Monitoring system, gas leak notification method and program

Abstract

To provide a monitoring system that detects leakage of gas and presents a diffusion range and a concentration of the gas.SOLUTION: A monitoring system includes: sensors that are installed at a plurality of positions in a facility and detect gas; and a server including means for determining the presence or absence of leakage of the gas on the basis of information detected by the sensor, means for, when determining the presence of the gas, generating a dangerous area display image displaying a diffusion map information displaying a diffusion range of the leakage of the gas and a concentration of the gas in the diffusion range so as to being overlapped with a map of the facility, and means for outputting the dangerous area display image.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a monitoring system, a gas leak notification method, and a program. [Background technology]

[0002] A plant is being planned to use large amounts of high-concentration ammonia as fuel. Currently, the Electricity Business Act and the High-Pressure Gas Safety Act require the installation of gas detectors at facilities handling toxic gases such as ammonia for safety reasons. However, the installation of gas detectors on piping is not mandatory. A diffusion simulation of ammonia gas leaking from such a detection system revealed the possibility of high-concentration gas diffusing without being detected by the gas detector. A toxic gas leak could pose health risks to on-site workers and surrounding residents. In such a situation, it is desirable to display the gas diffusion range and issue an alarm. Furthermore, to address a gas leak, on-site workers must take measures such as closing valves or repairing equipment. However, it is desirable to perform such work outside the gas diffusion range, and even if they enter the diffusion range, it is necessary to keep the work as short as possible. To achieve this, it is desirable to display the gas concentration at the leak location and along the route to the leak location. Patent Document 1 discloses a related technology for calculating the diffusion range of gas in the event of a gas leak from a pipeline. However, Patent Document 1 does not disclose a method for indicating the diffusion range or concentration of a gas. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-287665 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a need for technology that not only detects gas leaks but also indicates the diffusion range and concentration of the leaked gas.

[0005] The present disclosure provides a monitoring system, a gas leak notification method, and a program that can solve the above-mentioned problems. [Means for solving the problem]

[0006] The monitoring system of the present disclosure includes sensors that detect gas installed at multiple locations within a facility; a server that includes means for determining whether or not there is a gas leak based on information detected by the sensors; means for generating, when it is determined that there is a gas leak, a danger area display image that displays diffusion map information, which displays the diffusion range of the leaked gas and the concentration of the gas within the diffusion range, superimposed on a diagram of the facility; and means for outputting the danger area display image. The means for generating the danger area display image calculates diffusion map information based on a database that defines the relationship between the gas concentration, the gas leakage flow rate, the wind speed at the facility, the gas diffusion range, and the gas concentration within the diffusion range, or a trained model that has learned the relationship, the gas concentration detected by the sensor, the leakage flow rate, and wind speed data at the facility, and arranges the diffusion map information in all directions in which the gas may diffuse based on wind direction data going back a predetermined time from when it was determined that there was a gas leak, and generates the danger area display image by superimposing all of the arranged diffusion map information on a diagram of the facility.

[0007] The gas leak notification method of the present disclosure includes a step of determining whether or not there is a gas leak based on information detected by gas detection sensors installed at multiple positions within a facility; a step of generating, when it is determined that there is a gas leak, a danger area display image in which diffusion map information displaying the diffusion range of the leaked gas and the concentration of the gas within the diffusion range is superimposed on a diagram of the facility; and a step of outputting the danger area display image. In the step of generating the danger area display image, diffusion map information is calculated based on a database that defines the relationship between the gas concentration, the gas leakage flow rate, the wind speed at the facility, the gas diffusion range, and the gas concentration within the diffusion range, or a trained model that has learned the relationship, the gas concentration detected by the sensor, the leakage flow rate, and wind speed data at the facility, and the diffusion map information is arranged in all directions in which the gas may diffuse based on wind direction data going back a predetermined time from when it was determined that there was a gas leak, and all of the arranged diffusion map information is superimposed on a diagram of the facility to generate the danger area display image.

[0008] The program of the present disclosure includes the steps of: determining whether or not there is a gas leak based on information detected by gas detection sensors installed at multiple locations within a facility; generating a danger area display image in which, when it is determined that there is a gas leak, diffusion map information showing the diffusion range of the leaked gas and the concentration of the gas within the diffusion range is superimposed on a diagram of the facility; and outputting the danger area display image. and in the step of generating the danger area display image, a process of calculating diffusion map information based on a database that defines a relationship between the concentration of the gas, the leakage flow rate of the gas, the wind speed in the facility, the diffusion range of the gas, and the concentration of the gas within the diffusion range, or a trained model that has learned the relationship, the concentration of the gas detected by the sensor, the leakage flow rate, and wind speed data of the facility, arranging the diffusion map information in all directions in which the gas may diffuse based on wind direction data going back a predetermined time from when it was determined that there was a gas leak, and superimposing all of the arranged diffusion map information on a diagram of the facility to generate the danger area display image. Execute the following. [Effects of the Invention]

[0009] The above-described monitoring system, gas leak notification method, and program are capable of detecting a gas leak and presenting the diffusion range and concentration of the leaked gas. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram illustrating an example of a monitoring system according to a first embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of a detection target plant according to the first embodiment. [Figure 3] FIG. 3 is a first diagram showing an example of the gas leak determination process according to the first embodiment. [Figure 4] FIG. 10 is a second diagram showing an example of the gas leak determination process according to the first embodiment. [Figure 5] FIG. 10 is a third diagram showing an example of the gas leak determination process according to the first embodiment. [Figure 6] FIG. 2 is a diagram illustrating an example of a diffusion prediction database according to the first embodiment. [Figure 7] FIG. 2 is a first diagram showing a display example of a diffusion map according to the first embodiment. [Figure 8] FIG. 10 is a diagram showing an example of a diffusion map created based on wind speed and direction for a predetermined period in the past according to the first embodiment; [Figure 9] FIG. 10 is a second diagram showing an example of a display of a diffusion map according to the first embodiment. [Figure 10] FIG. 3 is a diagram illustrating an example of a first aid database according to the first embodiment. [Figure 11] FIG. 4 is a diagram showing an example of a monitoring screen according to the first embodiment. [Figure 12] FIG. 3 is a diagram showing an example of a screen according to the first embodiment. [Figure 13] FIG. 2 is a diagram showing an example of a flow of gas leak detection and handling processes according to the first embodiment. [Figure 14] FIG. 10 is a first diagram illustrating the correction of a diffusion map according to the second embodiment. [Figure 15]FIG. 10 is a second diagram illustrating the correction of the diffusion map according to the second embodiment. [Figure 16] FIG. 10 is a third diagram illustrating the correction of the diffusion map according to the second embodiment. [Figure 17] FIG. 11 is a diagram showing an example of a flow of gas leak detection and handling processes according to the third embodiment. [Figure 18] FIG. 2 is a diagram illustrating an example of a hardware configuration of a monitoring system according to each embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] A monitoring system according to the present disclosure will be described below with reference to FIGS. First Embodiment (System Configuration) 1 is a block diagram showing an example of a monitoring system according to an embodiment. The monitoring system 100 includes sensors 30 for detecting the presence and location of a gas leak, a server 10 for monitoring the information detected by the sensors 30 and detecting and predicting the spread of gas leaks, and a mobile terminal 50 for receiving information on the gas leak location and danger area predicted by the server 10. The monitoring system 100 uses multiple sensors 30 to detect all gas leaks such as ammonia, maps the range of spread and concentration, and promptly notifies on-site workers of the location and content of emergency measures to be taken in response to the gas leak, and notifies nearby residents of evacuation instructions, thereby reducing the risk of personal injury and other damage.

