Scientifically demonstrated that the use of acrylic boards is less effective for aerosol countermeasures -it is clear that it is also a loud conversation-

Matrix Co., Ltd., in research with the National Institute of Technology Hachinohe College of Technology and the Aomori Prefectural Industrial Technology Center Hachinohe Industrial Research Institute, used acrylic plates as an aerosol countermeasure. Scientific data has revealed that the effect is weak.

The results of the study are as follows.

(1) Inability to prevent exhaled aerosols that are the source of infection.

(2) It is difficult to hear, which is equivalent to talking about 5 times farther for men and about 3 times farther for women.

(3) Floor-standing air purifiers cannot purify the air unless you pay attention to how they are used.

(4) Among the devices tested, only the desktop air purifier was able to prevent aerosols from reaching the face in a table environment.

In addition, we would like to report that we have verified how to use various air purifiers effectively for infection control by visualizing airflow.

[Outline]

In response to the official data of the CDC (American Centers for Disease Control and Prevention) and WHO (World Health Organization), it was pointed out that the coronavirus infection is an airborne transmission, and Matrix Co., Ltd. We would like to scientifically measure the effect of the purifier "Cyclone" on preventing the spread of aerosols in the exhaled breath that causes airborne infections. Using the product development subsidy, we conducted measurements with the Hachinohe National College of Technology and the Hachinohe Technical Research Institute.

At the same time, as our independent business, we have verified the effects of acrylic plates, which we thought were physically effective until now, but had no scientifically proven data. We also compared it with a stationary air purifier and verified how to proceed with infection control measures for infectious diseases that are strongly suspected to be airborne, such as the Omicron strain.

Measurement results are as follows.

(1) Airflow visualization experiment

●Acrylic plates are highly effective in preventing large-sized droplets that do not get on the air current from reaching the other side, but against small-sized droplets and aerosols that get on the air current, air retention and There is a high possibility that there will be a flow around from the side, and the risk of infection may increase unless the environment considers the air current.

● Matrix Corporation's desktop air purifier "Cyclone" forms an air curtain directed vertically upwards. The flow velocity from the spout is about 4m/s, and the upward velocity reaches 1.5m/s covering a width of about 1m at the position equivalent to the height of the face. Visualization also confirmed that the air emitted from the oral cavity did not reach the opposite side and was transported sufficiently upward. In addition, a planar flow toward Cyclone is formed near the tabletop, reducing the risk of contact infection, which is a concern with tabletops and acrylic plates. From the above, a high infection prevention effect can be expected without the need to physically separate the space with Cyclone.

●Observing the air flow of the floor-standing air purifier, it draws in the surrounding air from the air inlet on the wall side and discharges it upwards into the room. Depending on the environment, recirculation occurs in which the exhausted air is sucked in again, and purification of the air on the opposite side of the room may not progress. In addition, even if you inhale from the side, you can expect a purifying effect if you sit on the tatami mats and talk because the air is sucked from that height, but if you sit on a chair and talk, you can expect an immediate air purifying effect. not suitable for

When an acrylic plate is placed and an aerosol is produced

When the desk air purifier is placed and the aerosol is emitted

(2) Shielding of sound frequencies corresponding to male and female voices

●The acrylic plate reduces the frequency of sound (500Hz) corresponding to a male voice by approximately 14dB, and the sound of a frequency (1kHz) corresponding to a female voice by approximately 9dB. In comparison, it is difficult to hear, which is equivalent to talking about 5 times farther for men and about 3 times farther for women.

●When using Matrix Co., Ltd.'s Cyclone, it is almost the same as having a conversation without the acrylic plate, and there is almost no problem such as deterioration of voice.

Attenuation of sound by acrylic plate

Relationship between sound attenuation and distance

As mentioned above, it was clarified that the use of the acrylic board does not completely prevent exhaled aerosols and makes it difficult to hear conversations, which causes loud conversations.

Also, as a countermeasure against infection with air purifiers, floor-standing air purifiers are effective when the source of aerosols is low, such as in a Japanese-style room. In the case of living spaces, the effect is low, and it has been clarified that the desktop air purifier is more effective.

[About the importance of desktop air purifiers]

Different from general floor-standing air purifiers, the tabletop air purifier "Cyclone" can inhale and process exhaled aerosols more efficiently by inhaling at a position close to the human mouth and nose. Is possible.

Also, by making good use of the exhaust and creating an air curtain, we are creating a shield like an acrylic plate.

In particular, under the circumstances where the Delta and Omicron strains are prevalent, various researchers have voiced that it is difficult to deal with aerosols with acrylic plates, and I hear that there is a sense of stalemate.

While countermeasures against "airborne infections" are urgently needed, countermeasures against aerosols using tabletop air purifiers are being used in restaurants that are struggling to prevent infection, elderly people who have difficulty hearing and speaking, and mouth movements of the other party. We believe that it is very effective in preventing infection at hospitals and public facilities counters used by people with hearing loss who have difficulty communicating because they cannot see.

[Company Overview]

Trade name: Matrix Inc.

Representative: Terumasa Takamatsu, President and Representative Director

Location: 2-8-9 Waseda, Hirosaki City, Aomori Prefecture

Established: December 2015

Business description: Medical consulting Development of infection control products

Prototype development of medical equipment

URL: http://www.matrix55.jp/

http://matrix.theshop.jp/