JP7177457B1 - Aerosol infection risk evaluation method, aerosol infection risk evaluation program, aerosol infection risk evaluation device, air purification system, dust damage risk evaluation method, dust damage risk evaluation program, and dust damage risk evaluation device - Google Patents

Abstract

An object of the present invention is to provide a method for easily evaluating whether there is a risk of aerosol infection in a space having a defined volume. A method for evaluating the risk of aerosol infection according to the present invention includes a releasing step S10 of releasing a plurality of fine particles into a space having a predetermined volume, and after the releasing step S10, releasing the plurality of fine particles in the space. The number of particles is measured multiple times, and the relationship between the elapsed time from the end of the discharging step S10 and the number of the plurality of particles to be measured is specified until the number of particles decreases to a predetermined number. A specifying step S20 of deriving the time and specifying the reduction capability of a plurality of particles in the space from the specific elapsed time; and evaluation steps S30, S34 of assessing that there is a risk of aerosol infection within the body. [Selection drawing] Fig. 31

Description

TECHNICAL FIELD The present invention relates to an aerosol infection risk evaluation method, an aerosol infection risk evaluation program, an aerosol infection risk evaluation device, an air cleaning system, a dust damage risk evaluation method, a dust damage risk evaluation program, and a dust damage risk evaluation device. .

Since 2019, the novel coronavirus disease (COVID-19) has been raging all over the world. Airborne infection is one of the main causes of novel coronavirus infection. Therefore, by avoiding the so-called 3Cs (closed spaces, crowded places, close-contact settings), it is possible to reduce the risk of airborne infections and cluster outbreaks. In other words, avoiding the three Cs is considered to be an effective measure to prevent infection with the novel coronavirus.

The government, related ministries and agencies, local governments, etc. recommend that people do not go in and out of facilities where people gather, such as restaurants, commercial facilities, and entertainment facilities, from the perspective of avoiding the three Cs. In particular, restaurants are confined spaces, and there is a high possibility that people will eat, drink, and talk with their masks off for a long period of time, which increases the risk of airborne infection. As a result, restaurants are forced to shorten their business hours or close their doors, and the number of customers has dropped sharply. However, if it is possible to objectively prove that restaurants can take sufficient measures against the three Cs and that they can be used safely and securely, this kind of situation (shortening of business hours and suspension of business) can be improved. can be one method of

One of the three Cs measures is to thoroughly ventilate the store and remove the virus from the store. Here, conventionally, the ability to remove viruses from inside a specific store has been judged based on the ventilation capacity of the store.

For example, the following four methods are known as methods for measuring the ventilation capacity of a closed space such as a store.
(1) A method of installing an anemometer or the like at the exhaust port of the ventilation system leading to the space to be measured, measuring the air volume at the exhaust port, and calculating the ventilation volume of the space (2) Selecting the space to be measured Method of calculating the ventilation rate of the space by detecting the concentration of _CO2 gas emitted by humans with a sensor, etc. under the ventilation state (3) After filling the space to be measured with tracer gas, ventilation of the space Then, adsorb the tracer gas to the adsorbent installed in the space, quantitatively analyze the quantity of the adsorbed tracer gas, and calculate the ventilation volume of the space from the quantity of the tracer gas (Patent Documents 1 and 2 reference)
(4) After the space to be measured is filled with mist particles, the space is ventilated, and the ventilation amount of the space is calculated from the image data captured by the imaging means installed in the space (Patent Document 3 reference)

Japanese Patent Application Laid-Open No. 2003-42491 JP 2007-10363 JP 2006-250779

By the way, ventilation is a method of discharging virus-contaminated air inside the store to the outside of the store and taking in new air, and it is only one method of reducing the risk of infection. For example, circulating the air in the store with a circulator or air conditioner, using an air purifier, etc. can also reduce the virus concentration and suppress the risk of infection in the store. However, these methods cannot properly evaluate the effects of air circulation and air purifiers.

Specifically, (1) the method using an anemometer or funnel is suitable for evaluating the performance of the store's ventilation system itself, but has the following problems.
(1A) It is not possible to evaluate the ventilation capacity by opening windows and the purification capacity of circulators, air conditioners, air purifiers, etc. (1B) It is troublesome to install an anemometer or funnel at each exhaust port ( 1C) Even if the performance of the ventilation system is evaluated, it is not possible to evaluate the decrease in ventilation efficiency due to the so-called "short circuit." As a result, the fresh air taken in is exhausted without being distributed throughout the room, and conversely, contaminated air that should have been exhausted is re-introduced through the air supply port, resulting in a decrease in ventilation efficiency. That is. When a "short circuit" is formed, the ventilation efficiency is not as high as the value evaluated by the anemometer or funnel, and the virus concentration does not decrease as expected.

In addition, for example, (2) the method of detecting the concentration of CO ₂ gas with a sensor or the like and the method of using a tracer gas have the following problems.
(2A) The diffusion behavior of gaseous CO ₂ gas and tracer gas is different from the diffusion behavior of aerosol-like viruses, and is not suitable for evaluating the risk of aerosol infection (2B) Adsorption by air purifiers, etc.・It is not possible to evaluate the purification ability by dust collection (2C).In particular, the method of detecting the concentration of _CO2 gas, such as using a cassette stove in the audience, generates _CO2 gas other than human breathing. Accurate measurement cannot be performed in the environment (2D) Since the concentration of _CO2 gas emitted by humans is actually measured, the risk of infection cannot be evaluated when the store is closed without customers, and the number of people is smaller than the original capacity. There is a risk of underestimating the infection risk of the space when customers are using it.

Further, for example, (3) the method of photographing mist particles has the following problems.
(3A) The mist particles cannot be photographed as an image unless a considerable amount of mist particles are generated, and this method cannot be said to be a simple method. (3C) If mist particles are used, there is a risk that fire alarms (for example, photoelectric spot detectors, etc.) may react, causing alarm sounds and fire shutters. or fire door closing, etc.

As described above, the method of evaluating the risk of infection based on the ventilation capacity of the store, such as the conventional technology, could not objectively evaluate the risk of infection in the store.

One object of the present invention is to provide a method for easily evaluating whether there is an aerosol infection risk in a space having a defined volume.

The method for evaluating the risk of aerosol infection of the first aspect comprises:
a releasing step of releasing a plurality of microparticles into a space having a defined volume;
After the releasing step, the number of the plurality of fine particles is measured a plurality of times in the space, and the number of the plurality of fine particles is determined based on the relationship between the elapsed time from the end of the releasing step and the number of the measured plurality of fine particles. an identifying step of deriving a specific elapsed time until the quantity of the particles decreases to a predetermined quantity, and identifying the ability to reduce the plurality of particles in the space from the specific elapsed time;
an evaluation step of evaluating that there is an aerosol infection risk in the space when the reduction capability is less than the reduction standard capability required for the space;
including.

The method for evaluating the risk of aerosol infection of the second aspect includes:
In the method for evaluating the risk of aerosol infection of the first aspect,
In the evaluation step, if the performance is equal to or higher than the reduction standard capacity, it is evaluated that there is no aerosol infection risk in the space.

The method for evaluating the risk of aerosol infection of the third aspect includes:
In the method for evaluating the risk of aerosol infection of the first aspect or second aspect,
The reference reduction capacity is the required ventilation capacity required for the volume of the space or the corrected required ventilation capacity obtained by correcting the required ventilation capacity based on the usage mode of at least one or more users who use the space.

The method for evaluating the risk of aerosol infection in the fourth aspect includes:
In the method for evaluating the risk of aerosol infection of the third aspect,
a creating step of creating a report including the reduction capability identified in the identifying step;
further includes

The method for evaluating the risk of aerosol infection of the fifth aspect comprises:
In the method for evaluating the risk of aerosol infection of the fourth aspect,
The creating step creates the report further including information about the two-dimensional spectrum of the relationship.

The method for evaluating the risk of aerosol infection of the sixth aspect comprises:
In the method for evaluating the risk of aerosol infection of the fourth aspect,
When the creating step evaluates that there is an aerosol infection risk in the space, the report includes the lack of the reduction capability required to evaluate that there is no aerosol infection risk in the space. Create a document that further includes information about

The method for evaluating the risk of aerosol infection in the seventh aspect comprises:
In the method for evaluating the risk of aerosol infection of the fourth aspect,
When the creating step evaluates that there is no aerosol infection risk in the space, the extra capacity of the reduction capacity required to evaluate that there is no aerosol infection risk in the space in the report Create a document that further includes information about

In one embodiment, an aerosol infection risk assessment program comprises:
to the computer,
a release function for releasing a plurality of fine particles into a space having a defined volume;
After the emission of the plurality of microparticles is completed, the number of the plurality of microparticles is measured multiple times in the space, and the elapsed time from the termination of the emission of the plurality of microparticles is the measured number of microparticles. A specific function of deriving a specific elapsed time until the quantity of the plurality of particles decreases to a predetermined quantity from the relationship with the quantity, and identifying the ability to reduce the plurality of particles in the space from the specific elapsed time When,
Evaluate that there is an aerosol infection risk in the space when the reduction capacity is less than the reduction standard capacity required for the space, and in the space when the reduction capacity is equal to or higher than the reduction standard capacity an evaluation function that evaluates that there is no aerosol infection risk in
to run.

The aerosol infection risk assessment device of the first aspect includes:
In a space having a predetermined volume, the number of the plurality of microparticles emitted into the space is measured multiple times, and the elapsed time from the end of the emission of the plurality of microparticles is the measured number of microparticles. a specific elapsed time until the quantity of the plurality of particles decreases to a predetermined quantity from the relationship with the quantity, and identifies the reduction capability of the plurality of particles in the space from the specific elapsed time When,
Evaluate that there is an aerosol infection risk in the space when the reduction capacity is less than the reduction standard capacity required for the space, and in the space when the reduction capacity is equal to or higher than the reduction standard capacity an evaluation unit that assesses that there is no risk of aerosol infection in
a control unit that controls the identification unit and the evaluation unit based on the aerosol infection risk evaluation program of the aspect;
Prepare.

The aerosol infection risk assessment device of the second aspect includes:
a release unit disposed in a space having a defined volume for releasing a plurality of microparticles into the space;
The number of the plurality of fine particles is measured multiple times in the space, and the number of the plurality of fine particles is measured based on the relationship between the elapsed time from the end of the emission of the plurality of fine particles by the emitting unit and the number of the measured plurality of fine particles. a specifying unit that derives a specific elapsed time until the number of particles in the space decreases to a predetermined quantity, and specifies the ability to reduce a plurality of particles in the space from the specific elapsed time;
Evaluate that there is an aerosol infection risk in the space when the reduction capacity is less than the reduction standard capacity in the space, and aerosol in the space when the reduction capacity is equal to or higher than the reduction standard capacity An evaluation unit that evaluates that there is no risk of infection,
a control unit that controls the release unit, the identification unit, and the evaluation unit based on the aerosol infection risk evaluation program of the aspect;
Prepare.

The aerosol infection risk evaluation device of the third aspect includes:
In the aerosol infection risk evaluation device of the first aspect or the second aspect,
a creation unit that creates a report of the evaluation result evaluated by the evaluation unit and information accompanying the evaluation result;
Further prepare.

The air cleaning system of the first aspect includes:
the aerosol infection risk assessment device of the second aspect;
A housing having an air inlet and an air outlet, an air blowing source for drawing air into the air inlet and exhausting air from the air outlet, and capturing a plurality of particles sucked from the air inlet together with the air. an air purifying device having a catching portion and being controlled by the control portion to purify the air taken in from the intake port and exhaust the cleaned air from the exhaust port;
with
The air blow source is capable of adjusting the amount of air blown,
When the evaluation unit evaluates that there is a risk of aerosol infection in the space, the control unit or the air cleaning device controls the air blow source to cause the air blow source to blow a large amount of air.

