Thread by @DrEricDing

I’m told schools are nagging Congress for more “flexibility” to spend the new $130 Bil school COVID aid $ so 🏫 can uselessly buy plexiglass & hire more janitors to disinfect surfaces—instead of prioritizing improving ventilation & air quality science.🤦🏻‍♂️🧵

2) I’m the biggest supporter of teachers and students—but school boards honestly don’t understand the science and importance of ventilation & air quality for airborne transmission! This is COVID pandemic assurance money—for truly stopping the pandemic not for “pandemic theatre”!

https://twitter.com/DrEricDing/status/1363638390432948227

3) VENTILATION is key. Both ventilation and masks needed to reduce risk indoors in schools. But most schools are not ventilated well enough.

4) Most schools don’t even achieve half the recommended 5 air exchanges per hour. @CorsIAQ says he typically sees classrooms with just 2 ACH per hour. In Arlington VA school, average was just 2.4. Many classrooms have as low as 0.5 per hour!

5) does the CDC suggest good ventilation and air cleaning like HEPA filters? Yes! But it was buried in their recent guidance.

cdc.gov/coronavirus/20…

6) To be clear, air quality improvement + ventilation are stackable together for achieving the recommended 5 ACH per hour. A good HEPA can add +3 to a background 2 natural ventilation. Or it can add +4.5 to poor 0.5 ventilation.

https://twitter.com/drericding/status/1364066778595405830

7) I’m told schools also want to use the $130 billion (~$1 mil per school, for 130k schools) to backfill their budget deficits. But THATS NOT GONNA SOLVE the pandemic and make schools safer for kids to return & STAY SAFE. Safe schools is key. Airborne transmission is real.

8) How important is ventilation outside of COVID risk? “There is compelling evidence, from both cross‐sectional and intervention studies, of an association of increased student performance with increased ventilation rates.”... onlinelibrary.wiley.com/doi/abs/10.111…

9) “The net annual costs, ranging from a few dollars to about 10 dollars per person, are less than 0.1% of typical public spending on elementary and secondary education in US. Such expenditures seem like a small price to pay given the evidence of health & performance benefits.”

10) Here is the cost breakdown of one good portable HEP filter per standard classroom, by @CorsIAQ. The total cost across 3 years is just $11/student. That is nothing compared to the cost of other school materials. And this improves learning! We need to do this & *PRIORITIZE* it!

11) it’s not impossible. President Kennedy once said, we choose to goto the moon not because it is easy—but because they are hard—and important. Some think asking for sufficient school ventilation is like asking schools to goto the moon. No, not true! It’s possible. We can do it.

https://twitter.com/DrEricDing/status/1362880620343484416

12) To be clear, what I’m advocating is prioritizing spending on ventilation, air cleaning approaches, more testing, and more/better PPEs like premium masks. And I have the support of not only aerosol scientists, but also teachers unions & parents. Stop airborne transmission!

13) Worst case, we can sometimes ventilate without HEPA filters or full windows. You can even do it with 1 door—but 2 doors better. Here is how to ventilate your school classrooms if unable to open window with 2 fans. #COVID19

14) Heck, even Biden’s own former transition COVID TASK FORCE members are demanding the CDC to better focus on airborne transmission—and emphasize premium masks, air quality, and ventilation! His own COVID task force experts! drive.google.com/file/d/1O5zd_J…

15) Do we want to be like teachers in students in Quebec 🇨🇦 where #COVID19 cases surged faster in schools than general population? Notice cases plummet during winter break and surged again after break.

https://twitter.com/drericding/status/1364399105972273155

16) How many HEPA filters do we need for a room? Well there is a science to this—aerosol environmental engineering to the rescue. See this post and thread 🧵 on how to solve the math based on the CADR rating of a HEPA filter — get a 250-300 CADR portable machine.

https://twitter.com/drericding/status/1364066139471552513

17) Also really cool cheap air cleaner is this MERV13 filter homemade device called “Corsi Box”. This fan’s air speed is 580 feet/min—so multiply by the area of the fan—to get Q. The F of these filters is 0.9 I’m told. Then you can get the CADR value for room calculation & ACH.

https://twitter.com/DrEricDing/status/1362895328459059200