Method for evaluating infection prevention space and infection risk evaluation system

Abstract

In the conventional method, removal or reduction of an infectious substance in a facility or the like in a target space is not considered, and there is room for improvement in evaluation accuracy of an infection risk.SOLUTION: The method for evaluating an infection prevention space includes a setting step, a modeling step, and an evaluation step. In the setting step, building information of the target space SP, facility information of the target space SP, and a model of an infected P1 as an infection source are set. In the modeling step, a distribution state of the aerosol generated from the infection source and the aerosol diffused by the indoor airflow is modeled. In the evaluation step, the infection risk is evaluated based on the modeling result of the modeling step. The modeling includes modeling of an air flow generated by the air conditioner 100 and the ventilation device 200 disposed in the target space SP and modeling related to purification of air before and after passing through the filter 133 of the indoor unit 130 disposed in the target space SP.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This relates to a method for evaluating infection prevention spaces and a system for evaluating infection risks. [Background technology]

[0002] Conventionally, a method has been known in which an analytical model of infection risk is created based on design information of architectural spaces and architectural facilities, and the infection risk is evaluated (Patent Document 1 (JP 2022-182901 A)). Summary of the Invention [Problem to be solved by the invention]

[0003] However, conventional methods do not take into account the removal or reduction of infectious substances in equipment in the target space, and there is room for improvement in the accuracy of infection risk assessment. [Means for solving the problem]

[0004] The first aspect of the method for evaluating an infection prevention space includes a setting step, a modeling step, and an evaluation step. The setting step sets building information for the target space, equipment information for the target space, and a model of a person who is the source of infection. The modeling step models the distribution of aerosols generated from the infection source and aerosols diffused by indoor airflow. The evaluation step evaluates the infection risk based on the modeling results of the modeling step. The modeling includes modeling of airflow generated by an air conditioning device installed in the target space or in a duct through which air flows into or out of the target space, and modeling of air purification before and after passing through a treatment device installed in the target space or duct.

[0005] This method for evaluating infection prevention spaces allows for accurate assessment of infection risk by modeling the distribution of aerosols, taking into account the airflow generated by air conditioning units placed in the target space or duct and the air purification by the treatment unit.

[0006] The second aspect of the method for evaluating an infection prevention space is the method of the first aspect, in which the modeling of air purification involves changing the amount of aerosols passing through the treatment device based on the proportion of aerosols captured when passing through the treatment device.

[0007] This method for evaluating an infection prevention space allows for an accurate evaluation of the infection risk, taking into account the collection of aerosols by the treatment section.

[0008] The method for evaluating an infection prevention space according to the third aspect is the method according to the first or second aspect, in which in the modeling step, the proportion of aerosols that are rendered harmless when passing through the treatment device is specified, and the rendered aerosols are subtracted from the aerosols that pass through the treatment device.

[0009] This method for evaluating an infection prevention space allows for an accurate evaluation of the risk of infection, taking into account the neutralization of aerosols by the treatment unit.

[0010] A method for evaluating an infection prevention space according to a fourth aspect is the method according to any one of the first to third aspects, in which a model of an infected person is set in the setting step, and the infection risk is evaluated based on the number of aerosols that have passed through the infected person in the evaluation step.

[0011] This method for evaluating an infection prevention space makes it possible to evaluate the infection risk of an infected person when inhaling aerosols based on the amount of aerosol inhaled by the infected person.

[0012] A method for evaluating an infection prevention space according to a fifth aspect is the method according to any one of the first to fourth aspects, in which the setting step sets a model of an infected person, and the evaluation step evaluates the infection risk based on two or more types of aerosol diffusion behavior characteristics that differ depending on particle size.

[0013] This method for evaluating infection prevention spaces can evaluate the risk of infection by taking into account the settling of aerosols, even if the aerosols have different particle sizes and contain particles that do not settle and particles that do settle.

[0014] The method for evaluating an infection prevention space of the sixth aspect is the method of the fourth aspect, in which the aerosol that has passed through an infected person includes aerosol that has passed through a specified box placed in the location where the infected person is present.

[0015] This method for evaluating infection prevention spaces involves obtaining the number of aerosols that pass through a box placed in the location of an infected person, thereby determining the amount of aerosols inhaled by the infected person and assessing the risk of infection.