[0012] The monitoring system 100 includes a server 10, a monitor 20, a sensor 30, a mobile terminal 50, and an alarm device 60. The monitoring system 100 may further include a handheld measuring device 40, which is a portable sensor. The server 10, the sensor 30, the handheld measuring device 40, the mobile terminal 50, and the alarm device 60 are communicatively connected via a network NW. The server 10 is installed in a central control room or the like and detects gas leaks based on information detected by the sensor 30, the handheld measuring device 40, etc., and generates a diffusion map showing the gas diffusion range and gas concentration, as well as emergency response guidance information. The monitor 20 displays the diffusion map and emergency response guidance information generated by the server 10. A monitor in the central control room or the like refers to the monitor 20 to confirm that a gas leak has been detected, as well as the diffusion range and concentration of the leaked gas. The sensor 30 is a sensor that detects gas. The gas detected by the sensor 30 is, for example, a toxic gas. Toxic gases are specified by laws and regulations, and include, for example, acrylonitrile, acrolein, sulfur dioxide, arsine, ammonia, carbon monoxide, chlorine, chloromethyl, chloroprene, arsenic pentafluoride, phosphorus pentafluoride, ethylene oxide, nitrogen trifluoride, boron trifluoride, phosphorus trifluoride, hydrogen cyanide, diethylamine, disilane, sulfur tetrafluoride, silicon tetrafluoride, diborane, hydrogen selenide, trimethylamine, carbon disulfide, fluorine, bromomethyl, benzene, phosgene, phosphine, monogermane, monosilane, monomethylamine, hydrogen sulfide, etc. In the following, an example will be described in which the gas to be detected is ammonia, but the type of gas is not limited.

[0013] (gas detection sensor) The sensor 30 is appropriately selected based on the state of the gas (gaseous, liquid, temperature) and rules stipulated by laws and regulations (for example, whether or not a gas detector needs to be installed). The sensor 30 detects the gas concentration, etc. FIG. 2 shows an example of a plant where gas leaks are detected. In the plant 200, ammonia is used as fuel. Liquefied ammonia is supplied to a pipe 201 from a ship 206 carrying the liquefied ammonia and stored in a tank 202. When ammonia is used as fuel, the ammonia in the tank 202 is vaporized in a vaporizer 203 and supplied to a boiler 205 through a pipe 204, where it is used as fuel. For example, if the gas detection targets are outdoor low-temperature piping 201 (liquid, no gas detector installed), around outdoor tank 202 (liquid / gas, gas detector installed), and around the indoor burner of boiler 205 (gas, gas detector installed), an optical fiber temperature sensor 30a is installed on the outdoor low-temperature piping 201, and a gas detection camera 30b or a covered gas detector 30c is installed around the outdoor tank 202 and around the indoor burner (inside the boiler 205). The sensor 30 installed on the premises may consist of multiple types of sensors 30a to 30c, or may consist of only one type. Hereinafter, the optical fiber temperature sensor 30a, gas detection camera 30b, and gas detector 30c may be referred to as sensor 30a, sensor 30b, and sensor 30c, respectively. Furthermore, when it is not necessary to distinguish between the sensors, they may be referred to as sensor 30. A wind direction and anemometer 207 may also be installed on the premises of plant 200. Information on the time series of wind direction and wind speed measured by the wind direction and anemometer 207 is transmitted to the server 10, and is acquired and stored by the server 10. In addition, the pipe 201 is provided with a pressure sensor that measures the pressure of the liquefied ammonia flowing through the pipe 201, and the pressure measured by the pressure sensor is transmitted to the server 10, and is acquired and stored by the server 10.

[0014] The optical fiber temperature sensor 30a is installed on the outer surface (outer surface of the metal jacket) of the pipe 201 and detects a drop in temperature of the metal jacket due to leakage of liquefied ammonia gas, which has a lower temperature than the outside air temperature. If the temperature drop is equal to or greater than a specified value, the server 10 determines that there is a gas leak and identifies the location of the leak (location of the temperature drop).

[0015] Gas detection camera 30b is installed around equipment where gas is supplied and stored, such as tank 202 or boiler 205, and visualizes leaked gas clouds with gas detection camera 30b. When a gas cloud is visualized, server 10 determines that there is a gas leak, identifies the leak location (the origin of the gas cloud), and estimates the gas concentration from the infrared intensity of the camera image. The gas concentration is calculated based on a relational expression (graph) based on test data of the infrared intensity of the camera image.

[0016] The gas detector 30c is generally installed inside a cover that is installed to cover flanges, valves, and other equipment that are generally considered to have a high risk of gas leakage. By covering the flanges, gas leaks from the flanges, etc. can be detected more quickly. The gas detector 30c measures the concentration of the leaked gas. However, the gas detector 30c does not necessarily have to be installed inside the cover.

[0017] The installation positions and number of sensors 30 illustrated in Figure 2 are merely examples and are not limited to these. In order to detect gas leaks quickly and without leaking, it is possible to appropriately arrange the gas detectors 30c closely, arrange the gas detection cameras 30b so that they can see everything, and apply optical fiber temperature sensors 30a along the entire length of gases that can be detected by temperature, such as liquefied ammonia. Furthermore, the optical fiber temperature sensors 30a may be installed in a divided section of the heat insulation material covering the piping 201 to make it easier to obtain information about temperature drops caused by gas leaks.

