The goal is to make sure aerosol counts are lower. We often use the analogy of cigarette smoke building up in poorly ventilated room as a visual analogy for being in a room with an infectious (speaking) supershedder. Lower counts = lower risk. CO2 alone won’t tell you this. 1/3
Having lower PM in a room has many health benefits. People often focus only on CO2 but if you are in a room where it is difficult to increase ventilation, you have no choice but to add HEPA filtration. In this case, aerosol sensors (with size) are your only helpful metric. (2/3)
PM measurements tell you how effective your HEPA filtration is—shooting to be in upper left corner (see below). There is no question that avoiding the situation in the lower right corner lowers risk of infection. CO2 measurements alone cannot be used to assess this. (3/3)
Another point that is being missed….Many people live in regions with horrible air quality so it is not helpful to open the window or pull in more “fresh air” thru HVAC. HEPA filters plus PM sensors can assure good indoor air quality. This is an environmental justice issue. (End)
#environmentaljustice we must think about other people as we come up with solutions to improve indoor air quality.
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I simply cannot believe the number of people who are content to throw up their hands and say "let's live with this virus" when there are simple measures to clean the air that would protect everyone. (1/)
Many of these "advocates for opening" paint those of us pushing for controls as being too negative. They even go so far as to say we are harming the mental health of kids. Seriously? (2/)
We all want to open and get our lives back--but we want to do so in a safe manner. And there is a way to do it!! It is not rocket science. Let's stop making choices which help this virus spread as we have been doing. Clean the air ASAP and get vaccinated when you can. (3/)
Two pubs I helped write on the airborne transmission of SARS-CoV-2. Both have been highly read (one is ranked #21 and the other #23 overall by Altmetric). How are @cdc and @WHO continuing to ignore all evidence that #COVIDIsAirborne? science.sciencemag.org/content/368/64…
Altmetric for our Science Perspective-the most downloaded paper in @ScienceMagazine in history.
Well....first on-line lecture all done and I survived. More importantly so did the class! 100 people logged on. All very polite and kind as I bumbled my way through. The chat was so funny to read!!
The class is on aerosols--so I talked about viruses being in aerosols...the hot news topic. CDC and WHO are in disagreement about whether it is in aerosols or droplets.
Why does it matter? Aerosols will last in the air for hours and travel much further than 6 ft. The Choir practice example points to aerosols + SARS-CoV-2 being a real possibility.
Critical info and advice from expert virologist (Prof Forest Rohwer at San Diego State University):
Dear Everyone,
I hope you are all doing well. I'm writing you as a virologist and immunologist who isn't an alarmist. (1/12)
With the knowledge that we currently have, I really want to stress that nearly total quarantining is needed in San Diego at this time. The important points are: (2/12)
1) There are almost assuredly a large number of asymptomatic SARS-CoV-2 spreaders. These people don't feel sick and do not have symptoms like fever, but they can spread the virus. (3/12)
Seeing pictures of tons of people at the beaches in San Diego. Watching college students laugh and crowd into one car. I am sad and scared that so many people are not taking this shelter at home order seriously. Bottom line...they are putting all of our lives at risk. (1/3)
Maybe we should ask them if they realize 793 died yesterday in Italy alone. Why? Because people refused to take it serious until it was too late. The majority of carriers were young healthy people with no symptoms. (2/3)
Why cant we learn from other country's mistakes who are ahead of us? Right now, we are on the same path as Italy. Wise individual choices is our only hope (3/3)
The two things that would help the most right now--1) testing so people who have been around many others, traveling, or have slight symptoms will know if they should stay away, and 2) social distancing. Right now, we don't have #1 so we have to rely on #2. (1/4)
We are flying completely blind in decision making regarding public health. It is extremely important we error on the side of caution and go with #2 because that is all we have right now. (2/4)
There is large uncertainty in where we are heading but we know we are in the exponential growth phase with no idea how many poeple are walking around with COVID-19 as most have zero symptoms. We ultimately control how bad this becomes by our own actions. (3/4)