[0016] The infection risk assessment system of the seventh aspect includes a control unit. The control unit receives, as settings, building information for the target space, equipment information for the target space, and a model of a person who is the source of infection. The control unit models the distribution of aerosols in the target space based on the airflow conditions generated by an air conditioning unit installed in the target space or in a duct through which air flows into or out of the target space, and the purification conditions of the air before and after passing through a treatment unit installed in the target space or in the duct. The control unit evaluates the infection risk based on the modeled results of the aerosol distribution conditions.

[0017] This infection risk assessment system can accurately assess infection risk by creating a distribution model of aerosols containing pathogens, taking into account the reduction of aerosols by treatment devices installed in the target space or duct. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic diagram illustrating the configuration of an infection risk assessment system. [Figure 2] FIG. 1 is a diagram illustrating an example of a building to which an infection risk assessment system is applied. [Figure 3] FIG. 2 is a diagram illustrating the air flow in the air conditioner and the ventilation device. [Figure 4] FIG. 10 is a diagram for explaining the processing of aerosols by a processing unit. [Figure 5] FIG. 10 is a diagram showing an example of the aerosol distribution state obtained by the evaluation system. [Figure 6] 10 is a flowchart illustrating an example of processing of the infection risk assessment system. [Figure 7] FIG. 10 is a diagram showing another example of the aerosol distribution state obtained by the evaluation system. [Figure 8] FIG. 10 is a diagram for explaining the processing of aerosols by a processing unit. DETAILED DESCRIPTION OF THE INVENTION

[0019] (1) Overall structure An infection risk assessment system 1 according to an embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of the infection risk assessment system 1. FIG. 2 is an example of a building in which the infection risk is assessed by the infection risk assessment system 1. The infection risk assessment system 1 uses an assessment device 10 to assess the infection risk of a person present in the building H when the person inhales an infectious substance. The infectious substance is, for example, an infectious virus that may be transmitted by aerosol.

[0020] In this embodiment, building H is a hospital. Building H may be, for example, an office building or a commercial facility. Building H, in which an infection risk assessment is performed, has a target space SP, as shown in FIG. 2. Target space SP consists of five rooms, SP1-SP5. Air conditioners 100a-100e and ventilators 200a-200e are installed in target spaces SP1-SP5, respectively. Note that the number and shapes of rooms, and the number and placement of air conditioners and ventilators, are merely examples and do not limit the building to be assessed.

[0021] (2) Detailed configuration (2-1) Air conditioning equipment assumed to be installed in the building to be evaluated Although not limited to this, the infection risk is evaluated by the infection risk evaluation system 1 on the assumption that, for example, an air conditioner 100 and a ventilation device 200 are installed in the building H as air conditioning devices. Note that the air conditioner 100 and the ventilation device 200 do not need to be the same model or have the same capacity, and the infection risk may be evaluated by the infection risk evaluation system 1 on the assumption that they are different models or have different capacities. Furthermore, the evaluation by the evaluation system 1 does not need to assume that both the air conditioner 100 and the ventilation device 200 are installed in the building H, and may assume that only one of them is installed.

[0022] The air conditioner 100 and the ventilation device 200 that are assumed to be installed in the building H will be outlined below.

[0023] (2-1-1) Air conditioner The air conditioner 100 is a device that cools or heats a target space SP using a vapor compression refrigeration cycle. The air conditioner 100 mainly has an indoor unit 130 and an outdoor unit (not shown). The indoor unit 130 is a device that makes up the air conditioning system together with the outdoor unit, which is installed on the roof of or outside the building H.

[0024] 2 and 3 are diagrams for explaining the air flows in the air conditioner 100 and the ventilation device 200. FIG.

[0025] The indoor unit 130 has a heat exchanger 137 that constitutes a refrigeration cycle, an indoor fan 135 that sends indoor air to the heat exchanger 137 and returns it to the target space SP, and so on. The casing of the indoor unit 130 is rectangular in plan view, with an air inlet 131 formed in the center of the bottom surface and air outlets 32 formed along each of the four sides of the bottom surface. Indoor air is drawn in through the air inlet 131 (see arrow Ain in FIG. 3), and the conditioned air is returned to the target space SP through the air outlet 132 (see arrow Aout in FIG. 3).

[0026] In this embodiment, the air conditioner 100 has an air purification function. Specifically, the indoor unit 130 of the air conditioner 100 has a filter 133. The filter 133 is a processing unit that collects aerosols. The aerosols are a mixture of minute particles of infectious substances suspended in the air of the target space SP and the surrounding air.

[0027] 4 is a diagram for explaining the treatment of aerosols by the filter 133. When the air conditioner 100 is operating, air passes through the filter 133 of the indoor unit 130, and the aerosols contained in the air are collected by the filter 133.