[0018] The handheld measuring device 40 is carried by a field worker who takes action when a gas leak is detected in the plant 200. The handheld measuring device 40 has a gas detector. The gas detector may be a gas concentration meter or a gas detection camera, and has a function to transmit detection results, etc. The handheld measuring device 40 also has a function to determine its position and, if the gas detector is a gas detection camera, a function to detect the imaging direction of the gas detector. The handheld measuring device 40 transmits the gas detection results (e.g., concentration, camera image) by the gas detector, as well as the position of the handheld measuring device 40 and the imaging direction of the camera to the server 10. Furthermore, if the handheld measuring device 40 has a gas detection camera, the handheld measuring device 40 may also have a function to estimate the concentration from the image captured by the gas detection camera.

[0019] (Notification to on-site workers) The mobile terminal 50 is a smartphone or the like carried by a field worker of the plant 200. The mobile terminal 50 is used by the field worker when evacuating or performing emergency measures. The mobile terminal 50 acquires a diffusion map and guidance information for emergency measures from the server 10 and displays this information. The field worker refers to the displayed information, selects a safe route with a low gas concentration, moves to a work location for emergency measures for the gas leak, and performs emergency measures according to the guidance information. Note that emergency measures also include automatic control of valves and the like. In the case of automatic control, instruction information for emergency measures is notified to a control device for the valves and the like, and the control device identifies the valves and the like that need to be addressed based on the notified instruction information and controls the identified equipment (closing the valves, etc.).

[0020] (Notification to surrounding residents) The alarm device 60 includes, for example, one or more of a speaker, an alarm lamp, a large monitor, etc. If there is a possibility that a gas leak could cause harm to nearby residents, the server 10 transmits information to the alarm device 60 to issue an alarm and urge people to evacuate. Upon receiving information from the server 10, the alarm device 60 outputs audio information informing people that a gas leak has been detected and instructing them to evacuate from dangerous areas or take shelter indoors.

[0021] (Server 10 function) The server 10 includes a diffusion prediction unit 11, an information presentation unit 12, and a communication unit 13. The diffusion prediction unit 11 acquires detection information from the sensor 30 via the communication unit 13, determines whether or not there is a gas leak, and generates a diffusion map and emergency treatment guidance information. The detection information transmitted from the sensor 30 includes identification information of the sensor 30 (in the case of an optical fiber temperature sensor, position information of the optical fiber) and information measured by the sensor 30 (concentration, image, temperature, etc. depending on the type of sensor 30). The diffusion prediction unit 11 also acquires and stores information on the wind direction and wind speed of the plant 200 via the communication unit 13. The wind direction and wind speed information may be measured by the wind direction and wind speed meter 207 of the plant 200 or may be information provided by the Japan Meteorological Agency or the like.

[0022] The diffusion prediction unit 11 includes a location information database 111 , a concentration estimation unit 112 , a diffusion prediction database 113 , and a first aid database 114 . The location information database 111 includes map information of the plant 200. The map information registers latitude and longitude information of each location and identification information of the sensor 30 in association with the installation location of the sensor 30. When the diffusion prediction unit 11 acquires detection information from the sensor 30, it can calculate what information was detected at which location in the plant 200, based on the location information database 111. When the gas concentration or gas leak amount estimated based on the information detected at each location exceeds a predetermined threshold, the diffusion prediction unit 11 determines that a gas leak has occurred in the vicinity of the location where the sensor 30 is installed.

[0023] The concentration estimation unit 112 estimates the gas concentration and the amount of gas leakage based on the values ​​measured by the sensor 30. Next, the process of estimating the gas concentration and the amount of gas leakage and determining whether or not there is a gas leakage will be described with reference to Figures 3 to 5. First, the process of determining whether or not there is a gas leakage will be described with reference to Figure 3.

[0024] FIG. 3 is a first diagram showing an example of the gas leak determination process according to the first embodiment. The diffusion prediction unit 11 acquires and monitors the value (temperature) measured by the sensor 30a via the communication unit 13 (step S1). The diffusion prediction unit 11 determines whether or not there is a temperature drop equal to or greater than a specified value (step S2). If there is no temperature drop equal to or greater than the specified value (step S2; No), the process of step S1 is continued. If there is a temperature drop equal to or greater than the specified value (step S2; Yes), the diffusion prediction unit 11 determines that there is a gas leak. The diffusion prediction unit 11 acquires the leak location and position information (leak location) of the optical fiber in which the temperature drop equal to or greater than the specified value was detected from the detection information (step S3). The diffusion prediction unit 11 determines the latitude and longitude of the leak location based on the location information database 111 and the leak location acquired in step S3 (step S4). In parallel with steps S3 and S4, the concentration estimation unit 112 determines whether or not the pressure measured by a pressure gauge installed in the pipe 201 has decreased by a predetermined value or more (step S5). If the pressure has been reduced by more than the predetermined value (step S5; Yes), the concentration estimation unit 112 estimates the leakage amount based on, for example, a data table showing the relationship between the amount of ammonia leakage and the amount of pressure drop (step S6). If the pressure has not been reduced by more than the predetermined value (step S5; No), the concentration estimation unit 112 assumes the maximum leakage amount at which no pressure drop occurs as the leakage amount based on, for example, a table showing the relationship between the amount of ammonia leakage and the amount of pressure drop (step S7). The diffusion prediction unit 11 acquires information on wind direction and speed (step S8) and performs diffusion prediction (step S9). The diffusion prediction will be described later.

[0025] Next, with reference to FIG. 4, a process for determining whether or not there is a gas leak based on the image captured by the gas detection camera 30b will be described. FIG. 4 is a second diagram illustrating an example of the gas leak determination process according to the first embodiment. The diffusion prediction unit 11 acquires and monitors the video captured by the gas detection camera 30b via the communication unit 13 (step S10). The diffusion prediction unit 11 determines through image processing whether or not a gas cloud is included in the captured video. If a gas cloud is not detected (step S11; No), the process of step S10 continues. If a gas cloud is detected (step S11; Yes), the diffusion prediction unit 11 determines that a gas leak has occurred. The diffusion prediction unit 11 acquires the installation location of the gas detection camera 30b from the detection information, analyzes the position of the object captured by the gas detection camera 30b, and acquires the leak location (step S12). The diffusion prediction unit 11 determines the latitude and longitude of the leak location based on the location information database 111 and the leak location acquired in step S12 (step S13). In parallel with steps S12 and S13, the concentration estimation unit 112 estimates the gas concentration based on the infrared intensity indicated by the color of the gas cloud captured by the gas detection camera 30b (step S14). The diffusion prediction unit 11 acquires information on wind direction and speed (step S15) and performs diffusion prediction (step S16).