The air cleaning system of the second aspect includes:
In the air cleaning system of the first aspect,
when the evaluation unit evaluates that there is a risk of aerosol infection in the space, a notification unit that notifies the user to that effect;
Further prepare.

The air cleaning system of the third aspect includes:
the aerosol infection risk assessment device of the second aspect;
A housing having an air inlet and an air outlet, an air blowing source for drawing air into the air inlet and exhausting air from the air outlet, and capturing a plurality of particles sucked from the air inlet together with the air. an air purifying device having a catching portion and being controlled by the control portion to purify the air taken in from the intake port and exhaust the cleaned air from the exhaust port;
with
The trapping part can adjust the amount of trapping a plurality of fine particles,
When the evaluation unit evaluates that there is a risk of aerosol infection in the space, the control unit or the air cleaning device controls the trapping unit to trap a large number of the plurality of fine particles in the trapping unit.

The air cleaning system of the fourth aspect includes:
In the air cleaning system of the third aspect,
when the evaluation unit evaluates that there is a risk of aerosol infection in the space, a notification unit that notifies the user to that effect;
Further prepare.

The air cleaning system of the fifth aspect,
In the air cleaning system according to any one of the first to fourth aspects,
The air purifier can humidify and/or adjust the temperature of the air that is taken in through the intake port and exhausted through the exhaust port.

The air cleaning system of the sixth aspect includes:
the aerosol infection risk assessment device of the second aspect;
an exhaust unit that exhausts the air in the space to the outside;
with
The exhaust unit is capable of adjusting the exhaust amount of air,
When the evaluation unit evaluates that there is a risk of aerosol infection in the space, the control unit controls the exhaust unit to cause the exhaust unit to exhaust a large amount of air.

The air cleaning system of the seventh aspect,
In the air cleaning system of the sixth aspect,
when the evaluation unit evaluates that there is a risk of aerosol infection in the space, a notification unit that notifies the user to that effect;
Further prepare.

A method for evaluating dust damage risk in one aspect includes:
a releasing step of releasing a plurality of microparticles into a space having a defined volume;
After the releasing step, the number of the plurality of fine particles is measured a plurality of times in the space, and the number of the plurality of fine particles is determined based on the relationship between the elapsed time from the end of the releasing step and the number of the measured plurality of fine particles. an identifying step of deriving a specific elapsed time until the quantity of the particles decreases to a predetermined quantity, and identifying the ability to reduce the plurality of particles in the space from the specific elapsed time;
an evaluation step of evaluating that there is a dust damage risk in the space when the reduction capacity is less than the reduction standard capacity required for the space;
including.

In one embodiment, a dust damage risk assessment program includes:
to the computer,
a release function for releasing a plurality of fine particles into a space having a defined volume;
After the emission of the plurality of microparticles is completed, the number of the plurality of microparticles is measured multiple times in the space, and the elapsed time from the termination of the emission of the plurality of microparticles is the measured number of microparticles. A specific function of deriving a specific elapsed time until the quantity of the plurality of particles decreases to a predetermined quantity from the relationship with the quantity, and identifying the ability to reduce the plurality of particles in the space from the specific elapsed time When,
Evaluate that there is a risk of dust damage in the space if the reduction capacity is less than the reduction standard capacity required for the space, and if the reduction capacity is equal to or greater than the reduction standard capacity, the space An evaluation function that evaluates that there is no dust damage risk in
to run.

A dust damage risk evaluation device of one aspect includes:
In a space having a predetermined volume, the number of the plurality of microparticles emitted into the space is measured multiple times, and the elapsed time from the end of the emission of the plurality of microparticles is the measured number of microparticles. a specific elapsed time until the quantity of the plurality of particles decreases to a predetermined quantity from the relationship with the quantity, and identifies the reduction capability of the plurality of particles in the space from the specific elapsed time When,
Evaluate that there is a risk of dust damage in the space when the reduction capacity is less than the reduction standard capacity, and evaluate the risk of dust damage in the space when the reduction capacity is equal to or greater than the reduction standard capacity. an evaluation unit that evaluates that there is no
a control unit that controls the identification unit and the evaluation unit based on the dust damage risk evaluation program of the aspect;
Prepare.

The aerosol infection risk evaluation method of the first aspect can easily evaluate whether there is an aerosol infection risk in a space having a defined volume.

The method for evaluating aerosol infection risk of the second aspect can easily evaluate whether or not there is an aerosol infection risk in a space having a defined volume.

The aerosol infection risk assessment method of the third aspect can inform the reduction capability by the generated report.

The method for evaluating the risk of aerosol infection of the fourth aspect visualizes and informs the relationship between the elapsed time from the end of the process of releasing a plurality of microparticles and the number of the plurality of microparticles measured by the generated report. be able to.

The evaluation method of the aerosol infection risk of the fifth aspect can notify the lack of the reduction ability in the space when evaluating that there is an aerosol infection risk in the space.

The method for evaluating the risk of aerosol infection of the sixth aspect can inform the extra capacity of the reduction capacity in the space when evaluating that there is no risk of aerosol infection in the space.

An aerosol infection risk evaluation program of one aspect can cause a computer to easily evaluate whether or not there is an aerosol infection risk in a space having a defined volume.

The aerosol infection risk evaluation apparatuses of the first and second aspects can easily evaluate whether or not there is an aerosol infection risk in a space having a defined volume.

The aerosol infection risk evaluation device of the third aspect can create a report including whether or not there is an aerosol infection risk in a space having a defined volume.

The air purification systems of the first, third, and sixth aspects can automatically reduce the risk of aerosol infection when evaluating that there is a risk of aerosol infection in the space.

The air purification systems of the second, fourth, and seventh aspects can inform the user of the risk of aerosol infection in the space when it is evaluated.

The air cleaning system of the fifth aspect can exhibit one or both of a humidifying function and a temperature adjusting function as well as an air cleaning function that reduces the risk of aerosol infection.

A dust damage risk evaluation method of one aspect can easily evaluate whether there is a dust damage risk in a space having a defined volume.

A program for evaluating dust damage risk according to one aspect can cause a computer to easily evaluate whether or not there is a dust damage risk in a space having a defined volume.

A dust damage risk evaluation device of one aspect can easily evaluate whether or not there is a dust damage risk in a space having a defined volume.

FIG. 2 is a plan view of the laboratory used in Examples 1-27; Figure 2 is a side view of the laboratory of Figure 1; 4 is a graph showing the results of evaluation experiments of Examples 1 to 6. FIG. 10 is a graph showing the results of evaluation experiments of Examples 7-12. 10 is a graph showing the results of evaluation experiments of Examples 13-22. 10 is a graph showing the results of evaluation experiments of Examples 23-25. 10 is a graph showing the results of Examples 26 and 27; FIG. 10 is a plan view of holes used in Examples 28-32; 9 is another plan view of the hole of FIG. 8; FIG. 10 is a graph showing the results of evaluation experiments of Examples 28-32. FIG. 11 is a plan view of a semi-private room used in Examples 33-34; Figure 12 is a front view of a wall of the semi-private room of Figure 11; Figure 12 is a front view of another wall of the semi-private room of Figure 11; Figure 12 is a front view of yet another wall of the semi-private room of Figure 11; 10 is a graph showing the results of evaluation experiments for Examples 33-37. FIG. 11 is a plan view of a semi-private room used in Examples 35-37; FIG. 17 is a plan view of the semi-private room shown in FIG. 16; Figure 17 is a front view of a wall of the semi-private room shown in Figure 16; Fig. 17 is a plan view of a store including the semi-private rooms shown in Figs. 11 and 16; It is Table 1 of Examples. It is Table 2 of an example. It is Table 3 of an example. It is Table 4 of Examples. It is Table 5 of an example. It is Table 6 of an example. FIG. 7 is Table 7 of Examples. It is Table 8 of an example. It is Table 9 of Examples. Table 10 of Examples. It is a block diagram of the evaluation device of this embodiment. 4 is a flowchart of an aerosol infection risk evaluation method performed using the evaluation device of the present embodiment. 10 is a flow chart of a method for evaluating the risk of HACCP-type aerosol infection, which is performed using the evaluation device of the modified example. 1 is a block diagram of an air cleaning system of this embodiment; FIG. 1 is a schematic diagram of an air cleaning device of the present embodiment; FIG. 4 is a flowchart of an aerosol infection risk evaluation method performed using the air cleaning system of the present embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention (hereinafter referred to as the present embodiment) will be described in the following order.
==================================
1. 2. Evaluation method of aerosol infection risk; 2. Method for reducing the risk of aerosol infection; Example 4. Summary and Supplement of 1 to 3 5. Aerosol infection risk assessment device and assessment program 6 . HACCP-type aerosol infection risk assessment device and assessment program7. air cleaning system 8 . Modification ==================================

Here, this specification has been prepared in two parts. Specifically, the above 1. ~3. is created in Phase 1, 4. ~8. was created in the second period after the first period. The contents of the description created in the second period are the addition of specific hardware after reviewing the contents created in the first period.

≪1. Evaluation method of aerosol infection risk≫
First, the method of evaluating the risk of aerosol infection according to this embodiment (hereinafter referred to as the evaluation method of this embodiment) will be described with reference to the drawings. The evaluation method of the present embodiment was created through diligent studies by the inventors of the present application in order to solve the above-described problems.

<Outline of the evaluation method of the present embodiment>
The evaluation method of this embodiment includes the following (1) to (3).
(1) Using a plurality of fine particles (2) Based on the recovery time t1 (an example of a specific elapsed time), which is the time required for the number of the plurality of fine particles to sufficiently decrease, the gathering space (defined (An example of a space having a large volume) to evaluate the particulate removal capacity (or referred to as "multiple particulate reduction capacity") (3) Compare the particulate removal capacity with the required ventilation capacity of the collective space thing

According to the evaluation method of the present embodiment, the behavior of droplet nuclei in aerosol can be simulated by the behavior of fine particles, and the substantial droplet nucleus removal ability of the customer space, which is difficult to evaluate only with the ventilation capacity of the facility, can be obtained. It can be easily evaluated. In addition, compared with the method using a tracer gas, fine particles simulating droplet nuclei can be visually observed, and the flow and diffusion of actual droplet nuclei can be easily grasped.

<Details of the evaluation method of the present embodiment>
Next, the evaluation method of this embodiment will be specifically described with reference to the drawings.

As an example, the evaluation method of this embodiment evaluates the infection risk of an infectious disease in a collective space in a facility.

[Definition, etc.]
An example of definitions of terms used in this specification will be described below.

"Infection risk" literally means the risk of contracting an infectious disease. In this embodiment, it means the risk of aerosol infection caused by pathogen-containing aerosols.

"Infectious disease" means a disease caused by invasion of a pathogen into the body, and "pathogen" means pathogenic (causing infectious disease) microorganisms. Examples of "pathogens" are viruses, bacteria, fungi, parasites, and the like.

“Aerosol” means a sol in which a plurality of fine particles are dispersed in air as a dispersion medium. In addition, “aerosol infection” means, for example, infection mediated by droplet nuclei (micro droplets) containing pathogens and having a particle diameter of 10 μm or less.

"Aerosol infection" is a different concept from "droplet infection". "Droplet infection" is an infection that occurs through droplets containing pathogens and water as a result of coughing or sneezing by an infected person or carrier, resulting in droplets being transmitted. Since the droplet particles have a relatively large particle diameter (particle diameter exceeding 10 μm) and are heavy, pathogens are said to scatter only within a range of approximately 1 m to 2 m.

On the other hand, "aerosol infection" is an infection that occurs mediated by droplet nuclei produced by evaporation of water from droplet particles. Droplet nuclei are relatively small and light particles, so they float in the air for a long time and spread over a wider area than droplets, which is said to be the cause of cluster formation. there is

In the evaluation method of this embodiment, the infection risk is the risk of aerosol infection caused by aerosols containing the new coronavirus, and as a method of evaluating the aerosol infection risk of the new coronavirus infection (COVID-19) in the gathering space. It is preferably used.

