DEAR PARENTS—Tell your schools—this is what we need to do ensure safe schools, both masks & *ventilation* for #COVID19.

Install CO2 monitor in every classroom to ensure air refresh sufficient

Open windows if possible

Install HEPA filters (2-4 per classroom) https://twitter.com/bwaucquez/status/1326539043039948805

2) Ventilation is key, in addition to masks.

3) Meanwhile, is investing $488 million (€500m) in improving ventilation systems in schools & public buildings to help stop the spread of #COVID19. Merkel’s govt is awarding grants of up to €100,000 each to upgrade air systems to stop transmission! https://www.theguardian.com/world/2020/sep/30/germans-embrace-fresh-air-to-ward-off-coronavirus

4) Clarify - CO2 monitors in classrooms won’t solve ventilation per se. but they are a quick way to check if ventilation in a room is adequate or not. And CO2 meters are pretty cheap. It’s not hard to install either!

5) Now that aerosol transmission of the coronavirus is established, we need to both mask and disperse aerosols quickly. Key is ventilation. Japan assumed it was airborne from the very beginning. Hence their mask culture and focus on air flow. #COVID19