[0028] 4, when assessing the risk of infection, it is set that, for example, when the amount of aerosols contained in the air passing through filter 133 is 100%, 90% of the aerosols contained in the air passing through filter 133 adhere to filter 133 and 10% of the aerosols are released into the target space SP. Also, when assessing the risk of infection, it is set that aerosols that have once adhered to filter 133 will not be re-dispersed into the target space SP.

[0029] In assessing the risk of infection, the aerosol collection rate by filter 133 may be set appropriately based on the assumed type of filter 133, the replacement status, etc. Also, instead of assuming that aerosols are not re-emitted, it may be set that a predetermined percentage of aerosols are re-emitted.

[0030] (2-1-2) Ventilation equipment The ventilation device 200 is a ventilation fan having a propeller fan or a sirocco fan. The ventilation device 200 shown in FIG. 3 is installed in a duct 500, draws in indoor air from the target space SP, and discharges it to the outside (outdoor space SO) of the building H. In other words, the ventilation device 200 uses an exhaust fan to draw in indoor air from an air inlet 216 and discharge it from an exhaust outlet 218 to the outdoor space SO. When the ventilation device 200 is operating, the aerosols drawn into the ventilation device 200 are discharged to the outdoor space SO, thereby reducing the amount of aerosols contained in the air in the target space SP.

[0031] (2-2) Evaluation device The evaluation device 10 of the infection risk evaluation system 1 will now be described in detail.

[0032] The evaluation device 10 is a computer and includes a storage unit 20, an input unit 30, a display unit 40, a communication unit 50, and a control unit 60.

[0033] The evaluation device 10 may be a single computer or may be configured with multiple computers. The evaluation system 1 may use a cloud server as the device 10 for various calculations.

[0034] (2-2-1) Storage section The storage unit 20 is a storage device such as a ROM, a RAM, and a hard disk. The storage unit 20 stores programs executed by the control unit 40, data necessary for executing the programs, and the like. In this embodiment, the storage unit 20 stores necessary data such as setting conditions set for the setting unit 61 (described later). The storage unit 20 can be used as a database.

[0035] (2-2-2) Input section The input unit 30 is a keyboard, a mouse, etc. Various information for the evaluation device 10 (various conditions used for modeling and evaluation) is input to the input unit 30.

[0036] (2-2-3) Display section The display unit 40 is a monitor. The display unit 40 can display the results of the infection risk assessment, etc.

[0037] (2-2-4) Communications Department The communication unit 40 is a network interface device for communicating with the air conditioner 100, the ventilation device 200, etc. The communication unit 40 communicates with other devices to receive various types of information from other devices and send various types of information to other devices.

[0038] (2-2-5) Control Unit The control unit 60 includes a control and arithmetic unit (not shown). A processor such as a CPU or a GPU can be used as the control and arithmetic unit. The control and arithmetic unit reads out a program stored in the storage unit 20 and performs predetermined image processing and arithmetic processing in accordance with the program. Furthermore, the control and arithmetic unit can write the results of calculations into the storage unit 20 and read out information stored in the storage unit 20 in accordance with the program.

[0039] As shown in FIG. 1, the control unit 60 functions as a setting unit 61, a generating unit 62, and an evaluating unit 63.

[0040] (2-2-5-1) Setting section The setting unit 61 receives as settings the building information of the target space SP, the facility information of the target space SP, a model of a person who is an infection source, and a model of a person who is infected, which are input from the input unit 30. The various pieces of information received by the setting unit 61 are stored in the memory unit 20.

[0041] The building information includes information regarding the floor plan / drawing of the building H, an air conditioning and ventilation duct route diagram of the building H, and the layout of fixtures in the building H. In this embodiment, the hospital H has target spaces SP1-SP5 partitioned by walls.

[0042] The equipment information includes a list of various information (e.g., equipment type, specifications, installation location, expected operating status, etc.) about the equipment installed in the target space SP (in this embodiment, the target space SP is equipped with an air conditioner 100 and a ventilation device 200 with a purification function), maintenance records (frequency of inspection / cleaning / filter replacement) for the equipment installed in the target space SP, and information about the building equipment, such as the location of air intake and exhaust vents. Note that in this embodiment, the building equipment is assumed to be the air conditioner 100 and the ventilation device 200, but the building equipment may also include air purifiers, dehumidifiers, sterilization devices, lighting, air intake and exhaust vents, fixtures, and various other equipment installed in the building H. Here, the air conditioner 100, ventilation device 200, air purifier, dehumidifier, etc. are air conditioning devices that generate airflow. The air conditioner 100, air purifier, dehumidifier, sterilization device, etc., equipped with an air purification filter, can function as a processing unit in the claims of this application.