[0026] Next, with reference to FIG. 5, a process for determining whether or not there is a gas leak based on the measurement value of the gas detector 30c will be described. FIG. 5 is a third diagram illustrating an example of the gas leak determination process according to the first embodiment. The diffusion prediction unit 11 acquires the gas concentration measured by the covered gas detector 30c via the communication unit 13 and performs monitoring (step S20). The diffusion prediction unit 11 determines whether a concentration equal to or greater than a specified value has been acquired (step S21). If a concentration equal to or greater than the specified value has not been acquired (step S21; No), the process of step S20 continues. If a concentration equal to or greater than the specified value has been acquired (step S21; Yes), the diffusion prediction unit 11 determines that a gas leak has occurred. The diffusion prediction unit 11 acquires the installation location (leak location) and concentration of the gas detector 30c from the detection information (step S22). The diffusion prediction unit 11 determines the latitude and longitude of the leak location based on the location information database 111 and the leak location acquired in step S21 (step S23). The diffusion prediction unit 11 acquires information on wind direction and speed (step S24) and performs diffusion prediction (step S25).

[0027] The location of the leak may be determined by estimating the range based on the concentration at the location where the sensor 30 is installed and the location data of the pipes and tanks where the gas is supplied and stored. For example, if two sensors 30 detect a leak, the diffusion prediction unit 11 may identify the entire range including the two locations where the sensors 30 are installed as the leak location. If the sensor 30 includes a computer, the processes related to concentration estimation in FIGS. 3 and 4 (steps S1 to S2, S5 to S7, S10, S11, and S14) may be performed on the sensor 30 side.

[0028] The diffusion prediction database 113 stores wind speed, the concentration and leakage flow rate of the leaked gas, and a diffusion map illustrating the results of a diffusion simulation (of the leaked gas) calculated under a combination of these conditions, in association with each other. FIG. 6 shows an example of the diffusion prediction database 113. The diffusion prediction database 113 includes a table 113a, a graph 113b, diffusion maps 113c and 113d, etc. Table 113a associates the diffusion map with wind speed, concentration, leakage flow rate, etc. Graph 113b visualizes the relationship between the diffusion map (identifier), wind speed, concentration, and flow rate, among the contents registered in table 113a. The vertical axis of graph 113b represents concentration, the horizontal axis represents flow rate, and lines L1 to L3 representing wind speeds are drawn. For example, point 1 on L1 represents the diffusion map with identifier "1." Diffusion maps 113c and 113d show the diffusion range of the leaked gas and the gas concentration within that diffusion range, with the gas concentration being represented by shades of color. For example, diffusion map 113c illustrates the data for the diffusion range item (2 ppm, 25 ppm, etc.) of the first data in table 113a. The shape of diffusion maps 113c and 113d represents the size and shape of the gas diffusion range, with the gas concentration being represented by shades of color. For example, the concentration is high inside diffusion maps 113c and 113d, and the concentration decreases toward the outside, as represented by shades of color. For example, if the wind speed when a gas leak is detected is A (m / s), the gas concentration estimated by the processing in Figures 3 to 5 is a (ppm), and the leakage flow rate is b (m 3 / s), graph 113b shows that the diffusion range of the gas in this case is indicated by diffusion map 113c with identifier "1." The diffusion prediction unit 11 identifies diffusion map 1 from the wind speed and concentration by referring to table 113a and graph 113b, and adjusts the direction of diffusion map 1 according to the leak location and wind direction. For example, if the leak location is position α of tank 202 in FIG. 2 and the wind direction is northeast, the diffusion prediction unit 11 aligns start point 113c1 of diffusion map 113c with position α of tank 202 and orients end point 113c2 of diffusion map 113c northeast. This makes it possible to calculate the diffusion range and concentration of the gas. FIG. 7 shows an example of a diffusion map whose position and orientation have been adjusted according to the leak location and wind direction, superimposed on map information and satellite images of the plant 200. In this way, by superimposing and displaying the diffusion map 113a obtained based on the wind speed obtained by the wind direction and anemometer, the concentration obtained by the processing of Figures 3 to 5, the leakage flow rate (the leakage flow rate may be analyzed and calculated by a predetermined method, or a predetermined value may be used), and the diffusion prediction database 113 on a satellite photo of the plant 200, it is possible to visually grasp the diffusion range of the leaked gas and the gas concentration at each position within the diffusion range.

[0029] The diffusion prediction database 113 not only stores diffusion simulation results for multiple combinations of flow rate, wind speed, and concentration, but also stores a trained model (relational equation) that has been constructed by learning this data using machine learning or the like and that has learned the relationships between wind speed, concentration, leakage flow rate, and diffusion simulation results (diffusion map). This trained model is constructed so that when wind speed, concentration, and leakage flow rate are input, a diffusion map according to those conditions is output. This trained model makes it possible to calculate a diffusion map for flow rate, wind speed, and concentration in a range where diffusion simulation was not performed.

[0030] In the above description, the direction of the diffusion map is adjusted based on the wind direction information at the time when a gas leak is detected. However, the diffusion prediction unit 11 may calculate the range into which gas may diffuse for greater safety. For example, the diffusion prediction unit 11 may set a predetermined time period prior to the time when the leak signal was obtained by the sensor 30, and set a diffusion map of multiple directions based on the maximum wind speed in each wind direction observed during that period as the danger area. FIG. 8 shows an example of a diffusion map created based on the wind speed and wind direction for a predetermined period prior to the time when the gas leak was detected (e.g., the past 30 minutes). For example, assume that winds were measured in five directions (northwest, west-northwest, west, west-southwest, and southwest) out of 16 directions during the 30 minutes prior to the detection of the gas leak. The diffusion prediction unit 11 identifies diffusion maps 81 to 85 for each of the five directions based on the maximum wind speed in each direction, the concentration and leakage flow rate at the time of gas leak detection, and the diffusion prediction database 113, and adjusts the direction of the diffusion map according to the wind direction. The diffusion prediction unit 11 calculates diffusion maps for multiple directions by matching the starting points of the diffusion maps 81 to 85 to the gas leak location 80. The diffusion prediction unit 11 may also calculate a fan-shaped area as shown in FIG. 9 as the diffusion map 86. The diffusion map 86 in FIG. 9 is obtained by filling in the gaps between the diffusion maps 81 to 85 for multiple directions in FIG. 8. This makes it possible to set a wider range into which toxic gases may reach, and by avoiding this range, safety can be improved.

