1/ I hope that we have collectively learned a lot (a very long list) from this pandemic. I fear that many have not.
2/ The overwhelming obvious: Vaccines reduce risk of hospitalization and death. Reducing inhalation dose of virus-laden aerosol particles reduces risk of infection, hospitalization and death.
3/ Masks, increased ventilation, appropriate filtration all reduce inhalation dose, and therefore are important weapons in reducing risk of infection, hospitalization and death.
4/ Infrastructure to sustain healthy indoor environments is woefully inadequate in too many schools across the US.
5/ The more subtle:
Never assume away the worst-case transmission pathway without evidence, & therefore leave the public with their guard woefully down for months.
6/ There is a gargantuan need to increase and improve STEM education at all levels in the US. Wow,
has this been obvious!
7/ Science communication needs to be improved, including and understanding of how to reach audiences through the complex web of communication media available today and into the future.
8/ Solutions to complex problems cannot be driven by single disciplines. Addressing this pandemic would have been for more effective if the PH & medical communities were teamed with aerosol scientists, engineers, building scientists, communication scientists, IH, & more.
9/ Multi-disciplinary collaboration is not easy. We stress it in universities, and even then it is sometimes difficult outside of crisis situations. But innovation & solutions are catalyzed when those with different but relevant expertise work work together effectively.
10/ I hope that we practice and learn to be better at multi-disciplinary collaboration in the future. While universities often stress the importance of multi-disciplinary collaboration, we need to step-up and reimagine how we can be more effective at doing so.
This is just a start ..... the list of what we should have learned to date is very long.
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2/ My message will be clear. Stay safe. Stay focused. Learn the fundamental principles and tools of your trade as you will be able to use these to change society for the better and to help heal the planet.
3/ While you are in college, take advantage of being on such a great campus. Join student groups & get to know faculty and staff. Ask for help when you need it. We are a community and are here for each other.
1/ As a follow-up to my earlier email ....
First, the concentrations of ozone needed to disinfect indoor surfaces is significant and approach or exceed the IDLH (Immediately Dangerous to Life or Health) level. So, use of ozone should be done w/ great care, if done at all.
2/ Ozone (O3) is a moderate oxidant. It reacts with almost all indoor materials, some more than others, as well as oils that we add to or unknowingly leave behind (e.g., skin oils) on those surfaces.
3/ These reactions can (over time), lead to material degradation, e.g., brittleness of rubber seals, leaching of lead from lead-based paints, and even increased susceptibility of some materials to mold growth (research done in collaboration w/ @KerryKinney14@ut_caee ).
1/ Tomorrow is my last day @Portland_State. Will miss wonderful dean colleagues, as well as faculty, staff, & students of the Maseeh College of Engineering & Computer Science @MCECSpdx. We accomplished much TOGETHER these past 3 yrs. #ThinkBoldMCECS! #ShineBrightMCECS! Images .
Some of the most inspiring students you will find anywhere. You are giants!
1/ SARS-CoV-2 travels in aerosol particles emitted from an infected individual. You want to reduce the amount of these particles you breathe (lower inhalation dose is important). We know from decades of research that the following lower your inhalation dose of aerosol particles.
2/ Masks: The higher the quality and better the fit the less aerosol particles you inhale that came out of the respiratory system of an infected person. No rocket science here.
3/ Ventilation: The greater the amount of ventilation the lower the aerosol particle concentration that originated from an infected individual(s) in the air of indoor spaces. That means you will inhale less. No rocket science here.
1/ Rebreathed Fraction (RF) and Schools.
The rebreathed fraction of air is the fraction of air that a person inhales that came out of the collective respiratoiry systems of others in the indoor space they are in. We'd like RF to be as small as possible!
2/ RF can be calculated as
RF = (CO2in - CO2out)/CO2breath
Here CO2in is CO2 concentration in the indoor space, CO2out is the outdoor CO2 concentration, and CO2breath is the typical CO2 concentration on human breath (around 36,000 to 38,000 ppm) w/ some variation by diet, etc.
3/ Earlier in the pandemic I estimated quanta generation rates based on outbreaks & used these w/ the Rudnick-Milton model to approximate an upper-bound acceptable RF(avg) of 0.008 in a model classroom. This leads to a CO2in = 698 ppm (say 700 ppm). Well before delta variant.
1/ Hearing a lot of concern about return to campus from faculty & staff at universities across the US. I wrote about this way back in spring and summer of 2020. Here we go again. Some advice here for those in states with leaders who value science and logic.
2/ If the university is open or partially open this fall, my advice is to reverse course on loosening of risk reduction interventions (and make this clear to the campus community as soon as possible).
3/ Enforce the vaccination requirement to the extent possible. It is not possible to verify at some universities relying on attestation. In those cases, employ daily reminders and signs across campus that reinforce why universal vaccination is critical for the community.