We achieved a CT(ozone concentration(ppm) X exposure time(min) )value of 60, which can inactivate coronavirus from 1/10 to 1/100 by operating for 24 h at an appropriate ozone concentration (less than 0.1 ppm) using feedback control in the previous report. In this system, the only way to reduce the ozone concentration is the decomposition reaction of ozone in the natural world, and it was not possible to cope with the rapid increase in ozone. In this study, we investigated the reduction of ozone concentration using hydrogen. As a result, it was clarified that the concentration of ozone rapidly decreased even with about 1/100 of hydrogen’s explosion limit (about 4%).
-  “2018 Information and Communication White Paper” (Ministry of Internal Affairs and Communications) http://www.soumu.go.jp/johotsusintokei/whitepaper/ja/h30/html/nd111200.html
- Japan Society for Occupational Health: Reasons for Proposing Allowable Concentrations (2000)
- Tanaka T., Yamauchi M., Kakugawa K., Uchida T., Ishihara S., Ishihara K. Feedback control of ozone concentration in a room using an ozone generator and the Internet of Things with built-in sensor. Electrotechnica & Electronica (Е+Е), Vol. 57 (1-2), 2022, pp.24-30, ISSN: 0861-4717 (Print), 2603-5421 (Online)
- https://www.winsen-sensor.com/d/files/PDF/Semiconductor%20Gas%20Sensor/mq131-(low-concentration)-ver1 _3-manual.pdf
- Nobuharu, O., Y. Sasaki, M. Yamauchi, K. Miyazono, T. Hattori, K. Kakugawa, T. Tanaka. A simple control system for ozone gas generation and its concentration measurement. IEEJ Transactions on Fundamental and Materials, 2022, in press (in Japanese)