[0031] The emergency measure database 114 stores information about the installation locations of valves, flanges, and the like of each piece of equipment or its surroundings, and emergency measures to prevent gas leaks when a leak occurs from each piece of equipment or each part (e.g., opening and closing valves, tightening flanges, etc.). FIG. 10 shows an example of the emergency measure database 114. As shown in FIG. 10, the emergency measure database 114 stores information about the equipment at the location where a gas leak is estimated, the devices within the equipment, and the latitude and longitude of the devices, as well as the names of locations where emergency measures should be taken, the latitude and longitude of the locations, and details of the emergency measures, all registered in association with each other. The diffusion prediction unit 11 identifies the location where emergency measures should be taken and the details of the emergency measures based on the latitude and longitude information of the leak location estimated by the processing of FIGS. 3 to 5 and the emergency measure database 114. For example, if the latitude and longitude of the outlet piping of the tank 202 is identified as the leak location, the diffusion prediction unit 11 refers to the emergency treatment database 114 and identifies "shutoff valve A" and "gate valve 1" as emergency treatment locations and "close shutoff valve A" and "open gate valve 1" as emergency treatment details, respectively. The diffusion prediction unit 11 outputs the identified emergency treatment locations and emergency treatment details to the information presentation unit 12. The diffusion prediction unit 11 also outputs information to the information presentation unit 12 recommending evacuation from the facility where a gas leak is suspected or to another safe building, etc. These details are presented to on-site workers as guidance information on emergency treatment methods.

[0032] When the sensor 30 detects information indicating a gas leak, the information presentation unit 12 performs processing to present a screen displaying emergency measures to prevent the leak and the installation locations of valves, flanges, etc. where emergency measures should be taken, along with a map, layout plan, aerial photograph, etc. The information presentation unit 12 includes a sensor information presentation unit 121 and a danger area / emergency measure information presentation unit 122. The sensor information presentation unit 121 generates an image displaying the information detected by the sensor 30 (for example, a display area 91 in FIG. 11 , which will be described next). The danger area / emergency measure information presentation unit 122 generates an image displaying a diffusion map on a satellite photograph of the plant 200, an image displaying guidance information for emergency measures, etc. (for example, display areas 92 and 95 in FIG. 11 ). The information presentation unit 12 generates an image of a monitoring screen including images generated by the sensor information presentation unit 121 and the danger area / first aid information presentation unit 122, and outputs it to the monitor 20 or transmits it to the mobile terminal 50 via the communication unit 13.

[0033] FIG. 11 shows an example of a monitoring screen generated by the information presentation unit 12. The monitoring screen 90 includes a display area 91 displaying optical fiber temperature sensor information, a guidance display area 92, display areas 93 and 94 displaying images of suspected gas leak locations captured by cameras within the facility, a diffusion prediction display area 95, and a tank-surrounding sensor position display area 96. The display area 91 includes a map display area 91a displaying a map of the plant 200 and a temperature status display area 91b displaying the temperature detected by the optical fiber temperature sensors 30a in color. The temperature status display area 91b displays the temperature distribution detected by the optical fiber temperature sensors 30a installed in a range of piping selected by the user on the map displayed in the map display area 91a. By selecting an arbitrary range of piping, the user can check the temperature distribution in the selected range, i.e., whether or not there is a gas leak from the piping. The guidance display area 92 displays the location and content of emergency measures, information recommending evacuation from dangerous areas, and so on. The display area 93 displays an image in which a diffusion map 93a is superimposed on an image taken by a camera (cam1) inside the facility. The display area 94 displays an image in which a diffusion map 94a is superimposed on an image taken by a camera (cam2) inside the facility. The diffusion prediction display area 95 displays an image in which a diffusion map 95a is superimposed on an aerial photograph of the plant 200 or a map of the entire plant 200. The aerial photograph, map, layout plan, overall view, and some other views of the plant 200 are examples of views of the facility (plant 200). The aerial photograph and map in the diffusion prediction display area 95 display the installation locations of valves, flanges, and the like that require emergency repairs. The tank surrounding sensor position display area 96 displays the installation locations of sensors 30 around the tank 202. A monitor in the central control room refers to the monitoring screen 90 displayed on the monitor 20 to understand the status of gas leaks occurring in the plant 200 from various angles.

[0034] The information presenter 12 may generate and transmit to the mobile terminal 50, for example, a screen including only the guidance display area 92 and the diffusion prediction display area 95. Alternatively, the information presenter 12 may generate a screen 97 as shown in FIG. 12 , which depicts a danger area (a diffusion map in multiple directions or a sector-shaped area with gaps filled in), a location of emergency measures, and the details of the emergency measures on an aerial photograph of the plant 200, and transmit the generated screen 97 to the mobile terminal 50. By referring to the transmitted screen 97, a field worker can select a route that avoids the gas diffusion range, head to the shutoff valve A or gate valve 1 where emergency measures should be taken, and take the necessary measures. This makes it possible to stop the gas leak while reducing the risk of health damage to the field worker.

[0035] The communication unit 13 communicates with other devices such as the sensor 30 and the mobile terminal 50. In addition, for example, data on wind direction and wind speed may be received from a server of the Japan Meteorological Agency or the like.

[0036] (Monitoring system operation) Next, with reference to FIG. 13, the flow of processing in which the server 10 generates a monitoring screen and transmits it to the mobile terminal 50 will be described. FIG. 13 is a diagram showing an example of the flow of gas leak detection and handling processing according to the first embodiment. First, the diffusion prediction unit 11 determines whether or not there is a gas leak based on the information detected by the sensor 30 (step S30). This process has been described with reference to FIGS. 3 to 5. If it is determined that there is no leak (step S31; No), the process of step S30 is repeated. If it is determined that there is a leak (step S31; Yes), the diffusion prediction unit 11 acquires wind direction and wind speed data from a predetermined period in the past since the leak was detected (step S32), and identifies a diffusion map by referring to the diffusion prediction database 113 (step S33). The diffusion prediction unit 11 determines the direction of the diffusion map based on the wind direction and outputs the diffusion map (step S34). The diffusion prediction unit 11 may output diffusion maps of multiple directions (risk areas) based on the wind direction and wind speed data from a predetermined period in the past. In parallel with steps S32 to S34, the diffusion prediction unit 11 refers to the emergency treatment database 114 (step S35) and outputs the emergency treatment location and the emergency treatment content according to the leak location (step S36). Next, the information presentation unit 12 generates a screen depicting the danger area, the emergency treatment location, and the emergency treatment content on an aerial photograph (step S37). The information presentation unit 12 transmits the generated screen to the mobile terminal 50 of the field worker via the communication unit 13 (step S38). The field worker approaches the emergency treatment location by moving along a route that allows safe access and performs the emergency treatment (step S39). In addition, the information presentation unit 12 transmits information to the alarm device 60 to guide the worker to evacuate from the dangerous location or to a safe building, etc. The alarm device 60 outputs information guiding the worker to evacuate or take shelter (step S3A).