[0043] The model of a person (infected person P1), who is the source of infection, is a model of the source of aerosols containing infectious substances. The person model includes the location and number of infected person P1 in the target space SP, the time spent in the target space SP by infected person P1, the exhalation conditions of infected person P1, whether or not infected person P1 is wearing a mask, the type of virus infected person P1, the amount of infectious substance that is the virus infected person P1, and the fever of infected person P1. The exhalation conditions include, for example, information on the amount of air exhaled by a person and whether or not they cough. The person model of infected person P2 includes the location and number of infected person P2 in the target space SP, whether or not infected person P2 is wearing a mask, whether or not infected person P2 has been vaccinated, and the time spent in the target space SP by infected person P2. The exhalation conditions, whether or not they are wearing a mask, the type of virus, and other factors are included here because they affect the concentration distribution of infectious substances in the target space SP and the assessment of infection risk. Other necessary parameters may also be set, such as the operating conditions of equipment such as ventilation systems, air conditioners, air purifiers, dehumidifiers, air cleaners, and sterilizers, one-pass performance, lighting heat output, weather conditions, and the flow rate of infectious substances.

[0044] The setting unit 61 may further receive as settings data from an actual survey of the building H. The actual survey includes measurement data of ventilation airflow, air conditioning airflow, filter collection efficiency, and the like.

[0045] (2-2-5-2) Generation part The generation unit 62 models the distribution of virus-containing aerosols based on the building information of the target space SP, the equipment information of the target space SP, and a model of a person who is an infection source, all of which are stored in the storage unit 20. Specifically, the generation unit 62 models the distribution of virus-containing aerosols in the target space SP based on, for example, the shape of the building in the target space SP, the type and location of fixtures installed in the building, various information about the infected person P1, the location and generated airflow of equipment (such as the air conditioner 100 or the ventilation device 200) installed in the target space SP, the status of air purification before and after passing through the filter 133 of the indoor unit 130, and the like (hereinafter referred to as modeling parameters). The modeling is performed by the control unit 62 of the evaluation device 10, for example, by executing a simulation using thermal fluid analysis software based on the settings of the various modeling parameters. Specifically, the generation unit 62 performs a diffusion simulation of infectious aerosols, airflow analysis, and the like. The airflow analysis includes analysis of air paths, stagnation, and the like.

[0046] The generation unit 62 may perform modeling (simulation) in the target space SP taking into consideration boundary conditions. The setting unit 61 may set boundary conditions of gaps with other rooms in the target space SP, such as undercuts and louvers, and fixtures, as building information. The generation unit 62 may also perform modeling in the target space SP taking into consideration the layout of ducts arranged in the building H.

[0047] (2-2-5-3) Evaluation Section The evaluation unit 63 generates a distribution map of the distribution status of aerosols containing viruses based on the modeling results of the generation unit 62. Furthermore, the evaluation unit 63 calculates the infection probability of infected persons in the target space SP (evaluates the infection risk of infected persons) based on the distribution map of the distribution status of aerosols containing viruses.

[0048] The evaluation unit 63 evaluates the infection risk of an infected person who stays at a certain position in the target space SP for a certain period of time based on the concentration distribution of the infectious substance obtained by the fluid simulation. Specifically, the evaluation unit 63 calculates the amount of aerosol inhaled by the infected person based on the concentration distribution of the infectious substance obtained by the fluid simulation, and evaluates the infection risk based on the calculation result.

[0049] More specifically, the evaluation unit 63, for example, assumes that a predetermined box is placed where the infected person is located and measures the number of aerosols that pass through the box through a simulation to determine the amount of aerosols inhaled by the infected person P2. Note that the amount of aerosol inhaled by the infected person P2 may take into account whether or not the infected person P2 is wearing a mask. The evaluation unit 63 then calculates the infection risk of the infected person P2 based on information on the infection probability for the amount of aerosol inhaled by the infected person P2, which is stored in the memory unit 20. Note that the evaluation of the infection risk of the infected person P2 may take into account whether or not the infected person P2 has been vaccinated. The infection risk may be evaluated numerically or by the level of possibility of infection risk (for example, on a five-point scale).

[0050] As described above, the evaluation unit 63 creates a concentration distribution map of infectious aerosols and calculates the infection probability of infected person P2 present in building H, thereby evaluating which locations within building H have a high risk of infection and how much risk there is of virus infection for infected person P2 present in a specific location within building H.