The evaluation method of the present embodiment includes, as an example, (1) a step of releasing a plurality of liquid particles into the collecting space, (2) a step of tracking the number of the plurality of liquid particles, and (3) the ability of the collecting space to remove particles. and (4) an evaluation step of the aerosol infection risk of the collective space. The steps (1) to (4) will be described below in the order described.

[(1) Step of releasing a plurality of liquid particles into a gathering space]
In this step, a plurality of liquid microparticles are emitted into the collection space using an emission source (not shown). For example, the average particle size of the plurality of liquid particles emitted from the emission source is preferably 10 μm or less. This is to understand the behavior of droplet nuclei by using droplet nuclei (micro-droplets) that mediate aerosol infection and that have an average particle size similar to that of droplet nuclei. In addition, the "average particle size" in the present specification is, for example, an average particle size measured by a laser light scattering method.

The component of each liquid microparticle that constitutes the plurality of liquid microparticles is not particularly limited. Components of each liquid microparticle may include, for example, ethylene glycol and water. For example, the drug solution that is the stock solution of each liquid particle includes the trade name "FLG5 Heavy Type" (manufactured by ANTARI).

The emission source of the plurality of liquid particles is also not particularly limited. The release source may have, for example, a mechanism for vaporizing the chemical solution by heating the chemical solution, which is the undiluted solution of the plurality of liquid particles, with a heater. An example of an emission source is a commercially available smoke machine (such as a stage smoke machine). The type of smoke machine is also not particularly limited. For example, there is a trade name "Z800II fog machine" (manufactured by ANTARI).

When the release source releases a plurality of liquid particles into the space to be evaluated, the release amount is preferably 50 mg/m ³ or more, for example. As a result, the influence of the number of other particles normally present in the space to be emitted (inside the collective space) is reduced, and the measurement of the plurality of liquid particles emitted from the emission source into the space ( It is possible to improve the S/N ratio at the time of measurement by a particle counter, which will be described later.

[(2) Step of Tracking Number of Plurality of Liquid Particles]
(1) After the step of discharging a plurality of liquid particles into the collecting space, in this step, the number of the plurality of liquid particles discharged into the collecting space is measured over time. Here, there is no particular limitation on means for measuring the quantity of the plurality of liquid particles in a timely manner. The measuring means is, for example, a densitometer that measures the particle concentration based on the weight method (filter weighing method), a particle counter that measures the number of multiple particles from the relative concentration calculated by the laser light scattering method, etc. is a measuring instrument.

Compared to the measurement method using a densitometer, the measurement method using a particle counter can measure the number of a plurality of liquid particles without being affected by the average particle size. Therefore, the measurement method using the particle measuring instrument is more accurate than the measurement method using the densitometer in time-keeping measurement of the number of a plurality of liquid particles that change in the air. Examples of particle counters include the trade name "DT-9880" (manufactured by CEM).

When measuring the number of a plurality of liquid particles in a time-keeping manner, as an example, it is preferable to measure the number of liquid particles having an average particle diameter of 0.3 μm or more and 10 μm or less. The reason for this is to track the behavior of droplet nuclei (micro droplets) that mediate aerosol infection and to understand the behavior of droplet nuclei by tracking the behavior of liquid particles that have an average particle size similar to that of droplet nuclei (micro droplets).

In addition, when measuring the number of multiple liquid particles in a chronological manner, in order to eliminate the influence of the number of other multiple particles that normally exist in the space to be measured (inside the collective space), the discharge process It is preferable to measure the number of the plurality of fine particles present in the aggregated space before and set the difference from the number as the number of the plurality of liquid fine particles.

[(3) Evaluation process of fine particle removal ability of collective space]
In this step, (2) during or after the step of tracking the number of the plurality of liquid particles, aggregation is performed based on the recovery time t1, which is the time required for the number of the plurality of liquid particles to sufficiently decrease. Evaluate the particulate removal capacity of the space.

"Particulate removal capability" means the ability to remove a plurality of liquid particulates from the air in the collective space being evaluated. "Particulate removal capacity" is a different concept from "ventilation capacity." "Ventilation capacity" means the ability to expel a plurality of liquid particles from inside the gathering space to the outside through a ventilation system such as a ventilation fan provided on the wall of the gathering space.

On the other hand, "fine particle removal ability" includes, for example, in addition to removal based on emissions by ventilation systems, removal based on emissions from openings provided in collective spaces such as windows, air purifiers, air conditioners, etc. It includes the ability to agitate air by means of liquids, decompose multiple liquid particles, and remove based on adsorption. In other words, in the present specification, the "particulate matter removing ability of a collective space, which is an example of an object to be evaluated," means the ability to remove a plurality of liquid particulates based on the configuration of the collective space. It should be noted that the term "fine particle removing ability" has the same meaning as the ability to reduce a plurality of liquid particulates, which will be described later. These abilities are evaluated more highly as the recovery time t1 is shorter.

"Sufficiently reduced" means that the number of multiple liquid particles emitted into the air in the collective space to be evaluated has decreased from the air, resulting in the number of multiple liquid particles in the air in the collective space to be evaluated. It means that the number of the microparticles present therein will be the same as the number of the microparticles before the release step.

"Time required for sufficient reduction" is, for example, the maximum number of multiple liquid particles present in the air in the collecting space after the discharge process, which is 1/100th of the number. corresponds to the elapsed time until it decreases to

Regarding reducing the amount to 1/100 when specifying the recovery time t1, it is assumed that if the amount of virus released into the air is diluted to 1/100 or less of the maximum value, the risk of infection disappears. There is an editorial (Proposed by Takayuki Miyazawa, Associate Professor, Department of Viral Coevolution, Institute for Frontier Medical Sciences, Kyoto University). Even if the virus exists, it is said that the person will not be infected unless a certain amount of the virus is taken into the body.

If the recovery time t1 is specified by one tenth, the recovery time t1 may vary depending on the average particle size of the plurality of liquid particles. For this reason, in order to accurately determine the particulate removal capability, the maximum number of liquid particulates present in the air in the collecting space after the discharge step should be reduced to 1/100th of that number. It is preferable to specify by the elapsed time until the time.

[(4) Evaluation process of aerosol infection risk in gathering space]
In this step, as an example, (3) is a step that is performed during or after the step of evaluating the particulate removal capacity of the gathering space, in which the particulate removal capability is compared with the required ventilation capacity of the gathering space, and the particulate removal capability Evaluate the collective space as having a low aerosol infection risk (or no aerosol infection risk) if is equal to or greater than the required ventilation capacity.
Here, as a specific method of evaluation in this step, as an example, it is as follows.

<(4A) First infection risk evaluation method>
The first infection risk evaluation method compares the amount of removed fine particles Q1 and the required ventilation amount Q2, and when the amount of removed particles Q1 is equal to or greater than the required ventilation amount Q2, the risk of aerosol infection in the gathering space is low. (or there is no risk of aerosol infection), and when the amount of removed fine particles Q1 is less than the ventilation requirement Q2, the risk of aerosol infection in the collective space is evaluated as high (or there is a risk of aerosol infection).

In the first infection risk evaluation method, the ability to remove fine particles is calculated from the following formula (1). The particle removal amount Q1 is the number of a plurality of liquid particles per 1 [m ³ ] removed in 60 [minutes] in the gathering space to be evaluated. Since the recovery time t1 can be regarded as the time required to remove all liquid particles that have been discharged into the collective space and filled the collective space, the amount of removed fine particles Q1 is determined by the volume V of the collective space and the recovery time. It can be calculated from t1.

Formula (1): Particle removal amount Q1 [m ³ /hour]=Volume of collective space V [m ³ ]×60 [minute]/Recovery time t1 [minute]

In addition, in the first infection risk evaluation method, the required ventilation volume is defined by the required ventilation volume Q2 calculated by the following equation (2). The required ventilation volume Q2 is the ventilation volume required for the gathering space to be measured according to the number of people accommodated, and is calculated from the required ventilation volume per customer and the accommodation capacity n of the gathering space. be able to.

Formula (2): Person required ventilation Q2 [m ³ /hour] = Required ventilation per customer [m ³ /hour/person] × Capacity of meeting space n [person]

According to the first infection risk evaluation method, as an example, the infection risk can be evaluated more accurately by taking into account the volume of the gathering space, its accommodation capacity, and the like. Depending on ventilation, etc., it may not be possible to secure a sufficient amount of fine particle removal, and measures may be taken to reduce the accommodation capacity n, but according to the first infection risk assessment method, the impact of accommodation capacity n Considered evaluation is done.

As the required ventilation volume per customer, in Japan, it is possible to appropriately adopt from among the required ventilation volume values stipulated by the relevant laws and regulations. For example, 20 [m ³ /h] (value based on Article 20-2 of the Enforcement Order of the Building Standards Act), 30 [m ³ /h] (based on the environmental hygiene standards of the Act on Ensuring Sanitary Environments in Buildings and the value indicated by the Ministry of Health, Labor and Welfare as necessary from the perspective of corona countermeasures). The standards based on these laws and regulations are the values determined by environmental sanitation experts from the viewpoint of preventing infectious diseases, and are reliable values.

For reference, an example of the calculation method based on the law (Article 20-2 of the Enforcement Order of the Building Standards Law) is shown below.

The effective ventilation volume (equivalent to the “required ventilation volume” in this specification) should be equal to or greater than the value calculated by the following formula.
(Formula): V = 20Af/N
In this formula, V, Af and N shall represent the following numerical values, respectively.
V: Effective ventilation volume [pieces/hour/m ³ ]
Af: Floor area of a living room [m ² ] (If a living room other than a living room in a special building has windows or other openings that are effective for ventilation, obtain by multiplying the effective area for ventilation of the opening by 20. area obtained by subtracting the floor area of the room)
N: Occupied area per person according to actual conditions [m ² ] (3 if more than 3 in a room in a special building, and 10 if more than 10 in other rooms)

<(4B) Second infection risk evaluation method>
The second infection risk evaluation method compares the number of times N1 for removing fine particles and the required number of ventilations N2, and if the number of times N1 for removing fine particles is equal to or greater than the required number of ventilations N2, the risk of aerosol infection in the collective space is low (or If the fine particle removal frequency N1 is less than the required ventilation frequency N2, the collective space is evaluated as having a high aerosol infection risk (or there is an aerosol infection risk).

In the second infection risk evaluation method, the ability to remove fine particles is evaluated by the number of times N1 of removing fine particles calculated by the following equation (3). The particulate removal frequency N1 indicates how many times per hour all the liquid particulates discharged and filled in the collective space to be evaluated can be removed. Since the recovery time t1 can be regarded as the time required to remove all liquid particles that have been released into the collecting space and filled the collecting space, the number of times N1 of removing fine particles can be calculated from the recovery time t1. can.

Formula (3): Number of particle removal times N1 [times/hour]=60 [minutes]/recovery time t1 [minutes]

Also, in the second infection risk evaluation method, the required ventilation volume is defined by the required ventilation frequency N2 of the collective space determined in accordance with the guidelines of the hygiene laboratory. The required ventilation frequency N2 is the ventilation frequency determined according to the business type and purpose of use of the collective space to be evaluated, and specifies how many times per hour the air that fills the collective space should be ventilated (replaced). is. For example, in the case of cafeterias and restaurants, the required ventilation frequency is stipulated as 6 [times/hour].

The second infection risk assessment method is effective in that even if the volume of the gathering space and the number of people that can be accommodated are unclear, the infection risk can be easily assessed as long as the business type and purpose of use are known. . However, since the hygiene laboratory guidelines are based on the average occupancy density based on the type of industry and purpose of use, it is preferable to use the first infection risk assessment method if a more accurate assessment is desired. .