[0037] (effect) Sensors for detecting gas leaks have been available for some time. However, even if a gas leak can be detected using a sensor alone, the risk of gas diffusion is unknown, potentially exposing workers far from the leak site to potential damage. In contrast, the present embodiment not only detects gas leaks but also presents a diffusion map showing the gas leak range and concentration. Visualizing the risk area associated with a leak using a diffusion map can be useful for ensuring the safety of on-site workers and nearby residents. Furthermore, by registering in advance in a diffusion prediction database the relationships between wind speed, gas concentration, gas flow rate, gas diffusion range, and concentration obtained by interpolating and extrapolating the results of a diffusion simulation or the simulation results using machine learning, the risk area can be instantly calculated when a gas leak is detected.

[0038] In the above embodiment, the mobile terminal 50 is used as a means for notifying the on-site worker, but other means may also be used to notify the indoor worker of the gas leak situation, emergency measures, etc. In this case, the means for notifying the indoor worker is not limited to a mobile terminal, and may be a PC (personal computer) or the like.

[0039] Second Embodiment The images of the danger area described in the first embodiment (FIGS. 8 and 9) take into account wind direction and speed over a predetermined period of time in the past, and set the entire range into which gas could diffuse as the danger area. In this case, there is a possibility that a safe route for on-site workers to reach a location where emergency treatment can be performed will be lost. Therefore, in the second embodiment, the range of the danger area is corrected using information detected not only by the sensor 30 that detected the gas leak, but also by sensors installed in other locations, thereby creating a highly accurate diffusion map or an image of the danger area in which multiple diffusion maps are superimposed.

[0040] For example, if the concentration actually detected by the gas detector 30c at position P1, which is indicated as N1 (ppm) in the diffusion map, is N2 (ppm), which is lower than N1, the diffusion prediction unit 11 corrects the concentration at position P1 to N2 and also corrects the gas concentration in a range outside or downstream of the position P1. The outside range refers to a range on the periphery of the danger zone from the position P1. The downstream range refers to a range farther from the leak location (position P0 in FIG. 14 ) than position P1. For example, if the concentration N2 (ppm) is measured at position P1 in the multiple diffusion maps illustrated in FIG. 8 , a correction may be made to exclude from the danger zone the range of the simulation results (e.g., range H1 in FIG. 14 ) in which the concentration N2 is measured at point P1 on the diffusion map in FIG. 8 .

[0041] 14, if a leak is detected by the gas detector 30c at position P0, but not by the gas detectors 30c at other positions within the danger zone, the diffusion prediction unit 11 may perform a correction to exclude from the danger zone the range downstream of the positions where the other gas detectors 30c are installed. For example, if a leak is not detected by the gas detector 30c at position P1 in FIG. 14, a correction is performed to exclude from the danger zone the range outside line H2 (the range that does not include position P0).

[0042] Furthermore, regarding the identification of the leak location, the method of the first embodiment sets a safe range. However, the range of the leak location may be modified to reflect the concentration or the change in concentration over time measured by one or more gas detectors 30c. For example, if the concentration detected by the gas detector 30c installed at position P2 (FIGS. 15 and 16) is "X1" (ppm), which corresponds to a "small" leak amount, it may be impossible to determine whether the detected "X1" (ppm) is near the leak source (FIG. 15) in the case of a "small" leak amount, or on the periphery (outside) in the case of a "large" leak amount (various cases are possible, as shown in FIG. 16). In such a case, a safer risk area would be set as a wide range that takes all possibilities into account, as shown in FIG. 16. Furthermore, the estimated leak location would be identified as a range including positions P3 and P4. In this case too, if a concentration lower than "X1" (ppm) is detected at any position within the widely defined danger zone, the estimated range of the leak location can be narrowed by reducing or excluding the concentration outside of that detection position according to the detected concentration.

[0043] In the above description, the estimated range of the leak location is corrected based on the concentration detected by the sensor 30 at a certain time. However, the estimated range of the leak location may also be corrected based on the change over time in the detected gas concentration. For example, in the example of Fig. 16, suppose that the gas concentration detected at position P5 at time T1 indicates a gas leak, and that no leak is detected at position P5 at time T2. In this case, the diffusion prediction unit 11 may estimate the range including positions P3 and P4 as the leak location at time T1, and may exclude position P3 from the estimated range of the leak location at time T2.

[0044] While there is no limitation on the type of sensor 30 used to correct the diffusion map and risk area, a gas detection camera 30b, which can detect a wide range of gas concentrations, is more effective than a gas detector 30c, which can only detect a single gas concentration. For example, using a gas detection camera 30b makes it possible to visualize the shape of high-concentration areas, making it easier to estimate the leak location. Even if the leak location is hidden by piping or other obstructions, the leak location can be narrowed to a relatively small area based on the extent of the high-concentration area and the location of the flange or piping that may be leaking. When only data detected by a gas detector 30c is available, the possible range is narrowed based on the diffusion map, the location of the flange or piping that may be leaking, wind speed, and wind direction data. In this case, the estimated leak location range is likely to be wider than with a gas detection camera 30b, so the range is gradually narrowed based on data from multiple sensors and detection results at multiple times.

[0045] (effect) As described above, according to this embodiment, the danger area can be grasped more accurately by correcting the danger area based on the diffusion map based on the detection results of the multiple sensors 30. This allows the field worker to reach the first aid location more safely.

[0046] Third Embodiment In the second embodiment, the risk zone is corrected based on the gas concentration detected by the sensor 30. However, the correction may also be based on the gas concentration detected by the handheld measuring device 40 carried by the field worker. The handheld measuring device 40 includes a gas concentration meter or a gas detection camera, and transmits detected information (concentration and camera footage) and location information of the handheld measuring device 40 to the server 10. In the server 10, for example, the diffusion prediction unit 11 (concentration estimation unit 112) estimates the gas concentration and leak location based on the information detected by the handheld measuring device 40 (FIGS. 4 and 5). Alternatively, the handheld measuring device 40 may have a function for estimating the gas concentration and leak location by the processing of FIGS. 4 and 5. The diffusion prediction unit 11 corrects and improves the accuracy of the estimated range of the risk zone and leak location using the same processing as described in the second embodiment. For example, the diffusion prediction unit 11 corrects and removes from the risk zone the positions where gas is not detected by the handheld measuring device 40 and the range outside those positions. Furthermore, the location of the leak is also limited by excluding from the estimated range the locations where gas is not detected by the handheld measuring device 40 and their vicinity.

