Sunlight appears to have “powerful” effect on killing virus, DHS says
Acting Under Secretary of Science and Technology at DHS in the US Bill Bryan said Thursday that emerging research has shown that solar light appears to have a “powerful” effect on killing the coronavirus.
The virus “dies the quickest in the presence of direct sunlight,” Bryan told reporters at the Coronavirus Task Force briefing.
According to a slide shown at the daily White House Coronavirus Task Force briefing, the virus has a half life of 18 hours on a surface when it’s 70-75 degrees, with 20% humidity and no sunlight. But when the humidity rises to 80% and sunlight increases, the virus’ half life drops to two minutes.
Bryan talked about the existence on playground equipment as an example: In the sunlight, the virus would die very quickly, he said, although parts of the equipment in the shade would not be affected in the same way.
These studies may help guide governors in their decisions about what to open and when, Bryan added.
Bryan also said that bleach kills the virus in about five minutes, while isopropyl alcohol takes just 30 seconds.