<(4C) Third infection risk evaluation method>
The third infection risk evaluation method compares the recovery time t1 and the required ventilation time t2, and if the recovery time t1 is equal to or greater than the required ventilation time t2, the risk of aerosol infection in the collective space is low (or the risk of aerosol infection ), and when the recovery time t1 is less than the required ventilation time t2, the risk of aerosol infection in the collective space is evaluated as high (or there is a risk of aerosol infection).

In the third infection risk evaluation method, the ability to remove fine particles is determined from the recovery time t1. Further, in the third infection risk evaluation method, the required ventilation volume is specified by the required ventilation time t2 calculated by the following formula (4). The required ventilation time t2 defines the maximum time required to remove the air that fills the collective space under evaluation. The required ventilation time t2 can be converted from the required ventilation frequency N2.

Formula (4): Required ventilation time t2 [minutes] = 60 [minutes] / Required ventilation frequency N2 [times/hour]

The third infection risk assessment method is similar to the second infection risk assessment method, even if the volume of the gathering space and the number of people that can be accommodated are unclear, the infection risk can be easily determined if the business type and purpose of use are known. It is effective in that it can evaluate However, since the hygiene laboratory guidelines are based on the average occupancy density based on the type of industry and purpose of use, it is preferable to use the first infection risk assessment method if a more accurate assessment is desired. .

<(4D) Fourth infection risk evaluation method>
The fourth infection risk evaluation method compares the amount of removed fine particles Q1 and the required area ventilation amount Q3, and when the amount of removed particles Q1 is equal to or greater than the required area ventilation amount Q3, the risk of aerosol infection in the gathering space is low. (or there is no risk of aerosol infection), and when the amount of removed fine particles Q1 is less than the required area ventilation Q3, the risk of aerosol infection in the collective space is evaluated as high (or there is a risk of aerosol infection).

In the fourth infection risk evaluation method, the ability to remove fine particles is calculated from equation (1) of the first infection risk evaluation method. Further, in the fourth infection risk evaluation method, the required ventilation volume is defined by the area required ventilation volume Q3 calculated from the following equation (5). Whereas the required human ventilation Q2 used in the first infection risk assessment method was the ventilation determined based on the volume V of the collective space, the required area ventilation Q3 was determined based on the floor area of the collective space. is the amount of ventilation that is

Formula (5): Area required ventilation Q3 [m ³ /h] = required ventilation per floor area [m ^{3 /} m ² /h] x floor area of collective space [m ² ]

The area required ventilation Q3 can be calculated from the required ventilation per floor area and the floor area of the collective space. Here, the required floor space ventilation volume is a value defined in the Air Conditioning and Sanitary Engineers Society Standard (HASS 102 1972). The floor area required ventilation volume is determined according to the type of industry and purpose of use of the collective space to be evaluated. For example, in the case of cafeterias and restaurants, the required floor area ventilation volume is 30 [m ³ /m ² /hour] for “restaurants and cafes (normal)” and 17.7 [m ³ /hours] for “restaurants and cafes (luxury)”. m ² /h].

In the fourth infection risk assessment method, even if the volume and capacity of the gathering space are unclear, the infection risk can be easily assessed if the business type, purpose of use, and floor area of the space are known. is valid at the point. For example, the floor area is described in the restaurant business license, etc., and there is a high possibility that the business owner is aware of it. However, since the hygiene laboratory guidelines are based on the average occupancy density based on the type of industry and purpose of use, it is preferable to use the first infection risk assessment method if a more accurate assessment is desired. .

≪2. How to reduce the risk of aerosol infection≫
The infection risk reduction method of this embodiment reduces the infection risk of an infectious disease in a gathering space. Specifically, as a result of performing the infection risk evaluation method of this embodiment, when the evaluation target gathering space is evaluated to have a high aerosol infection risk, the level at which the aerosol infection risk in the gathering space is low (for example , until the fine particle removal capacity becomes equal to or greater than the required ventilation capacity), the following improvement measures will be taken.

Specific examples of improvement measures include, in addition to improving the capacity of ventilation systems such as ventilation fans, ventilation by opening windows, doors, or vents, operation of air conditioners, circulators, or air purifiers, installation of shielding plates or partitions, and housing. Examples include taking at least one measure selected from the group consisting of reduction in capacity. These remedial measures can be suitably used to reduce the risk of infection in facilities where the ventilation system cannot be enhanced for some reason.

By the way, in the measures to prevent infection with the new coronavirus infectious disease that have been implemented in Japan so far, infected people with new coronavirus infectious diseases are discovered by PCR tests or antigen tests, and facilities are identified from the behavioral history of infected people ( active epidemiological survey), and by restricting the use of facilities similar in size, structure, etc. to facilities where clusters occurred. However, there is little scientific basis for regulating the use of similar facilities, and it is unclear whether or not they are effective. The infection prevention measures mentioned above are causing confusion in Japanese society and causing excessive contraction of economic activity in Japan.

On the other hand, the infection risk evaluation method of this embodiment evaluates the environment of a specific space regardless of whether or not it is actually infected, and objectively determines whether the space is taking measures to prevent infection. It is effective in that it can be evaluated and can give facility users a sense of security. In addition, since the infection risk reduction method of the present embodiment is performed based on the results of the infection risk evaluation method of the present embodiment, it is effective in that the infection risk can be appropriately reduced.

≪3. Example>>
Examples of the infection risk evaluation method and the infection risk reduction method of the present embodiment will be described below.

The evaluation of Examples 1-27 was conducted in Laboratory 1 shown in FIGS. Laboratory 1 was assumed to be a restaurant. The laboratory 1 is 2.6 m long (vertical direction in FIG. 1), 3.0 m wide (horizontal direction in FIG. 1), and 2.4 m high, with a floor area of 7.8 m ² and a volume V of 18.5 m ³ . is the room.

The capacity n of the laboratory 1 was 6, and the required ventilation per customer was 30 [m ³ /hour]. From these values and equation (2), the required human ventilation Q2 [m ³ /hour] is calculated to be 180 [m ³ /hour]. Also, the laboratory 1 corresponds to "dining room, restaurant, sushi bar" in the guideline of the hypothetical sanitation laboratory, and the required ventilation frequency N2 is 6 times. From this value and equation (4), the required ventilation time t2 [minutes] is calculated as 10 [minutes].

Furthermore, the laboratory 1 corresponds to "restaurant / coffee shop (luxury)" in the air conditioning and sanitary engineering society standard (HASS 102 1972), and the required ventilation amount per floor area is 17.7 [m ³ /m ² / hour], The floor area is ^7.8m2 . From these values and Equation (5), the area required ventilation Q3 [m ³ /hour] is calculated to be 138 [m ³ /hour].

Table 1 in FIG. 20 shows the required human ventilation Q2, the required number of ventilations N2, the required ventilation time t2, and the required area ventilation Q3 in Laboratory 1 under the above conditions. By comparing these values with the measured values, the relationship between the particle removal amount Q1 ≥ the required ventilation volume Q2 (or the required area ventilation volume Q3), the number of particle removal times N1 ≥ the required ventilation rate N2, and the recovery time t1 ≥ the required ventilation time t2. If the conditions are satisfied, the risk of infection is evaluated as low, and if the conditions are not satisfied, the risk of infection is evaluated as high.

Infection risk evaluation is carried out by emitting liquid particles 4 from a smoke machine 2 in a laboratory 1 shown in FIGS. It was carried out by evaluating the ability to remove fine particles based on the time (recovery time) required for the .

1 and 2, reference numeral 8 denotes a ventilation fan, reference numeral 10 denotes an air conditioner, reference numerals 12 and 14 denote windows, reference numeral 16 denotes a door, and reference numeral 18 denotes an installation table.

In the examples, as the smoke machine, trade name "Z800II Fog Machine" (manufactured by ANTARI Co., Ltd.), as the chemical solution to be the stock solution of liquid fine particles, trade name "FLG5 Heavy Type" (manufactured by ANTARI Co., Ltd.), and the particle counter. As such, the product name "DT-9880" (manufactured by CEM) was used.

[Influence of particle size of liquid fine particles]
(Example 1)
In the laboratory 1 shown in FIGS. 1 and 2, 300 mg/m ³ of liquid particles 4 were emitted from the smoke machine 2 and the decrease in the number of the liquid particles 4 having a particle diameter of 0.3 μm was tracked by the particle counter 6 . In order to simulate a collective space in which a sufficient amount of ventilation is ensured, the amount of ventilation of the ventilation fan 8 was set to 1000 m ³ /hour. The evaluation results are shown in Table 2 of FIG. 21 and FIG. Note that the graph shown in FIG. 3 is a graph that traces the decrease in the number of liquid particles. In this graph, the number of liquid microparticles at the time of measurement is plotted as a percentage of the maximum number of liquid microparticles after ejection of the liquid microparticles (the same applies to graphs shown in subsequent drawings).

(Example 2-6)
A decrease in the number of liquid particles was tracked in the same manner as in Example 1, except that the particle size of the liquid particles to be detected was changed to the value shown in Table 2. The results are shown in Table 2 of FIG. 21 and FIG.

(Example 7-12)
In order to simulate a collective space with insufficient ventilation, except that the ventilation rate of the ventilation fan 8 shown in FIGS. tracked the decline. The results are shown in Table 3 of FIG. 22 and FIG.

Under the conditions of Examples 1-6 with sufficient ventilation, the risk of infection was evaluated to be low when liquid particulates of any particle size were tracked. In addition, even under the conditions of Examples 7 to 12 where the ventilation volume was insufficient, the risk of infection was evaluated to be high when liquid particulates of any particle size were tracked. In other words, the same evaluation results could be obtained regardless of the particle size of the liquid particles.

However, as far as the data of Examples 1-12 are concerned, the recovery time t1 tends to become shorter as the particle size increases. The reason for this is thought to be that when the particle diameter of the liquid particles increases, the liquid particles settle and are removed from the space. Therefore, it can be said that the smaller the particle size, the more accurate the evaluation. In that respect, it can be said that it is preferable to trace liquid particles with a particle size of 0.3 μm or more and 2.5 μm or less, and it can be said that it is more preferable to trace liquid particles with a particle size of 0.3 μm or more and 0.5 μm or less.

[Influence of emission amount of liquid fine particles]
(Example 13)
In the laboratory 1 shown in FIGS. 1 and 2, 517 g/m ³ of liquid fine particles 4 were discharged from the smoke machine 2 and the decrease in the number of the liquid fine particles 4 having a particle diameter of 0.3 μm was tracked by the fine particle counter 6 . The ventilation amount of the ventilation fan 8 was set to 600 m ³ /hour. The evaluation results are shown in Table 4 of FIG. 23 and FIG.

(Examples 14-22)
The decrease in the number of liquid microparticles was tracked in the same manner as in Example 13, except that the amount of liquid microparticles emitted was changed to the value shown in Table 4. The results are shown in Table 4 of FIG. 23 and FIG.

In Examples 13 to 19, the risk of infection was evaluated to be high regardless of the amount of liquid microparticles released. In other words, similar evaluation results could be obtained in the range of the discharged amount of liquid fine particles from 50 to 517 mg/m ³ .

However, in Examples 20-22, the risk of infection was evaluated as low, showing a different tendency from Examples 13-19. It can be said that this indicates the possibility that when the amount of emitted liquid particles decreases, the number of particles existing in the natural environment becomes more susceptible, and accurate evaluation may not be possible depending on the measurement conditions. That is, it can be said that it is preferable to release a sufficient amount of liquid particles, specifically 50 mg/m ³ or more, so that the influence of the number of particles present in the natural environment can be ignored.