[0047] Next, a process flow when a process for correcting a diffusion map based on information detected by the handheld measuring device 40 is incorporated will be described with reference to Fig. 17. The same processes as in Fig. 13 are assigned the same reference numerals and their description will be omitted. First, the diffusion prediction unit 11 determines whether there is a gas leak based on the information detected by the sensor 30 (step S30). If it determines that there is a leak (step S31; Yes), the diffusion prediction unit 11 acquires wind direction and wind speed data (step S32), references the diffusion prediction database 113 (step S33), and outputs a diffusion map (step S34). The diffusion prediction unit 11 also references the emergency measure database 114 (step S35), and outputs the emergency measure location and the emergency measure content (step S36). Next, the information presentation unit 12 generates a screen depicting the danger area, the emergency measure location, and the emergency measure content on the aerial photograph (step S37), and transmits the screen to the mobile terminal 50 (step S38). If the emergency measure location and the route to the emergency measure location are not in a danger area (step S381; No), the field worker travels along a safe approaching route to approach the emergency measure location and perform the emergency measure (step S39). If the emergency treatment location is a danger zone (step S381; Yes), the user approaches the emergency treatment location while detecting the gas concentration using the handheld measuring device 40. The handheld measuring device 40 estimates the gas concentration based on the detected gas concentration and the infrared intensity of the video captured of the surrounding area (step S382). The handheld measuring device 40 transmits the detected or estimated gas concentration and location information to the server 10. In the server 10, the diffusion prediction unit 11 acquires wind direction and wind speed data (step S383) and corrects the diffusion map and danger zone to improve accuracy (step S384). The method of improving accuracy is as described in the second embodiment with reference to FIGS. 14 to 16. Furthermore, for example, if some time has passed since the diffusion map was generated in step S34, the diffusion prediction unit 11 may recalculate the gas diffusion direction based on newly acquired wind direction and wind speed data. The information presenter 12 transmits the improved danger zone to the mobile terminal 50. The field worker, while referring to the corrected danger area, moves along a safe approaching route to the emergency treatment location and performs emergency treatment (step S39). Also, the alarm device 60 outputs information guiding evacuation or evacuation based on instructions from the server 10 (step S3A).

[0048] (effect) As described above, according to this embodiment, the danger area based on the diffusion map is corrected based on the detection results of the handheld measuring device 40. This allows the field worker to accurately grasp the danger area and safely reach the emergency treatment location.

[0049] FIG. 18 is a diagram showing an example of the hardware configuration of a monitoring system according to each embodiment. The computer 900 includes a CPU 901, a main storage device 902, an auxiliary storage device 903, an input / output interface 904, and a communication interface 905. The above-described server 10, sensor 30 (when performing concentration estimation), handheld meter 40 (when performing concentration estimation), and mobile terminal 50 are implemented in the computer 900. The above-described functions are stored in the auxiliary storage device 903 in the form of a program. The CPU 901 reads the program from the auxiliary storage device 903, loads it into the main storage device 902, and executes the above-described processing in accordance with the program. The CPU 901 also allocates a storage area in the main storage device 902 in accordance with the program. The CPU 901 also allocates a storage area in the auxiliary storage device 903 for storing data being processed in accordance with the program.

[0050] A program for implementing all or part of the functions of the server 10, the sensor 30 (if performing concentration estimation), the handheld meter 40 (if performing concentration estimation), and the mobile terminal 50 may be recorded on a computer-readable recording medium, and the program may be loaded into a computer system and executed to perform processing by each functional unit. The term "computer system" as used herein includes hardware such as an OS and peripheral devices. If a WWW system is used, the term "computer system" also includes the homepage provision environment (or display environment). The term "computer-readable recording medium" refers to portable media such as CDs, DVDs, and USBs, as well as storage devices such as hard disks built into the computer system. If the program is distributed to the computer 900 via a communication line, the computer 900 may load the program into the main storage device 902 and execute the processing described above. The program may be for implementing part of the functions described above, or may be capable of implementing the functions described above in combination with a program already stored in the computer system.

[0051] As described above, several embodiments according to the present disclosure have been described, but all of these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents as defined in the claims, as well as in the scope and spirit of the invention.

[0052] <Additional Notes> The monitoring system, gas leak notification method, and program described in each embodiment can be understood, for example, as follows.

[0053] (1) The monitoring system according to the first aspect comprises sensors for detecting gas installed at multiple locations within a facility (plant 200), a means for determining whether or not there is a leak of the gas based on the information detected by the sensors, a server for generating, when it is determined that there is a leak of the gas, a danger area display image (Figures 7, 11, 12) in which diffusion map information showing the diffusion range of the leaked gas and the concentration of the gas within the diffusion range is superimposed on a diagram of the facility (aerial photograph, map, layout diagram, overall view, etc.), and a means for outputting the danger area display image. This makes it possible to detect gas leaks and indicate the diffusion range and concentration of the leaked gas.

[0054] (2) The monitoring system according to the second aspect is the monitoring system of (1), further comprising a terminal device (a mobile terminal 50 or a PC), and the terminal device acquires the danger area display image from the server and displays it. This allows a dangerous area display image (for example, FIGS. 11 and 12) to be displayed on a mobile terminal or the like carried by a field worker.

[0055] (3) A monitoring system according to a third aspect is a monitoring system according to (1) to (2), wherein the server further comprises a means for estimating the location of the gas leakage based on the installation position of the sensor where the gas leakage is detected, a means for determining the location where emergency measures should be taken to stop the gas leakage and the details of the emergency measures based on the leakage location, and a means for outputting an image showing the location where emergency measures should be taken to stop the gas leakage and the details of the emergency measures. This allows the operator to know the emergency measures to stop the gas leak.

[0056] (4) A monitoring system according to a fourth aspect is a monitoring system according to any one of (1) to (3), wherein the means for generating the danger area display image calculates diffusion map information based on a database that defines the relationship between the gas concentration, the gas leakage flow rate, the wind speed in the facility, the gas diffusion range, and the gas concentration within the diffusion range, or a trained model that has learned the relationship, and the gas concentration, leakage flow rate, and wind speed data of the facility that are detected based on the sensor. This allows the diffusion range and concentration of the gas to be calculated.

