Confirmed Inactivation Effect of Flash Streamer Technology Against Coronavirus (SARS-CoV-2) Variants

Brussels, 26^th of April 2022 – Daikin Industries, Ltd., mother company of Daikin Europe N.V., and Osaka University’s Research Institute for Microbial Diseases [1] have tested and confirmed the effectiveness of the Flash Streamer technology against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants [2].

·       The research confirmed that the Flash Streamer technology inactivates more than 99.9% of the SARS-CoV-2 Alpha, Beta, Gamma and Omicron variants, and 99.8% of the Delta variant after 4 hours of exposure to Streamer discharge compared to without Streamer.

·       This means the Flash Streamer technology can be used to improve indoor air quality when the air is contaminated with these respiratory viruses.

As a specialist in indoor air quality management, Daikin sees it as its mission to create comfortable and sustainable interior environments. Daikin not only develops new technologies, but also continuously verifies the effectiveness of its technologies and their importance for solving societal challenges such as today’s pandemic.

Daikin’s 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 mouse noroviruses. In July 2020, the inactivation effect against the SARS-CoV-2 strain isolated in the early stages of the pandemic has also been confirmed.

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

Takashi Namikawa, Senior Engineer of Daikin’s Technology and Innovation Center for this project, says: “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 such as the quality of indoor air in schools or offices. This is very significant for Daikin and for society”.

Experimental Results

Irradiation with Streamer discharge for 4 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.

Explanatory video

This video explains the main features and characteristics of Daikin patented Flash Streamer technology, the evaluation method and the test results.

To watch the video click here: Daikin Streamer Technology, Inactivation of Coronavirus, Omicron and Other Strains [DAIKIN]

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.

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.

[1] The test is conducted by Professor Tatsuo Shioda and Assistant Professor Tadahiro Sasaki for the Department of Virus Infections, Research Institute for Microbial Diseases, Osaka University.

[2] The test described herein only concerns the patented Flash Streamer technology. The effects of products equipped with the Flash Streamer technology or the effects in actual use environment may differ. For more information on the Daikin products incorporating the Flash Streamer technology, please refer to the relevant product information.

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