[0051] Figure 5 shows an example of the distribution of virus-containing aerosols in a target space SP. Here, it is assumed that there is one infected person P1, who is the source of infection, and one infected person P2 in target space SP1 (e.g., an examination room). It is also assumed that there are five infected people P1 and two infected people in target space SP4 (e.g., a hospital reception and waiting room). It is assumed that there are no people in target spaces SP2, SP3, and SP5.

[0052] In Figure 5, the aerosol concentration is shown in four stages: very high concentration, relatively high concentration, medium concentration, and low concentration. For example, as shown in Figure 5, in the target spaces SP1 and SP4, the concentration of aerosols containing viruses is very high at the location where infected person P1 is present (the density of the hatching in Figure 5 represents the concentration of aerosols containing viruses), and the concentration of aerosols containing viruses decreases as the distance from infected person P1 increases. In addition, the concentration of aerosols containing viruses decreases slightly around the air conditioner 100 as a processing unit.

[0053] (3) Processing An example of a processing flow of the infection risk assessment system 1 of this embodiment will be described with reference to the flowchart of FIG.

[0054] In step S1, the setting unit 61 performs a process (referred to as a setting process) of storing information acquired via the input unit 30 and the communication unit 50 in the storage unit 20 as modeling parameters. In the setting process (a process of performing the setting process), the setting unit 61 sets building information of the target space SP, equipment information of the target space SP, and a model of a person (infected person) P1 who is an infection source. In the setting process, the setting unit 61 also sets a model of an infected person P2. For example, the setting unit 61 sets, as building information, information that a hospital H has target spaces SP1-SP5. In addition, the setting unit 61 sets, as equipment information, information that air conditioners 100a-100e and ventilators 200a-200e are installed in the target spaces SP1-SP5, respectively. The setting unit 61 further sets various information such as the positions of the exhaust vents 218a-218e of the target spaces SP1-SP5.

[0055] Furthermore, the setting unit 61 sets a model of people as infected persons and infected individuals, for example, where one infected person P1 exists at a certain position in the target space SP1 and five infected persons P1 exist at certain positions in the target space SP4. Furthermore, the setting unit 61 sets a model of people as infected persons and infected individuals, where one infected person P2 exists at a certain position in the target space SP1 and two infected persons P2 exist at certain positions in the target space SP4.

[0056] In step S2, the generation unit 62 performs processing of a modeling step. In the modeling step, the generation unit 62 models the distribution of aerosols containing viruses in the target space SP based on the modeling parameters described above. In the modeling related to air purification, the generation unit 62 changes the amount of aerosols passing through the filter 130 based on the proportion of aerosols captured when passing through the filter 133 of the indoor unit 130. For example, if the amount of aerosols captured when passing through the filter 133 of the indoor unit 130 is 90%, the generation unit 62 changes the amount of aerosols passing through the filter 133 from 100% to 10% in the modeling related to air purification.

[0057] In step S3, the evaluation unit 63 performs processing for the infection risk evaluation step. In the infection risk evaluation step, the evaluation unit 63 creates a concentration distribution map of aerosols containing viruses based on the modeling results of the modeling step in step S2. In addition, in the infection risk evaluation step, the evaluation unit 63 evaluates the infection risk of an infected person in the target space SP based on the modeling results of the modeling step in step S2. In this embodiment, the evaluation unit 63 evaluates the infection risk based on the number of aerosols that have passed through the infected person P2.

[0058] For example, it is assumed here that there is one infected person P1, who is the source of infection, and one infected person P2 in the target space SP1, and there are five infected people P1 and two infected people in the target space SP4. Therefore, the evaluation unit 63 generates a concentration distribution map of aerosols containing viruses as shown in Figure 5 as the evaluation result.

[0059] Furthermore, the evaluation unit 63 may, for example, calculate the infection risk assessment of the infected person P2 by numerically calculating the infection probability of the infected person P2 present in the target space SP1 to be 1.4%. Furthermore, the evaluation unit 63 may, for example, calculate the infection risk assessment of the infected person P2 by numerically calculating the infection probability of the infected person P2 present in the target space SP4 to be 27.6%. For example, the evaluation unit 63 may evaluate that if the infected person P2 present in the target spaces SP1 and SP4 is wearing a mask, the amount of infectious material inhaled by the infected person P2 is reduced, thereby lowering the infection probability compared to when the infected person P2 is not wearing a mask. Furthermore, the evaluation unit 63 may evaluate that if the infected person P2 present in the target spaces SP1 and SP4 has been vaccinated against a specific infectious virus, the infected person P2's immunity to the specific infectious virus is improved, thereby lowering the infection probability compared to when the infected person P2 has not been vaccinated against the specific infectious virus.

