Ventilation & Filtration Recommendations

We know that ventilation and filtration are critical to mitigating risk within indoor spaces, especially given airborne transmission.  Adequate (and therefore quiet) heating and cooling also matter, since they affect the distance and volume at which staff and children can communicate.  These systems, as well as enhanced ventilation to mitigate aerosol transmission, are good in some schools and classrooms but absent, poor and/or broken in others. No indoor spaces should be open to students until they have high quality ventilation of at least 5 air exchanges per hour, demonstrated by testing within rooms, not simply modeled.