How can we make the return to kindergarten or elementary school safer during the pandemic? Ventilate, filter and humidify to optimal levels.
BASED ON WHAT WE KNOW about the coronavirus, no child will be 100 percent safe going back into an enclosed classroom in the U.S., even if PPEs and social distancing rules are strictly followed. Enclosed spaces without proper ventilation create ideal conditions for coronavirus spread.
In fact, the World Health Organization has just been accused in a letter signed by 200 scientists of downplaying coronavirus infection risks due to airborne virus particles. Linsey Marr, a virus specialist and one of the scientists who signed the letter, told the New York Times that "the WHO had relied on studies from hospitals that suggested low levels of virus in the air. This underestimated the risk, she said, because in most buildings “the air-exchange rate is usually much lower, allowing virus to accumulate in the air.” For a deeper dive, this article in The Atlantic looks at studies of how the virus spread indoors in Japan, and has some good insights.
The same is true of most school classrooms. They're not designed for rapid air changes. That needs to be remedied before we put children at risk.
Why? Because of the way the Covid-19 virus infection works. Particles need to achieve a critical mass before successfully infecting a host, a scenario most likely when air is static and dry, and particles are being introduced repeatedly. And, while masks and good hygiene definitely reduce transmission rates, airborne control of virus spread is at least as important, especially for young children, who may not be capable of consistent social isolation. These key healthy air qualities include humidity levels, speed or air exchange, filters and virus-killing lights.