[0060] In step S4, a cluster factor analysis process is performed. In this embodiment, a user of the infection risk assessment system 1 performs the cluster factor analysis process. The process of analyzing the factors of a cluster of infections caused by an infectious substance includes identifying high-risk areas of infection in building H, identifying equipment and air paths that generate airflow, and identifying factors such as stagnant air or insufficient airflow and the diffusion of aerosols.

[0061] In step S5, a solution consideration process is performed. In this embodiment, the user of the infection risk assessment system 1 performs the solution consideration process.

[0062] Solutions are considered from the following perspectives to prevent virus-containing aerosols from reaching the infected person P2. For example, the user considers the layout of equipment in building H that has a cleaning function such as filter collection (equipment that removes infectious aerosols), such as air conditioner 100 with filter 133. The user may also fix the ventilation air volume that dilutes virus-containing aerosols and consider the location of the air intake and exhaust vents in building H. The user may also consider the air intake direction of equipment such as ventilation device 200 and the placement of partitions in target space SP. The user may also consider restoring the functionality of equipment in building H that has deteriorated over time by cleaning and replacing filters. The user may also consider changing the placement of infected person P1 and infected person P2 in building H.

[0063] If a solution has been considered in step S5, it is preferable to execute the processing flow of FIG. 6 again.

[0064] An example of the distribution of virus-containing aerosols in the target space SP after solution consideration in step S5 is shown in Figure 7. For example, since the previous processing flow evaluated that the distribution of aerosols in target spaces SP1 and SP4 was high and the risk of infection was high, the user may assume, as a solution, that air purifiers 300a and 300b, which function as an air conditioner and a processing unit in the claims, are installed in target spaces SP1 and SP4, respectively.

[0065] As a result, for example, as shown in Figure 7, it can be confirmed that in target spaces SP1 and SP4, when air purifiers 300a and 300b are installed, the area with a slightly high aerosol concentration is smaller and the area with a medium aerosol concentration is larger than when air purifiers 300a and 300b are not installed (see Figure 5).

[0066] (4) Features (4-1) The method for evaluating an infection prevention space according to this embodiment includes a setting process, a modeling process, and an evaluation process. The setting process sets building information for the target space SP, equipment information for the target space SP, and a model of an infected person P1, who is the source of infection. The modeling process models the distribution of aerosols generated from the infection source and aerosols diffused by indoor airflow. The evaluation process evaluates the infection risk based on the modeling results of the modeling process. The modeling includes modeling of airflows generated by the air conditioner 100 and ventilation device 200 placed in the target space SP, and modeling of air purification before and after passing through the filter 133 of the indoor unit 130 placed in the target space SP.

[0067] The method for evaluating infection prevention spaces according to this embodiment is effective in, for example, reducing the risk to medical personnel, and enables effective design proposals that focus on facility equipment such as air conditioners and air purifiers.

[0068] Specifically, the infection prevention space evaluation method includes modeling of air purification before and after passing through the filter 133 attached to the indoor unit 130, enabling highly accurate evaluation of infection risk. Furthermore, by using this infection prevention space evaluation method, it is possible to grasp the infection risk reduction effect of using retrofit filters for air conditioners or air purifiers 300, and it is easy to propose improvements that take infection risk into account. Typically, replacing the ventilation device 200 or changing the duct layout requires a lot of work, and the extent of the effect of such work has traditionally depended on the experience of the designer. However, this infection prevention space evaluation method accurately evaluates the infection risk when attaching a filter 133 to the air conditioner 100 or using a portable air purifier 300, making it possible to propose designs that are highly effective in reducing infection risk.

[0069] (4-2) In the method for evaluating an infection prevention space according to this embodiment, the modeling of air purification involves changing the amount of aerosols passing through the filter 133 of the indoor unit 130 based on the ratio of aerosols captured when passing through the filter 133 of the indoor unit 130.

[0070] This method for evaluating an infection prevention space allows for accurate evaluation of the infection risk, taking into account the capture of aerosols by the filter 133 of the indoor unit 130.

[0071] (4-3) In the method for evaluating an infection prevention space according to this embodiment, a model of an infected person P2 is set in the setting step. In the evaluation step, the infection risk is evaluated based on the number of aerosols that have passed through the infected person P2.

