DUBAI, UAE, 17 May 2022: Daikin Industries, parent company of Daikin Middle East and Africa, in collaboration with Osaka University’s Research Institute for Microbial Diseases[1], has tested and confirmed the effectiveness of the Flash Streamer technology against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants[2].

Making the announcement through a Press release, Daikin said:

• The research confirmed that the Flash Streamer technology inactivates SARS-CoV-2 variants more than 99.9% against the Alpha, Beta, Gamma and Omicron variants, and 99.8% against the Delta variant after four hours of exposure to Streamer discharge when compared to without Streamer.
• This means the Flash Streamer technology can be used to improve Indoor Air Quality (IAQ), when the air is contaminated with these respiratory viruses.

Daikin, calling itself as a specialist in IAQ management, said it sees it as its mission to create comfortable and sustainable interior environments. Daikin said it not only develops new technologies but also continuously verifies the effectiveness of its technologies and their importance for solving societal challenges, such as the COVID-19 pandemic.

Streamer Discharge

Daikin said its unique air purification Flash Streamer technology was developed in 2004, and since then, Daikin has conducted tests on its effectiveness with many public research institutes around the world. Following these tests, it has been confirmed that the Flash Streamer technology inactivates over 60 types of harmful substances, such as bacteria, allergens and viruses, including the influenza virus, RSV and murine noroviruses, Daikin claimed. In July 2020, the inactivation effect against the SARS-CoV-2 strain isolated in the early stages of the pandemic had also been confirmed, Daikin further said.

Osaka University, which Daikin commissioned to test the effectiveness of the Flash Streamer technology against variants of the SARS-CoV-2, proved that the Flash Streamer technology inactivates the Alpha, Beta, Delta, Gamma and Omicron variants, Daikin said.

Takashi Namikawa, Senior Engineer of Daikin’s Technology and Innovation Center for this project, said: “I am delighted that Daikin’s unique air purification Flash Streamer technology has been proven effective in inactivating coronavirus (SARS-CoV-2) variants, including the Omicron variant. It shows that the Flash Streamer technology has the potential to be applied to solve societal issues further improving the quality of indoor air in schools or offices. This is very significant study for Daikin and for society.”

Daikin said it holds its mission to help people to breathe easy in high regard, as clean and quality air provides a direct correlation to a healthier, more productive and fulfilled life. Daikin said its latest brand campaign, “Breathe Health” reinforces the importance of equal access to quality air regardless of location.

• Experimental Results: Irradiation with Streamer discharge for four hours inactivated more than 99.9% of the Alpha, Beta, Gamma and Omicron variants and 99.8% of the Delta variant of SARS-CoV-2, compared to without Streamer discharge. 
• Evaluation method: In the verification test, hCoV-19/Japan/QHN002/2020 strain (Alpha variant), hCoV-19/South Africa/KRISP-EC-K005321/2020 strain (Beta variant), hCoV-19/Japan/TY7-503/2021 strain (Gamma variant), hCoV-19/USA/PHC658/2021 strain (Delta variant) and hCoV-19/Japan/ TY38-873/2021 strain (Omicron variant) were used. Two acrylic boxes of about 31 litres were prepared, and a Streamer discharge device was installed in one of the boxes. Six-well plate with 0.5 ml/well of virus solution were placed on Seesaw shaker in both boxes. Streamer irradiation was performed with shaking. After 1, 2, and 4 hours, the virus solution was collected, and the virus titer was measured by TCID₅₀ using Vero E6/TMPRSS2 cells.
• Flash Streamer technology: The Flash Streamer technology is a technology that uses Streamer discharge, which Daikin developed in 2004, to perform oxidative decomposition of harmful substances. It is a type of plasma discharge featuring an innovative air purification technology that stably generates high-speed electrons. When combined with air components, these high-speed electrons have a capability for powerful oxidative decomposition, and this capability enables Streamer discharge to continuously remove odors, bacteria and indoor air pollutants such as formaldehyde.

In addition to above viruses, the effectiveness against 7 types of bacteria such as Legionella and Pseudomonas aeruginosa, 30 types of allergens such as cedar pollen and Dermatophagoides farinae (excrement/carcass), and 19 types of harmful chemical substances have been verified by public institutions.