is performed on the second binary image to obtain a second high-precision flame mask image. Based on the flame horizontal propagation distance test calibration image, an affine matrix transformation is performed on the second high-precision flame mask image to obtain the second visible light RGB background image; The second visible light RGB background image is compared with the first visible light RGB background image to identify the flame and mark the position of the first flame.

4. The method for monitoring the horizontal spread of flame in the critical radiation flux test of paving materials according to claim 1, characterized in that, The step of comparing the second infrared image with the first infrared background image to identify the flame and mark the location of the second flame includes: Feature extraction is performed on the second infrared image, and combined with the gray-scale-temperature mapping calibration map to remove light and shadow fluctuations, thus obtaining the second infrared feature image of the test chamber environment; The second infrared background image is obtained by performing an affine matrix transformation on the calibration image of the flame horizontal propagation distance test. The first infrared background image is compared with the second infrared background image to identify the flame and mark the location of the second flame.

5. The method for monitoring the horizontal spread of flame in the critical radiation flux test of paving materials according to any one of claims 1 to 4, characterized in that, If no flame is detected within the set time, the horizontal flame spread distance will be less than 110 mm.

6. The method for monitoring the horizontal spread of flame in the critical radiation flux test of paving materials according to claim 1, characterized in that, The steps for determining the flame spread distance based on the identification results of several flames and several real-time flame locations include: If a flame is detected within a set time period, and the flame is continuously detected between the first and second time periods; The flame spread distance is determined based on the relationship between the first flame position and the first position at the second time.

7. A flame horizontal spread monitoring system for critical radiation flux tests of flooring materials, characterized in that, include: The test chamber is used to conduct radiation flux tests on samples, and it is equipped with an igniter inside. A thermal radiation flux distribution calibration plate is detachably installed inside the test chamber to acquire calibration images for flame horizontal propagation distance testing; A visible light camera is fixedly installed on the side of the test chamber to acquire the first visible light RGB image and test data; An infrared thermal imager is fixedly installed on the side of the test chamber to acquire the first infrared image and test data; An electronic device, connected to the thermal radiation flux distribution calibration plate, the visible light camera, and the infrared thermal imager, receives the flame horizontal propagation distance test calibration image, the first visible light RGB image, the first infrared image, and the test data, thereby realizing the flame horizontal spread monitoring method for the critical radiation flux test of paving materials as described in any one of claims 1 to 6.

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