[0072] This method for evaluating an infection prevention space makes it possible to evaluate the infection risk of an infected person P2 when they inhale aerosols, based on the amount of aerosols that the infected person P2 inhales.

[0073] (4-4) In the method for evaluating an infection prevention space according to this embodiment, the aerosols that have passed through the infected person P2 include aerosols that have passed through a specified box placed in the location where the infected person P2 is present.

[0074] This method for evaluating infection prevention spaces involves obtaining the number of aerosols that pass through a box placed in the location of the infected person P2, thereby determining the amount of aerosols inhaled by the infected person P2 and assessing the risk of infection.

[0075] (4-5) The infection risk assessment system 1 according to this embodiment includes a control unit 60. A setting unit 61 receives, as settings, building information for the target space SP, equipment information for the target space SP, and a model of an infected person P1 who is the source of infection. A generation unit 62 models the aerosol distribution in the target space SP based on the state of the airflow generated by the air conditioner 100 and ventilation device 200 installed in the target space SP, and the state of air purification before and after passing through the filter 133 of the indoor unit 130 installed in the target space SP. An evaluation unit 63 evaluates the infection risk based on the modeling results of the aerosol distribution.

[0076] In this infection risk assessment system 1, the distribution of aerosols is modeled taking into consideration not only the dilution of aerosols due to ventilation but also the state of air purification due to the capture of aerosols by the filter 133 of the indoor unit 130.

[0077] This infection risk assessment system 1 can accurately assess infection risk by creating a distribution model of aerosols containing pathogens, taking into account the reduction of aerosols by the filter 133 of the indoor unit 130 placed in the target space SP.

[0078] (5) Variations (5-1) Variation 1A The air conditioner 100 may be configured so that the indoor unit 130 is equipped with an ultraviolet device 139, which is an ultraviolet lamp that irradiates ultraviolet light.

[0079] In Modification 1A, the air conditioner 100 is provided with an ultraviolet lamp 139 inside the indoor unit 130. Here, the ultraviolet lamp 139 is arranged downstream of the heat exchanger 137 in the flow of air generated by the indoor fan 135 (see FIG. 3). The ultraviolet lamp 139 is arranged inside the indoor unit 130 in a space where there is no risk of ultraviolet light leaking outside the indoor unit 130. The ultraviolet lamp 139 deactivates infectious substances contained in the air irradiated with ultraviolet light, thereby rendering the aerosol harmless.

[0080] In the modeling process, the generation unit 62 specifies the ratio of aerosols that are rendered harmless when passing through the ultraviolet lamp 139, and performs modeling in which the aerosols that are rendered harmless are subtracted from the aerosols that pass through the ultraviolet lamp 139.

[0081] Fig. 8 is a diagram for explaining an example of processing by the ultraviolet lamp 139. As shown in Fig. 8, for example, if the aerosols contained in the air irradiated with ultraviolet rays by the ultraviolet lamp 139 are taken as 100%, 50% of the aerosols contained in the air irradiated with ultraviolet rays are rendered harmless.

[0082] In the method for evaluating an infection prevention space according to Modification 1A, the risk of infection can be evaluated with high accuracy by taking into consideration the neutralization of aerosols by the ultraviolet lamp 139.

[0083] (5-2) Variation 1B In the evaluation step, the evaluation unit 43 may evaluate the infection risk based on two or more types of diffusion behavior characteristics of the aerosol that differ depending on the particle size. In Modification 1B, in the setting step, the setting unit 61 sets a model of the infected person P2.

[0084] Aerosols include small particles that are difficult to settle and large particles that are easy to settle. In Modification 1B, the evaluation unit 63 takes into account two or more particle sizes of the aerosol. For example, if the aerosol particle size is 0.3 microns, the aerosol will float and will not easily settle to the floor, whereas if the aerosol particle size is 10 microns, the aerosol will easily settle to the floor. The evaluation unit 63 takes into account the settling of aerosols due to different aerosol particle sizes. For example, if the infected person P2 is located far from the infected person P1, aerosols with a particle size of 10 microns exhaled by the infected person P1 will not easily reach the infected person P2, and aerosols with a particle size of 0.3 microns will mainly contribute to infection.

[0085] The evaluation unit 63 evaluates the risk of infection by classifying infectious substances into aerosols with small particle sizes that are less likely to settle and aerosols with large particle sizes that are more likely to settle. The particle sizes may be classified into three or more stages. In evaluating the risk of infection, the evaluation unit 63 calculates the number of infectious substances inhaled for each particle size that takes settling into account.