[Improvement effect of infection risk by air purifier and electric fan]
(Example 23)
In the laboratory 1 shown in FIGS. 1 and 2, 300 g/m ³ of liquid fine particles 4 were emitted from the smoke machine 2, and the particle diameter of 0.3 μm was measured by the fine particle measuring device 6 while the air cleaner and the electric fan were being operated. A decrease in the number of liquid particulates 4 was tracked.

The ventilation amount of the ventilation fan 8 was set to 400 m ³ /hour. As the air cleaner, a humidified air cleaner (trade name: KC-G40-W, manufactured by Sharp) was used and operated under the condition of cleaning 240 m ³ of air per hour. As the fan, a living room fan (trade name: AMT-KC30, manufactured by Yamazen) was used and operated at the maximum air volume. Evaluation results are shown in Table 5 and FIG.

(Examples 24 and 25)
The decrease in the number of liquid particulates was tracked in the same manner as in Example 23, except that the operating conditions of the air purifier and fan were changed as shown in Table 5 of FIG. The results are shown in Table 5 of FIG. 24 and FIG.

The recovery time t1 is shorter in the order of Example 25 in which both the air cleaner and the fan are stopped, Example 24 in which only the air cleaner is operated, and Example 23 in which both the air cleaner and the fan are operated. In other words, the effect of reducing the risk of infection was recognized by operating air purifiers and electric fans. However, Examples 24 and 23 were also not evaluated as having a "low risk of infection", and it was recognized that additional improvement measures were necessary.

[Improving effect of air conditioner on infection risk]
(Example 26)
In the laboratory 1 shown in FIGS. 1 and 2, 300 g/m ³ of liquid particles 4 were emitted from the smoke machine 2 and the air conditioner was operated. We tracked the decline in quantity.

The ventilation amount of the ventilation fan 8 was set to 400 m ³ /hour. As the air conditioner, a product name: CSH-B2220R manufactured by Corona was used and operated at the maximum cooling/air volume. The evaluation results are shown in Table 6 of FIG. 25 and FIG.

(Example 27)
The decrease in the number of liquid particulates was followed in the same manner as in Example 26, except that the air conditioner was turned off. The results are shown in Table 6 of FIG. 25 and FIG.

Compared with Example 27 in which the air conditioner was stopped, Example 26 in which the air conditioner was operated had a shorter recovery time t1. In other words, the effect of reducing the risk of infection was recognized by operating the air conditioner. However, even Example 26 was not evaluated as having a "low risk of infection", and it was recognized that additional improvement measures were necessary.

[Example 1 of improving the risk of infection at a physical store]
The evaluation of Examples 28-32 was conducted in Izakaya Hall 101 shown in FIGS. The hall 101 is 4.9 m long (vertical direction in FIG. 8), 4.85 m wide (horizontal direction in FIG. 8), and 2.69 m high, with a floor area of 23.8 m ² and a volume V of 63.9 m ³ . is.

The capacity n of the hall 101 is 14, and the ventilation required per customer is 30 [m ³ /hour]. From these values and equation (2), the required human ventilation Q2 [m ³ /hour] is calculated to be 420 [m ³ /hour]. Hall 101 corresponds to "cafeteria, restaurant, sushi bar" in the guideline of the hypothetical sanitation laboratory, and the required ventilation frequency N2 is 6 times. From this value and equation (4), the required ventilation time t2 [minutes] is calculated as 10 [minutes].

Furthermore, hall 101 corresponds to "restaurants and cafes (luxury)" according to the Air Conditioning and Sanitary Engineering Society standards (HASS 102 1972), and the required ventilation volume per floor area is 17.7 [m ³ /m ² /hour]. The area is 23.8 ^m2 . From these values and equation (5), the area required ventilation Q3 [m ³ /hour] is calculated as 420 [m ³ /hour].

Table 7 in FIG. 26 shows the required human ventilation Q2, the required number of ventilations N2, the required ventilation time t2, and the required area ventilation Q3 of Laboratory 1 under the above conditions. By comparing these values with the measured values, the relationships between the particle removal amount Q1 ≥ the required ventilation volume Q2 (or the required area ventilation volume Q3), the particle removal frequency N1 ≥ the required ventilation frequency N2, and the recovery time t1 ≤ required ventilation time t2. If the conditions are satisfied, the risk of infection is evaluated as low, and if the conditions are not satisfied, the risk of infection is evaluated as high.

(Example 28)
In the hall 101 shown in FIGS. 8 and 9, 300 g/m3 of liquid particles are discharged from the smoke machine, and the air purifiers 110 (two units), the air conditioners 114 (two units), and the total heat exchanger 112 are operated. , the decrease in the number of liquid particles with a particle diameter of 0.3 μm was tracked by the particle counter 106 .

The ventilation volume of the ventilation fan 108 (two units) was set to 170 m ³ /hour, and the ventilation volume of the ventilation fan 109 was set to 78 m ³ /hour. As the air purifier 110, a humidified streamer air purifier (trade name: ACK55X, manufactured by Daikin Industries, Ltd.) was used and operated under the condition of purifying 330 m ³ of air per hour. As the air conditioner 114, an installed commercial air conditioner (model unknown) was used, and was operated at the maximum cooling/air volume. A total heat exchanger unit (trade name: VAH500GB, manufactured by Daikin Industries) was used as the total heat exchanger 112, and the ventilation rate was set to 500 m3/hour. The evaluation results are shown in Table 8 of FIG. 27 and FIG.

(Examples 29-32)
The decrease in the number of liquid particulates was tracked in the same manner as in Example 28, except that the operating conditions of the air purifier, air conditioner, and total heat exchanger were changed as shown in Table 8 of FIG. The results are shown in Table 8 of FIG. 27 and FIG.

Example 32 in which the air cleaner, air conditioner and total heat exchanger were all stopped, Example 31 in which only the air conditioner was operated, Example 30 in which the air conditioner and total heat exchanger were operated, one air cleaner, and an air conditioner The recovery time t1 is shorter in the order of Example 29 in which the total heat exchanger is operated, and Example 28 in which two air cleaners, the air conditioner and the total heat exchanger are operated. In other words, it was confirmed that operating an air purifier, air conditioner, or total heat exchanger was effective in reducing the risk of infection. In addition, for Example 28, these improvement measures could improve the hole 101 shown in FIGS. 8 and 9 of FIG. rice field.

[Example 2 of improving the risk of infection at a physical store]
The evaluation of Examples 33-34 was conducted in a semi-private room 201 of a pub shown in FIG. The semi-private room 201 is ^2.3 m long (vertical direction in FIG. 11), 3 m wide (horizontal direction in FIG. 11), and 2.7 m high, with a floor area of 6.9 m2 and a volume V of 18.6 m3. . The semi-private room 201 is not equipped with an air conditioner or a ventilation fan. Further, as shown in FIG. 13, one wall 222 of the four walls partitioning the semi-private room 201 has two windows 224 communicating with the outside. Transoms 220A, 226A, and 228A are formed in the upper portions of three walls 220, 226, and 228, respectively. Furthermore, as shown in FIG. 12, crosspieces 216A are incorporated in the upper and lower portions of the sliding door 216 to form a plurality of gaps. The transom part of the wall and the crosspiece part of the door communicate with the outside of the semi-private room, and have a structure that allows ventilation (ventilation).

FIG. 19 shows the air-conditioning equipment of a store including a semi-private room 201 of a pub shown in FIG. 11 and a semi-private room 301 shown in FIG. 16 which will be described later. A ventilation fan 408 , an air cleaner 410 , a total heat exchanger 412 , an air conditioner 414 , a sliding door 416 and a window 424 are installed outside the semi-private rooms 201 and 301 . In Tables 8 and 10, "open" of the window means that not only the window 224 but also the window 424 are open, and "closed" of the window means that the windows 224 and 424 are closed. Further, "running" of the air conditioner means that not only the air conditioner 314 but also the air conditioner 414 is running, and "stop" of the air conditioner means that the air conditioners 314 and 414 are stopped. Furthermore, “run” and “stop” of the air purifier indicate the operation/stop of the air cleaner 410 , and “operate” and “stop” of the total heat exchanger indicate the operation/stop of the total heat exchanger 412 .

The accommodation capacity n of the semi-private room 201 is 8, and the ventilation required per customer is 30 [m ³ /hour]. From these values and equation (2), the required human ventilation Q2 [m ³ /hour] is calculated as 240 [m ³ /hour]. In addition, the semi-private room 201 corresponds to "dining room, restaurant, sushi restaurant" in the guideline of the assumed sanitation laboratory, and the required ventilation frequency N2 is 6 times. From this value and equation (4), the required ventilation time t2 [minutes] is calculated as 10 [minutes].

Furthermore, the semi-private room 201 corresponds to "restaurant/cafe (normal)" in the Air Conditioning and Sanitary Engineering Society Standard (HASS 102 1972), the required ventilation amount per floor area is 30 [m ³ /m ² / hour], and the floor area is 6.9 ^m2 . From these values and equation (5), the area required ventilation Q3 [m ³ /hour] is calculated as 207 [m ³ /hour].

Table 9 in FIG. 28 shows the required person ventilation Q2, the required ventilation frequency N2, the required ventilation time t2, and the area required ventilation Q3 of the semi-private room 201 under the above conditions. By comparing these values with the measured values, the relationship between the particle removal amount Q1 ≥ the required ventilation volume Q2 (or the required area ventilation volume Q3), the particle removal frequency N1 ≥ the required ventilation frequency N2, and the recovery time t1 ≤ the required ventilation time t2. If the conditions are satisfied, the risk of infection is evaluated as low, and if the conditions are not satisfied, the risk of infection is evaluated as high.

(Example 33)
In the semi-private room 201 shown in FIGS. 11 and 19, 300 g/m ³ of liquid particles are emitted from the smoke machine, the windows 224 and 424 are closed, and the ventilation fan 408, air cleaner 410 and total heat exchanger 412 are operated. , the decrease in the number of liquid particles with a particle diameter of 0.3 μm was tracked by the particle counter 206 .

The air purifier 410 and total heat exchanger 412 were of the same model as those used in Example 28, and were operated under the same operating conditions as in Example 28. Evaluation results are shown in Table 10 and FIG.

(Example 34)
The number of liquid particulates was determined in the same manner as in Example 33, except that the opening and closing conditions of the windows 224 and 424 and the operating conditions of the air purifier 410 and the total heat exchanger 412 were changed as shown in Table 10 of FIG. tracked a decline in The results are shown in Table 10 of FIG. 29 and FIG.

From Example 33 in which the windows 224 and 424 were closed and the air cleaner 410 and the total heat exchanger 412 were operated, the windows 224 and 424 were opened and the air cleaner 410 and the total heat exchanger 412 were operated. The recovery time t1 of Example 34 is much shorter. In other words, it was confirmed that opening the windows 224 and 424 had the effect of reducing the risk of infection. In addition, with regard to Example 34, the semi-private room 201 shown in FIGS. 5 and 6 could be improved to an evaluation of "low risk of infection" by these improvement measures, and a particularly good improvement effect was obtained.

[Example 3 of improving the risk of infection at a physical store]
The evaluation of Examples 35-37 was conducted in a semi-private room 301 of a pub shown in FIGS. The semi-private room 301 is 1.8 m long (vertical direction in FIG. 16), 3.3 m wide (horizontal direction in FIG. 16), and 2.7 m high, with a floor area of 5.9 m ² and a volume V of 16 m ³ . be. Semi-private room 301 has the same structure as semi-private room 201 shown in FIG. 11 except that it does not have a window. Specifically, the wall containing the sliding door 316 is constructed similarly to the wall 220 shown in FIG. 12, and the two walls adjacent to the wall containing the sliding door 316 are constructed similarly to the walls 226, 228 shown in FIG. A wall 322 facing the wall having the sliding door 316 has a transom 322A formed in the upper part of the wall 322, as shown in FIG. That is, transoms are formed in the upper portions of the four walls that partition the semi-private room 301, and rails are incorporated above and below the sliding door 316 to form a plurality of gaps. The transom part of the wall and the crosspiece part of the door communicate with the outside of the semi-private room, and have a structure that allows ventilation (ventilation).

