The new normal must be extreme airborne mitigation everywhere. Air quality experts need to be front and center. Imagine we had a new measles virus that caused brain damage and vaccines and natural immunity did not prevent infection.
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HVAC mechanical engineers (who are responsible for ventilation) have a basic understanding of air quality, but know very little about airborne virus mitigation. The last virus people assumed was airborne was the measles and that hasn't been a societal threat since the '60s.
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Most are unaware that electronic air cleaning doesn't work. Almost none have ever heard of upper room UVGI. We need indoor air quality standards. Air quality experts need to lead the way. Failing to emphasize that #COVIDisAirborne is preventing that.
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Addendum (twitter needs and edit option). Measles is still a big problem in developing countries. Failing to vaccinate the world hurts everyone.
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- Not enough focus on ventilation and filtration.
- Delay in acknowledging COVID is airborne
- Lack of clear communication
- Ventilation reduces risk of transmission
- look for HEPA filters and places with CO2 levels < 800 ppm
- We need operation warp speed for clean indoor air. I credited @j_g_allen for this in the interview.
(I don't believe "people will die from other respiratory viruses" was my quote)
I want to do a few tweets about common ventilation issues, but first I need to do an intro to the basic system - the RTU. It's essentially a home furnace with dampers. Here's what they look like:
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This is a schematic of what it looks like inside. Here are the steps:
1. Air is returned from the space into the unit. 2. The exhaust damper - air leaves here. It's usually a backdraft damper. Air can only flow out and not in. It isn't motorized.
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3. The mixed air dampers/economizer - these control the ventilation. When they are "open", it means the outdoor air damper is open and the return air damper is closed. This brings in 100% outdoor air. The return damper closing forces the air out through the exhaust damper.
How did he get membership to ASHRAE? Between being a doctor, MPH with specialty in pulmonary medicine and associate prof, he got an engineering degree with 12 years HVAC experience? It's not listed anywhere. (I'm an associate member because I only have 11 years experience).
I'm amazed that this concept exists. It's as if some doctors have pledged eternal loyalty to the vaccine and any additional measures are a form of adultery. It's absurd. Stop encroaching on engineering.
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An engineer's perspective:
a. Especially with boost, vaccines are extremely effective against severe disease.
b. They are not effective long-term in preventing infection.
Because of this, many have said that only severe disease matters. It's not true. Here's why:
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1. We've tried using a vaccine only approach. It's failed in every country that attempted it. 2. What about the immunocompromised, elderly and unvaccinated? 3. A vaccine only approach causes people to blame the pandemic on the unvaccinated. This can't continue.
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A UV light is placed in the duct or by the coil of an air handling unit. It will kill virus particles being supplied to the zone.
I'm not in favor:
a. It can damage the filters
b. Better alternatives are: increasing outdoor air % and improving filtration.
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c. Transmission through ducts is long range transmission. Shared room transmission is much higher risk. Better to focus on higher risk.
d. People in the industry have expressed skepticism to me of how
effective this actually is.
e. UV is more expensive than filtration.