[0086] In the method for evaluating an infection prevention space of variant example 1B, even if the aerosols have different particle sizes and contain particles that do not settle and particles that do settle, the infection risk can be evaluated by taking into account the settling of the aerosols.

[0087] (5-3) Change Example 1C The evaluation unit 63 may calculate the risk of infection taking into consideration the type of virus that may lead to infection.

[0088] (5-4) Variation 1D In the above embodiment, the air conditioner and processing unit in the claims are described as being installed in the target space SP, but the installation location of the air conditioner and processing unit is not limited to being installed in the target space SP. The air conditioner and processing unit may be arranged in a duct (a duct through which outdoor air or room air passes) through which air flowing into or from the target space SP passes. For example, in the above embodiment, the air conditioner 100 and the air purifier 300 are described as being installed in the target space SP, but the air conditioner 100 and the air purifier 300 may also be installed in a duct. Furthermore, in the above embodiment, the ventilation device 200 is described as being installed in the duct 500, but the ventilation device 200 may also be installed in the target space SP.

[0089] (5-5) Variation 1E In the evaluation using the evaluation system 1, the types of air conditioning devices assumed to be installed in the building H are not limited to the air conditioner 100, ventilation device 200, and air purifier 300 exemplified in the above embodiment, but may be any device that generates air flow in the target space SP. Furthermore, in the evaluation using the evaluation system 1, the number of air conditioning devices assumed to be installed in the building H may be one or more. Furthermore, the type of air conditioning device 100 is not limited to a specific type, and may be an all-in-one air conditioning device, for example, a central air conditioning device.

[0090] (5-6) Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the present disclosure as defined in the claims. [Explanation of symbols]

[0091] 1. Infection risk assessment system 10 Evaluation equipment 20 Memory section 30 Input section 40 Display section 50 Communications Department 60 Control Unit 61 Setting section 62 Generation part 63 Evaluation Department 100 Air conditioners (air conditioning units) 130 Indoor unit 133 Filter (processing section) 135 Indoor fan 137 Heat exchanger 139 Ultraviolet lamp (processing section) 200 Ventilation equipment (air conditioning equipment) 300 Air purifiers (air conditioning equipment, processing units) [Prior art documents] [Patent documents]

[0092] [Patent Document 1] Japanese Patent Publication No. 2022-182901

Claims

1. A setting process for setting building information of a target space (SP), equipment information of the target space, and a model of a person (P1) who is an infection source; a modeling step of modeling the distribution of aerosols generated from the infection source and the aerosols diffused by indoor airflow; an evaluation step of evaluating an infection risk based on the modeling results of the modeling step; Including, The modeling includes modeling of airflow generated by an air conditioning device (100, 200, 300) disposed in the target space or in a duct through which air flows into or flows out of the target space, and modeling of purification of air before and after passing through a treatment device (133, 139) disposed in the target space or the duct. How to evaluate infection prevention spaces.

2. In the modeling of the air purification, the amount of the aerosol passing through the treatment unit is changed based on the ratio of the aerosol collected when passing through the treatment unit. The method for evaluating an infection prevention space according to claim 1.

3. In the modeling step, a proportion of the aerosol that is rendered harmless upon passing through the treatment unit is defined, and the proportion of the aerosol that is rendered harmless is subtracted from the aerosol that passes through the treatment unit. The method for evaluating an infection prevention space according to claim 1 or 2.

4. In the setting step, a model of the infected person (P2) is set, In the evaluation step, the infection risk is evaluated based on the number of aerosols that have passed through the infected person. The method for evaluating an infection prevention space according to claim 1 or 2.

5. In the setting step, a model of an infected person is set, In the evaluation step, the infection risk is evaluated based on two or more types of diffusion behavior characteristics of the aerosol that differ depending on particle size. The method for evaluating an infection prevention space according to claim 1 or 2.

6. The aerosol that has passed through the infected person The aerosol passed through a predetermined box placed in the location of the infected person. The method for evaluating an infection prevention space according to claim 4.

7. A control unit (60) is provided, The control unit Accepting building information of a target space (SP), equipment information of the target space, and a model of a person (P1) who is an infection source as settings; Modeling the distribution of the aerosol in the target space based on the state of the airflow generated by an air conditioning device disposed in the target space or in a duct through which air flows into or flows out of the target space, and the state of purification of the air before and after passing through a treatment device disposed in the target space or in the duct; Evaluating the risk of infection based on the modeling results of the aerosol distribution situation; Infection risk assessment system (1).

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