The accommodation capacity n of the semi-private room 301 was set to 8, and the required ventilation volume per customer was set to 30 [m ³ /hour]. From these values and equation (2), the required human ventilation Q2 [m ³ /hour] is calculated as 240 [m ³ /hour]. Further, the semi-private room 301 corresponds to "dining room, restaurant, sushi restaurant" in the guideline of the hypothetical sanitation laboratory, and the required ventilation frequency N2 is 6 times. From this value and equation (4), the required ventilation time t2 [minutes] is calculated as 10 [minutes].

Furthermore, the semi-private room 301 corresponds to "restaurant/cafe (normal)" in the Air Conditioning and Sanitary Engineering Society Standard (HASS 102 1972), the required ventilation amount per floor area is 30 [m ³ /m ² / hour], and the floor area is 5.9 ^m2 . From these values and equation (5), the area required ventilation Q3 [m ³ /hour] is calculated to be 177 [m ³ /hour].

Table 11 in FIG. 30 shows the required person ventilation Q2, the required ventilation frequency N2, the required ventilation time t2, and the area required ventilation Q3 of the semi-private room 301 under the above conditions. By comparing these values with the measured values, the relationship between the particle removal amount Q1 ≥ the required ventilation volume Q2 (or the required area ventilation volume Q3), the particle removal frequency N1 ≥ the required ventilation frequency N2, and the recovery time t1 ≤ the required ventilation time t2. If the conditions are satisfied, the risk of infection is evaluated as low, and if the conditions are not satisfied, the risk of infection is evaluated as high.

(Example 35)
In the semi-private room 301 shown in FIGS. 16 and 19, 300 g/m ³ of liquid particles are emitted from the smoke machine, the windows 224 and 424 are closed, the ventilation fan 408, the air cleaner 410 and the total heat exchanger 412 are operated, and the air conditioner is operated. With the devices 314 and 414 stopped, the particle counter 306 tracked the decrease in the number of liquid particles with a particle diameter of 0.3 μm.

17 and 19 show the arrangement of the air conditioner 314 and the total heat exchanger 412. FIG. The air purifier 410 and total heat exchanger 412 were of the same model as those used in Example 28, and were operated under the same operating conditions as in Example 28. Ceiling-embedded air conditioners (trade name: FHCP160EC, manufactured by Daikin Industries) were used as the air conditioners 314 and 414, and were operated at the maximum cooling/air volume. The evaluation results are shown in Table 10 of FIG. 29 and FIG.

(Examples 36 and 37)
The decrease in the number of liquid particulates was tracked in the same manner as in Example 35, except that the operating conditions of the air purifier 410, air conditioners 314, 414, and total heat exchanger 412 were changed as shown in Table 10. . The results are shown in Table 10 of FIG. 29 and FIG.

Example 35 in which the windows 224, 424 were closed, the air conditioners 314, 414 were stopped, and the air cleaner 410 and the total heat exchanger 412 were operated; Example 36 in which 414 and total heat exchanger 412 were operated, and Example 37 in which windows 224 and 424 were opened and all of air cleaner 410, air conditioners 314 and 414 and total heat exchanger 412 were operated. The recovery time t1 is shortened. In other words, opening the windows and operating air purifiers, air conditioners, and total heat exchangers was effective in reducing the risk of infection. However, none of Examples 35-37 was evaluated as having a "low risk of infection", and it was recognized that additional improvement measures were necessary.

Even under the same conditions as in Example 37, by additionally installing an air purifier or a total heat exchanger, or by reducing the capacity of the semi-private room 301, the semi-private room 301 can be treated as an infection risk. It is possible to improve the evaluation to "low".

For example, in Example 37, the particle removal amount Q1 is 139 [m ³ /hour], which is lower than the ventilation requirement Q2 of 240 [m ³ /hour], so the risk of infection is evaluated to be high. However, if the accommodation capacity n of the semi-private room 301 is reduced from 8 to 4, the required ventilation Q2 per person decreases to 120 [m ³ /hour]. That is, if the accommodation capacity n of the semi-private room 301 is 4 people, the fine particle removal amount Q1 (139 [m ³ /hour]) exceeds the required ventilation amount Q2 of 120 [m ³ /hour], and the risk of infection is low. can be evaluated as

≪Summary and Supplement of 4.1 to 3≫
The following is a summary and supplementary explanation of 1 to 3 created in the first term.

<Summary>
The descriptions of 1 to 3 and the referenced drawings include the following inventions. Here, a plurality of inventions are described as Appendices 1 to 13, respectively.

[Appendix 1]
An infection risk assessment method for assessing the infection risk of an infectious disease in a gathering space inside a facility,
The infection risk is the risk of aerosol infection caused by a pathogen-containing aerosol,
ejecting liquid particulates into said gathering space;
After releasing the liquid particulates, tracking the decrease in the amount of the liquid particulates over time;
Based on the recovery time t1, which is the time required for the amount of liquid particles to sufficiently decrease,
Evaluating the particulate removal ability of the gathering space,
Comparing the particulate removal capacity with the required ventilation capacity of the gathering space, and evaluating that the gathering space has a low aerosol infection risk when the particulate removal capability is equal to or greater than the required ventilation capacity. .
[Appendix 2]
The infection risk assessment method according to Supplementary Note 1,
Among the liquid microparticles, the amount of liquid microparticles having a particle diameter of 0.3 μm or more and 10 μm or less is tracked over time.
[Appendix 3]
The infection risk assessment method according to Supplementary Note 1,
The decrease in the amount of liquid particulates is tracked by a particulate counter.
[Appendix 4]
The infection risk assessment method according to Supplementary Note 1,
The ability to remove fine particles is evaluated by the amount Q1 of fine particles removed calculated by the following formula (1),
The required ventilation volume is defined by the required ventilation volume Q2 calculated by the following formula (2),
The amount of removed fine particles Q1 and the required ventilation amount Q2 are compared, and if the amount of removed particles Q1 is equal to or greater than the required ventilation amount Q2, it is determined that the risk of aerosol infection in the gathering space is low. what to evaluate.
Formula (1): Particle removal amount Q1 [m ³ /hour]=Volume of collective space V [m ³ ]×60 [minutes]/Recovery time t1 [minutes]
Formula (2): Necessary ventilation volume Q2 [m ³ /hour] = Necessary ventilation volume per customer [m ³ /hour/person] × Accommodating capacity of the gathering space n [person]
[Appendix 5]
The infection risk assessment method according to Supplementary Note 1,
The ability to remove fine particles is evaluated by the number of times N1 of removing fine particles or the recovery time t1 calculated by the following formula (3),
The required ventilation volume is defined by the required ventilation frequency N2 of the collective space determined in accordance with the guidelines of the hygiene laboratory or the required ventilation time t2 calculated by the following formula (4),
When the particle removal frequency N1 and the required ventilation frequency N2 are compared, or the recovery time t1 and the required ventilation time t2 are compared, and the particle removal frequency N1 is equal to or greater than the required ventilation frequency N2, or When the recovery time t1 is equal to or greater than the required ventilation time t2, the risk of aerosol infection in the collective space is evaluated as low.
Formula (3): Number of particle removal times N1 [times/hour]=60 [minutes]/recovery time t1 [minutes]
Formula (4): Required ventilation time t2 [minutes] = 60 [minutes] / Required ventilation frequency N2 [times/hour]
[Appendix 6]
The infection risk assessment method according to Supplementary Note 1,
The ability to remove fine particles is evaluated by the amount Q1 of fine particles removed calculated by the following formula (1),
The required ventilation volume is defined by the area required ventilation volume Q3 calculated by the following formula (5),
The particulate removal amount Q1 is compared with the required area ventilation amount Q3, and if the particulate removal amount Q1 is equal to or greater than the required area ventilation amount Q3, the risk of aerosol infection in the gathering space is low. what to evaluate.
Formula (1): Particle removal amount Q1 [m ³ /hour]=Volume of collective space V [m ³ ]×60 [minutes]/Recovery time t1 [minutes]
Formula (5): Area required ventilation Q3 [m ³ /h] = required ventilation per floor area [m ³ /m ² /h] x floor area of collective space [m ² ]
(However, the required ventilation volume per floor area shall be the value specified in the Air Conditioning and Sanitary Engineering Society Standard (HASS 102 1972).)
[Appendix 7]
The infection risk assessment method according to Supplementary Note 1,
Dispensing liquid particles containing ethylene glycol and water into said collective space.
[Appendix 8]
The infection risk assessment method according to Supplementary Note 1,
It discharges at least 50 mg/m ³ of said liquid particulates into said collective space.
[Appendix 9]
The infection risk assessment method according to Supplementary Note 1,
After discharging the liquid particles into the collecting space, the time until the number of particles of the liquid particles decreases to 1/100 of the maximum value of the number of particles of the liquid particles or within 60 minutes, whichever is shorter Tracking the number of liquid particulates over time.
[Appendix 10]
The infection risk assessment method according to Supplementary Note 1,
The infection risk is the risk of aerosol infection caused by an aerosol containing the new coronavirus,
To assess the risk of aerosol infection of the new coronavirus infection (COVID-19) in the gathering space.
[Appendix 11]
The infection risk assessment method according to Supplementary Note 1,
The collective space is not a space exclusively used by employees, but a customer-use space accessible by customers or customers and employees.
[Appendix 12]
An infection risk reduction method for reducing the risk of infection of an infectious disease in a gathering space inside a facility,
Evaluate the aerosol infection risk of the collective space by the infection risk assessment method according to Appendices 1 to 11,
If the risk of aerosol infection in the gathering space is evaluated to be high, remedial measures will be taken until the fine particle removal capacity becomes equal to or higher than the required ventilation capacity.
[Appendix 13]
The infection risk reduction method according to Supplementary Note 12,
As the improvement measures, ventilation by opening windows, doors or vents; operation of ventilation fans, total heat exchangers, air conditioners, circulators or air cleaners; installation of shielding plates or partitions; reduction of accommodation capacity; Those that apply at least one selected action.

<Supplement>
- The liquid particulates in Appendices 1 to 13 may be particulates other than liquid. A mixture of liquid particles and solid particles may also be used. That is, the liquid particles in Appendices 1 to 13 may be replaced with solid particles, or may simply be referred to as particles as a general expression.

≪5. Evaluation device and evaluation program for aerosol infection risk≫
Next, the aerosol infection risk evaluation device 50 (hereinafter simply referred to as the evaluation device 50) of the present embodiment will be described in order of the configuration and function, operation and effect of the evaluation device 50 with reference to the drawings.

<Structure and function of the evaluation device of the present embodiment>
FIG. 30 is a block diagram of the evaluation device 50 of this embodiment. The evaluation device 50 includes an emission source 60 (an example of an emission unit), a particle counter 70 (an example of an identification unit), a control device 80 (an example of a control unit and an evaluation unit), and a report creation unit 90 (an example of a creation unit ) and

[Emission source and particle counter]
The emission source 60 is arranged in a space having a defined volume (for example, the gathering space described above) and has a function of emitting a plurality of fine particles into this space. Emission source 60 may be, by way of example, a machine that emits a plurality of particulates, such as a commercially available smoke machine. Further, the type of particles emitted from the emission source 60 may be liquid particles, solid particles, or a mixture thereof.