[0057] (5) A monitoring system according to a fifth aspect is a monitoring system according to any one of (1) to (4), wherein the means for generating the danger area display image arranges diffusion map information in all directions in which the gas may diffuse based on wind direction data going back a predetermined time from when it was determined that there was a gas leak, and generates a danger area display image by superimposing all of the arranged diffusion map information on a diagram of the facility. This makes it possible to indicate the area where gas may leak, which can be useful in ensuring the safety of workers and nearby residents.

[0058] (6) A monitoring system according to a sixth aspect is a monitoring system according to any one of (1) to (5), wherein the means for generating the danger area display image excludes from the diffusion map information a range farther from the gas leakage point in the diffusion map information than the installation position of the sensor when the gas is not detected by the sensor installed within the diffusion range of the gas indicated by the diffusion map information displayed in the danger area display image. This allows the diffusion range and concentration of the gas to be determined with high precision.

[0059] (7) A monitoring system according to a seventh aspect is a monitoring system according to any one of (1) to (6), wherein the means for generating the danger area display image reduces the concentration in a range farther from the gas leakage point in the diffusion map information than the installation position of the sensor when the sensor installed within the diffusion range of the gas indicated by the diffusion map information displayed in the danger area display image detects a concentration lower than the concentration indicated by the diffusion map information. This allows the diffusion range and concentration of the gas to be determined with high precision.

[0060] (8) A gas leak notification method according to an eighth aspect includes the steps of: determining whether or not there is a gas leak based on information detected by gas detection sensors installed at multiple locations within a facility; when it is determined that there is a gas leak, generating a danger area display image in which diffusion map information displaying the diffusion range of the leaked gas and the concentration of the gas within the diffusion range is superimposed on a diagram of the facility; and outputting the danger area display image.

[0061] (9) A program according to a ninth aspect causes a computer to execute the steps of: determining whether or not there is a gas leak based on information detected by gas detection sensors installed at multiple locations within a facility; when it is determined that there is a gas leak, generating a danger area display image in which diffusion map information showing the diffusion range of the leaked gas and the concentration of the gas within the diffusion range is superimposed on a diagram of the facility; and outputting the danger area display image. [Explanation of symbols]

[0062] 10. Server 111···Location Information Database 112...Concentration estimation section 113···Diffusion Prediction Database 114···First Aid Database 12...Information presentation section 121 Sensor information presentation unit 122 Danger Area First Aid Information Display 13. Communications Department 20 Monitor 30 Sensor 30a···Fiber optic temperature sensor 30b Gas detection camera 30c Gas detector 40 Handy measuring instrument 50 Mobile devices 60...Alarm device 100···Monitoring System 900···Computer 901 CPU 902...Main memory 903...Auxiliary storage device 904 Input / Output Interface 905···Communication Interface

Claims

1. sensors for detecting gas installed at multiple locations within the facility; a server including: means for determining whether or not there is a gas leak based on the information detected by the sensor; means for generating, when it is determined that there is a gas leak, a danger area display image in which diffusion map information indicating the diffusion range of the leaked gas and the concentration of the gas within the diffusion range is superimposed on a diagram of the facility; and means for outputting the danger area display image; Equipped with The means for generating the danger area display image includes: Calculating diffusion map information based on a database that defines a relationship between the concentration of the gas, the leakage flow rate of the gas, the wind speed at the facility, the diffusion range of the gas, and the concentration of the gas within the diffusion range, or a trained model that has learned the relationship, the concentration of the gas detected based on the sensor, the leakage flow rate, and wind speed data at the facility, based on wind direction data from a predetermined time back in time after it was determined that there was a gas leak, the diffusion map information is arranged in all directions in which the gas may diffuse, and all of the arranged diffusion map information is superimposed on a diagram of the facility to generate the danger area display image; Monitoring system.

2. a terminal device, the terminal device acquires the danger area display image from the server and displays it. The monitoring system of claim 1 .

3. The means for generating the danger area display image includes: When the gas is not detected by the sensor installed within the gas diffusion range indicated by the diffusion map information displayed on the danger area display image, a range farther from the gas leakage point in the diffusion map information than the installation position of the sensor is excluded from the diffusion map information. The monitoring system according to claim 1 or 2.

4. The means for generating the danger area display image includes: When a concentration lower than the concentration indicated by the diffusion map information is detected by the sensor installed within the diffusion range of the gas indicated by the diffusion map information displayed on the danger area display image, the concentration in a range farther from the gas leakage point in the diffusion map information than the installation position of the sensor is reduced. The monitoring system according to claim 1 or 2.

5. determining whether or not there is a gas leak based on information detected by gas sensors installed at multiple locations within the facility; generating a danger area display image in which, when it is determined that a gas leak has occurred, diffusion map information indicating the diffusion range of the leaked gas and the concentration of the gas within the diffusion range is superimposed on a diagram of the facility; outputting the danger area display image; and In the step of generating the danger area display image, Calculating diffusion map information based on a database that defines a relationship between the concentration of the gas, the leakage flow rate of the gas, the wind speed at the facility, the diffusion range of the gas, and the concentration of the gas within the diffusion range, or a trained model that has learned the relationship, the concentration of the gas detected based on the sensor, the leakage flow rate, and wind speed data at the facility, based on wind direction data from a predetermined time back in time after it was determined that there was a gas leak, the diffusion map information is arranged in all directions in which the gas may diffuse, and all of the arranged diffusion map information is superimposed on a diagram of the facility to generate the danger area display image; Gas leak notification methods.

6. On the computer, determining whether or not there is a gas leak based on information detected by gas sensors installed at multiple locations within the facility; generating a danger area display image in which, when it is determined that a gas leak has occurred, diffusion map information indicating the diffusion range of the leaked gas and the concentration of the gas within the diffusion range is superimposed on a diagram of the facility; outputting the danger area display image; and In the step of generating the danger area display image, Calculating diffusion map information based on a database that defines a relationship between the concentration of the gas, the leakage flow rate of the gas, the wind speed at the facility, the diffusion range of the gas, and the concentration of the gas within the diffusion range, or a trained model that has learned the relationship, the concentration of the gas detected based on the sensor, the leakage flow rate, and wind speed data at the facility, a process of arranging the diffusion map information in all directions in which the gas may diffuse based on wind direction data going back a predetermined time from when it was determined that there was a gas leak, and superimposing all of the arranged diffusion map information on a diagram of the facility to generate the danger area display image; A program that executes the following.

Images