1/ The pdf link that was posted by @CDC on 2/12/21 appears no longer available. The Director of CDC was on @MeetThePress today and referred to the 5 mitigation measures for schools. She was not asked to explain blatant omissions. Incredibly disappointing & irresponsible. https://twitter.com/CorsIAQ/status/1360428143014600704

2/ The 5 major mitigation steps do NOT include reductions in virus-laden aerosol particles by increased ventilation, improved room filtration by HEPA filtration or improved centralized filtration where increasing ventilation not possible. Incredibly disappointing & irresponsible.

3/ According to CDC, only masks, 6 ft distance, surface cleaning, & testing matter. Anemic and a clear admission that @CDC still does not believe in transmission by aerosols beyond 6 ft. If you dig far enough into CDC website you'll find "ventilation".

4/ But guidance on ventilation is vague (at best) & implies lack of understanding or lack of importance. Zilch on portable HEPA filtration, which can significantly increase equivalent ventilation rate where increased ventilation is difficult. Incredibly disappointing.

5/ We ought to have a multi-disciplinary effort to do this right. @CDC is getting 1/2 of this right. It's abundantly clear that they need a lot of help on the other half. I had hope for moving forward. We are not. Incredibly disappointing.