The particle counter 70 measures the number of the plurality of particles in this space a plurality of times, and compares the elapsed time from the end of emission of the plurality of particles by the emission source 60 to the measured number of the particles. It has a function of deriving a specific elapsed time until the number of the plurality of particles decreases to a predetermined quantity from the relationship, and specifying the ability to reduce the plurality of particles in the space from the specific elapsed time.
Here, the "predetermined number" means the number that is 1/100 the number measured as the maximum number of the plurality of liquid particles present in the air in the collection space after the discharge step. ” means. Along with this, the "specific elapsed time" means the time corresponding to the recovery time t1.

〔Control device〕
The control device 80 has, as shown in FIG. 30 , an arithmetic section 82 (another example of a control section, an example of an evaluation section), an input section 84 , a storage section 86 and an output section 88 .
The input section 84 has a function of receiving an input signal from an external device. In this embodiment, as an example, the emission source 60 and the particle counter 70 correspond to external devices. The output unit 88 has a function of outputting to the outside the result of the arithmetic processing applied by the arithmetic unit 82 to the data input to the control device 80 . In this embodiment, as an example, the report creation unit 90 corresponds to an external device, and the result is obtained by applying arithmetic processing to the data input to the input unit 84 using the program P described later by the arithmetic unit 82. Corresponds to the output data.
The calculation unit 82 has a function of performing calculation processing based on a program P (aerosol infection risk evaluation program) described later, and components other than the calculation unit 82 in the control device 80, the emission source 60, the particle counter 70, and the report creation unit. It has a function to control 90.
The storage unit 86 has a function of storing the program P and the result calculated by the calculation unit 82 .
Note that the algorithm of the program P and the content of the arithmetic processing of the arithmetic unit 82 will be explained in the explanation of the operation of the evaluation device 50, which will be described later.

[Report Creation Department]
The report creation unit 90 has a function of creating a report of the evaluation result evaluated by the control device 80 and information accompanying the evaluation result. The contents of the report will be explained in the explanation of the operation of the evaluation device 50, which will be described later.
Note that the evaluation device 50 of the present embodiment is provided with the report creation unit 90 as an example. can be done. From this point of view, the report creation unit 90 may be omitted.

<Operation of the evaluation device of the present embodiment (method for evaluating aerosol infection risk)>
Next, the operation of the evaluation device 50 of the present embodiment (the aerosol infection risk evaluation method S100 of the present embodiment) will be described with reference to FIGS. 30 and 31. FIG.
FIG. 31 is a flowchart of an aerosol infection risk evaluation method performed using the evaluation device 50 of the present embodiment. The method for evaluating the risk of aerosol infection according to this embodiment includes the following multiple steps.

＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
・Release step S10
・Specifying step S20
- Step S30 of judging whether the reduction capacity is equal to or greater than the required ventilation capacity (judgment step S30)
・Evaluation step S32 for evaluating that there is no risk of infection (positive evaluation step S32)
・Evaluation step S34 for evaluating that there is an infection risk (negative evaluation step S34)
・Report creation process S40
＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝

The contents of each of the above steps will be described below. It is realized by

[Release step S10]
The method for evaluating the risk of aerosol infection of this embodiment starts from the release step S10. The release step S10 is a step in which the release source 60 arranged in a space having a defined volume releases a plurality of fine particles into the space. Specifically, the calculation unit 82 of the control device 80 operates the emission source 60 so that the emission source 60 arranged in the space to be evaluated emits a plurality of particles into the space for a predetermined period. . This process ends when a state in which a plurality of fine particles are contained in the space is formed.
It should be noted that the number of the plurality of fine particles released into the space conforms to the case of the above-described plurality of embodiments.

[Specifying step S20]
The specifying step S20 is a step performed after the release step S10 is completed. In the specifying step S20, the number of the plurality of particles is measured multiple times in the space where the plurality of particles are emitted in the emission step S10, and the elapsed time from the end of the emission of the plurality of particles by the emission source 60 is determined. A specific elapsed time until the number of the plurality of particles decreases to a predetermined number is derived from the relationship with the measured number of the plurality of particles, and the plurality of particles in the space is calculated from the specific elapsed time This is the step of identifying the ability to reduce the This process is performed by the particle counter 70 controlled by the calculation unit 82 . Here, the predetermined number is, for example, 1/100 of the number measured as the maximum number of the plurality of liquid particles present in the air of the space after the discharge step S10. . Further, the specific elapsed time is, for example, the time until the number measured as the maximum number of the plurality of liquid particles present in the air in the space after the discharge step S10 is reduced to 1/100. It corresponds to the elapsed time (that is, the aforementioned recovery time t1). The ability to reduce a plurality of particles in space is a value specified from a specified elapsed time. The longer the recovery time t1, the lower the reduction capability.
After the particle counter 70 identifies the reduction ability, this process is completed when the data of the reduction ability is stored in the storage unit 86 via the input unit 84 .

[Determination step S30, positive evaluation step S32, and negative evaluation step S34]
The determination step S30 is a step performed after the identification step S20, and is a step of determining whether the reduction capacity is equal to or greater than the required ventilation capacity. The positive evaluation step S32 and the negative evaluation step S34 are respectively steps performed after the determination step S30. In the positive evaluation step S32, when a positive determination is made in the determination step S30, that is, when it is determined that the reduction capacity is equal to or greater than the required ventilation capacity, a positive evaluation (no (or low) risk of aerosol infection) is made. It is a process to do. On the other hand, in the negative evaluation step S34, when a negative determination is made in the determination step S30, that is, when it is determined that the reduction capacity is less than the required ventilation capacity, a negative evaluation (there is a risk of aerosol infection (or high)).
This process ends when the calculation unit 82 makes a comparison using the data on the reduction capacity and the data on the required ventilation capacity stored in the storage unit 86 to determine whether the evaluation is positive or negative.

[Report creation step S40]
The report creation step S40 is a step performed after the positive evaluation step S32 or the negative evaluation step S34. In the report creation step S40, the report creation unit 90 creates a report including the evaluation result evaluated by the control device 80 (calculation unit 82) and information accompanying the evaluation result. Here, as an example, the report of information accompanying the evaluation result includes any of the following contents.

========================================
・Reduction capability specified in the specifying step S20 ・Regarding the relationship between the elapsed time from the end of the emission of the plurality of particles by the emission source 60 and the number of the plurality of particles to be measured, which is measured in the specifying step S20 Information (examples include tables, graphs (two-dimensional spectrum), etc.)
・When a negative determination is made in the determination step S30, information regarding the insufficient reduction capability required for evaluating that there is no aerosol infection risk in the space to be evaluated ・When a positive determination is made in the determination step S30 , information on the extra capacity of the reduction capacity required to assess that there is no risk of aerosol transmission in the space under assessment ===================== ====================

The report creation unit 90 is, for example, a display device such as a display, a printing device such as a printer, a transmission device that transmits a report to an information terminal used by a user via a network, or other devices.
This process ends when the report creation unit 90 creates the report. In addition, the evaluation method S100 of the aerosol infection risk of the present embodiment ends when the report creation process ends.

[Algorithm of Program P]
The algorithm of the program P is an algorithm for realizing the operation based on the flowchart of FIG. 31, which is an example for executing the aerosol infection risk evaluation method S100 of this embodiment.

<Effects of the evaluation device of the present embodiment>
Next, the effects of the evaluation device 50, the evaluation method, and the program P of this embodiment will be described.
The aerosol infection risk evaluation method S100 of the present embodiment easily evaluates whether there is an aerosol infection risk in a space having a predetermined volume by specifying the reduction ability obtained from the reduction speed of a plurality of fine particles. can do.
In addition, the aerosol infection risk evaluation method S100 of the present embodiment can inform the user of the reduction ability by a report created using the report creation unit 90 .
In addition, the aerosol infection risk evaluation method S100 of the present embodiment visualizes the relationship between the elapsed time from the end of the step of releasing the plurality of particles and the number of the plurality of particles to be measured, using the created report. to let the user know.
In addition, the evaluation method S100 of the aerosol infection risk of the present embodiment, when evaluating that there is an aerosol infection risk in a space by the report creation function of the report creation unit 90, determines the lack of the reduction capability in the space. User can be notified.
In addition, the evaluation method S100 of the aerosol infection risk of the present embodiment, when evaluating that there is no aerosol infection risk in the space by the report creation function of the report creation unit 90, reduces the extra capability of the reduction capability in the space. User can be notified.
In addition, the aerosol infection risk evaluation program (program P) of the present embodiment allows a computer (evaluation device 50 as an example) to easily evaluate whether there is an aerosol infection risk in a space having a specified volume. can be made

≪6. HACCP type aerosol infection risk assessment device and assessment program»
Next, referring to FIG. 32 for a HACCP type aerosol infection risk evaluation device (hereinafter referred to as a HACCP type evaluation device), which is a modification of the aerosol infection risk evaluation device 50 of the present embodiment, the HACCP type evaluation device , HACCP type evaluation device configuration and function, operation and effect will be described in this order. In the following description, only points different from the evaluation device 50 described above will be described. Also, in the following description, it should be noted that the same reference numerals are used for the components having the same functions as the components of the present embodiment described above.

<Purpose of creating HACCP type evaluation device>
HACCP is an abbreviation for Hazard Analysis and Critical Control Point. Food business operators themselves must identify hazards such as contamination with food poisoning bacteria and contamination with foreign matter, and then conduct all processes from the arrival of raw materials to the shipment of products. It is a method of hygiene control to control particularly important processes in order to remove or reduce these hazards in the process and to ensure the safety of products. In other words, HACCP is a technique for hygiene control in the field of food and the like.
The required ventilation capacity explained so far is simply based on the criteria determined by taking into consideration the volume of the space, but originally, the ventilation capacity required for the same volume of space varies depending on how the space is used. considered to be different. For example, even if a concert is held with 1,000 people gathered in the same volume of space, there will be differences between the hard rock concert and the classical music concert. Clearly, there can be large differences in the amount of droplets generated in the space.
Therefore, Tetsuya Mizuno, the inventor of the present application, believes that incorporating the concept of HACCP into sanitation management in the environmental field will be a true method of environmental sanitation management. Created an evaluation program.

<Functions, configuration and operation of HACCP type evaluation device>
In this modified example, the differences from the above-described embodiment are as follows. That is, the evaluation flow (HACCP-type aerosol infection risk evaluation method S100A) in FIG. S5) is replaced with the determination step S30 of the aforementioned evaluation flow (see FIG. 31) (see determination step S30A).
As a result, for example, if the required ventilation capacity to be evaluated has a value of Q, for example, if the gathering space is for a concert such as hard rock, the value will be 5 x Q based on past evaluation results, etc. At a concert, the value may be 0.3×Q based on past measurement results. Here, each of the "5x" and "0.3x" parts is a weighting factor determined by the utilization mode of the collective space. It may be stored in the storage unit 86 . In addition, the weighting factor is also caused by the use state of the masks of the users who use the collective space, the utterance intensity (how loud the user speaks), and the like. Therefore, these may be varied according to the results of measurement.

<Effects of HACCP-type evaluation equipment, etc.>
According to this modified example, it is possible to evaluate the aerosol infection risk more appropriately.

≪7. Air purification system≫
Next, an air cleaning system 55 having the evaluation device 50 of the above-described embodiment (however, the report creation unit 90 may be omitted) as a component will be described. That is, multiple types of air cleaning systems will be described here.

<Air cleaning system of the present embodiment>
The air cleaning system 55 of this embodiment will be described below with reference to FIGS. 33 to 35. FIG.

[Functions, configuration and operation of the air cleaning system of the present embodiment]
FIG. 33 is a block diagram of the air cleaning system 55 of this embodiment. Moreover, FIG. 34 is a schematic diagram of the air cleaner 95 of the present embodiment. The air purification system 55 of this embodiment includes the evaluation device 50 of this embodiment (however, the report creation unit 90 may be omitted), the air purification device 95, and the notification device AD (an example of the notification unit). ing. The air cleaning device 95 and the notification device AD are communicably connected to the evaluation device 50 as shown in FIG. The air purification system 55 has a function of evaluating the risk of aerosol infection by the evaluation device 50 and a function of purifying the air in the space by the air purification device 95 . Furthermore, the air purification system 55 has a function of maintaining a state in which there is no aerosol infection risk in the space based on the evaluation result of the aerosol infection risk by the evaluation device 50 .

<Air purifier>
FIG. 35 is a flowchart of an aerosol infection risk evaluation method S100B performed using the air purification system 55. FIG.
The air cleaner 95, as shown in FIG. 34, has a fan 95A (an example of an air blowing source), a filter 95B (an example of a trap), and a housing 95C. An intake port 95D and an exhaust port 95E are formed in the housing 95C.
The fan 95A has a function of drawing air into the intake port 95D and exhausting air from the exhaust port 95E. In other words, the fan 95A has a function of sucking the air in the space into the housing 95C through the intake port 95D and exhausting it into the space through the exhaust port 95E. Furthermore, since the air purifier 95 is communicably connected to the evaluation device 50, the fan 95A, when the control device 80 makes a negative determination in the determination step S30 and advances to the negative evaluation step S34, the calculation unit 82 Alternatively, it has a function to be controlled by a control device (not shown) of the air cleaning device 95 to increase the number of revolutions and blow more air. Further, when the control device 80 makes an affirmative determination in the determination step S30 and proceeds to the affirmative evaluation step S32, the fan 95A is controlled by the calculation unit 82 or the control device (not shown) of the air cleaning device 95, and the rotation speed is reduced and has the ability to blow less air. In this way, the air cleaning system 55 of the present embodiment can maintain a state in which there is no aerosol infection risk in the space by controlling the number of rotations of the fan 95A to increase or decrease.

<Notification device>
When the control device 80 (the calculation unit 82) evaluates that there is an aerosol infection risk in the space, the notification device AD makes a negative determination in the determination step S30 and proceeds to the negative evaluation step S34. If so, it has a function of notifying the user of the fact in the reporting step S45. The notification device AD may be, for example, a light emitting device, a speaker, a monitor, or the like, or may be a transmission device or other device that transmits information to an information terminal used by a user via a network or the like. As a result, the notification device AD should be able to notify the user that there is an aerosol infection risk in the space.

<supplement>
Here, the air cleaning system 55 of the present embodiment performs the aerosol infection risk evaluation method S100B (see FIG. 35), for example, by providing a timer (not shown) in the control device 80 and performing it periodically. You may do so. Alternatively, the user may send an instruction through a user interface (not shown).
Also, the air cleaning device 95 may have one or both of the humidifying function and the temperature adjusting function. In particular, when the air purifier 95 has a humidifying function, evaluation may be performed by mixing a plurality of fine particles into steam released into the space together with the humidified air.

[Effects of the air cleaning system of the present embodiment]
Next, the effect of the air cleaning system 55 of this embodiment will be described.
The air purification system 55 of the present embodiment can automatically reduce the risk of aerosol infection when evaluating that there is a risk of aerosol infection in the space.
Further, when the air cleaning system 55 of the present embodiment evaluates that there is a risk of aerosol infection in the space, it can inform the user of that fact.
In addition, the air cleaning system 55 of the present embodiment can exhibit one or both of a humidifying function and a temperature adjusting function as well as an air cleaning function that reduces the risk of aerosol infection. In particular, when the air cleaning device 95 is provided with a humidifying function, the air cleaning device 95 can be provided with the function of the emission source 60 . That is, it is effective in that the emission source 60 becomes unnecessary.

≪8. Variation≫
As described above, the present invention has been described using a plurality of embodiments and examples, but the present invention is not limited to these embodiments and the like. For example, the technical scope of the present invention also includes the following modes.

For example, the evaluation device 50 described above determines whether the reduction capacity is equal to or greater than the required ventilation capacity in the determination step S30 (see FIGS. 30 and 31). Any one of the infection risk evaluation method to the fourth infection risk evaluation method may be performed. Alternatively, two or more of these evaluations may be evaluated, and if the result of one of the evaluations is positive, it may be evaluated that there is no risk of infection. Also, for example, two or more of these evaluations may be evaluated, and if all the evaluation results are positive, it may be evaluated that there is no risk of infection. In this case, the evaluation criteria can be strict. For example, if the evaluation criteria are not clear for new viruses that will occur in the future, the latter evaluation will make it easier to ensure safety risks.

Further, for example, the air cleaning system 55 described above adjusts the amount of air blown by the fan 95A (see FIGS. 33 and 34), but the air cleaning device 95 may be configured as follows. Specifically, the filter 95B is, for example, a plasma cluster type dust collecting mechanism (not shown, an example of a trap). Alternatively, the air purifier may control the plasma cluster type dust collection mechanism so that the plasma cluster type dust collection mechanism captures many of the plurality of fine particles.

Further, for example, in the description of the present embodiment, the subject of evaluation is the risk of aerosol infection, but the present embodiment can also contribute to the evaluation of risks other than the risk of aerosol infection. For example, dust damage risk may also be used as a dust damage risk evaluation method, evaluation device, and evaluation program.

The infection risk evaluation method of the present embodiment can be used, for example, to evaluate the infection risk of infectious diseases in spaces such as cafeterias, restaurants, pubs, cafes, clubs, bars, karaoke boxes, concert venues, etc., reduce the risk of infection, reduce dust It can be used in work spaces where there is a risk of damage.

Currently, for facilities similar to those where clusters have occurred, and related industries, even if sufficient infection control measures are taken, requests for shorter working hours and closures are uniformly made without evaluating individual facilities. Such countermeasures cause reputational damage and economic losses, and are a factor in the impoverishment of society as a whole. According to the infection risk evaluation method and infection risk reduction method of the present invention, it is possible to easily and objectively evaluate whether a specific facility is taking infection prevention measures. It will also be possible to make rational judgments and measures such as canceling requests for business closures, etc.

The above-mentioned required ventilation capacity and corrected required ventilation capacity are criteria for determining whether or not there is an infection risk from the reduction capacity identified in the specific process. Therefore, it should be noted that in the claims of the present application, the required ventilation capacity and the corrected required ventilation capacity are specified under the generic name of reduced reference capacity.

1 Laboratory 2 Smoke machine 4 Multiple liquid particles 6 Particle counter 8 Ventilation fan 10 Air conditioner 12 Window 14 Window 16 Door 18 Installation table 50 Evaluation device 55 Air cleaning system 60 Release source 70 Particle counter 80 Controller 82 Operation unit 84 Input Unit 86 Storage unit 88 Output unit 90 Report creation unit 95 Air purifier 95A Fan 95B Filter 95C Housing 95D Intake port 95E Exhaust port 101 Hall 102 Table 104 Chair 106 Particle counter 108 Ventilation fan 109 Ventilation fan 110 Air purifier 112 Total heat exchange Device 114 Air conditioner 116 Entrance 201 Semi-private room 202 Table 204 Chair 206 Particle counter 216 Sliding door 216A Crosspiece 220 Wall 222 Wall 226 Wall 228 Wall 224 Window 220A Transom 226A Transom 228A Transom 301 Semi-private room 302 Table 304 Chair 306 Particle counter 314 Air conditioner 316 Sliding door 322 Wall 322A Transom 408 Ventilation fan 410 Air purifier 412 Total heat exchanger 414 Air conditioner 416 Sliding door 424 Window S100 Evaluation method S100A Evaluation method S100B Evaluation method S10 Release step S20 Identification step S30 Judgment step S30A Judgment step S32 Positive evaluation step S34 Negative evaluation Process S40 Report creation process S45 Report process AD Notification device P Evaluation program

Claims (9)

a releasing step of releasing a plurality of fine particles having an average particle diameter of 10 μm or less into a space having a predetermined volume so that the amount in the space is at least 50 mg/m ³ ;
After the releasing step, the number of the plurality of fine particles is measured a plurality of times in the space, and the number of the plurality of fine particles is determined based on the relationship between the elapsed time from the end of the releasing step and the number of the measured plurality of fine particles. an identifying step of deriving a specific elapsed time until the quantity of the particles decreases to a predetermined quantity, and identifying the ability to reduce the plurality of particles in the space from the specific elapsed time;
an evaluation step of evaluating that there is an aerosol infection risk in the space when the reduction capability is less than the standard reduction capability required for the space;
A method for assessing the risk of aerosol infection, including In the evaluation step, if the reduction ability is equal to or higher than the reference reduction ability, evaluate that there is no aerosol infection risk in the space;
The method for evaluating the risk of aerosol infection according to claim 1. The reference reduction capacity is a required ventilation capacity required for the volume of the space or a corrected required ventilation capacity obtained by correcting the required ventilation capacity based on the usage mode of at least one or more users who use the space.
The method for evaluating aerosol infection risk according to claim 1 or 2. a creating step of creating a report including the reduction capability identified in the identifying step;
The method for evaluating aerosol infection risk according to claim 3, further comprising the creating step creates the report further including information about the two-dimensional spectrum of the relationship;
The method for evaluating aerosol infection risk according to claim 4. to the computer,
a release function that releases a plurality of fine particles having an average particle size of 10 μm or less into a space having a predetermined volume so that the amount in the space is at least 50 mg/m ³ ;
After the emission of the plurality of microparticles is completed, the number of the plurality of microparticles is measured multiple times in the space, and the elapsed time from the termination of the emission of the plurality of microparticles is the measured number of microparticles. A specific function of deriving a specific elapsed time until the quantity of the plurality of particles decreases to a predetermined quantity from the relationship with the quantity, and identifying the ability to reduce the plurality of particles in the space from the specific elapsed time When,
Evaluate that there is an aerosol infection risk in the space when the reduction capacity is less than the reduction standard capacity required for the space, and in the space when the reduction capacity is equal to or higher than the reduction standard capacity an evaluation function that evaluates that there is no aerosol infection risk in
An aerosol infection risk assessment program that runs measuring the number of a plurality of fine particles having an average particle size of 10 μm or less emitted in a space having a predetermined volume so that the amount in the space is at least 50 mg/m ³ , Deriving a specific elapsed time until the number of the plurality of particles decreases to a predetermined number from the relationship between the elapsed time from the end of the release of the particles and the number of the plurality of particles measured, an identifying unit that identifies the ability to reduce a plurality of particles in the space from the specific elapsed time;
Evaluate that there is an aerosol infection risk in the space when the reduction capacity is less than the reduction standard capacity required for the space, and in the space when the reduction capacity is equal to or higher than the reduction standard capacity an evaluation unit that assesses that there is no risk of aerosol infection in
A control unit that controls the identification unit and the evaluation unit based on the aerosol infection risk evaluation program according to claim 6 ;
An apparatus for evaluating aerosol infection risk. a release unit disposed in a space having a predetermined volume and releasing a plurality of fine particles having an average particle size of 10 μm or less into the space so that the amount of the fine particles in the space is at least 50 mg/m ³ ;
The number of the plurality of fine particles is measured multiple times in the space, and the number of the plurality of fine particles is measured based on the relationship between the elapsed time from the end of the emission of the plurality of fine particles by the emitting unit and the number of the measured plurality of fine particles. a specifying unit that derives a specific elapsed time until the number of particles in the space decreases to a predetermined quantity, and specifies the ability to reduce a plurality of particles in the space from the specific elapsed time;
an evaluation unit that evaluates that there is no aerosol infection risk in the space when the reduction capability is equal to or higher than the reduction standard capability required for the space;
A control unit that controls the release unit, the identification unit, and the evaluation unit based on the aerosol infection risk evaluation program according to claim 6 ;
An apparatus for evaluating aerosol infection risk. a creation unit that creates a report of the evaluation result evaluated by the evaluation unit and information accompanying the evaluation result;
The aerosol infection risk evaluation device according to claim 7 , further comprising:

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