Discover and read the best of Twitter Threads about #DontShareYourAir

Most recents (1)

#COVIDCO2 readings in an Ottawa classroom. Never reached a steady state. At 3152 ppm every breath contains 7.2% of other people's breath‼️‼️ 🤮. #DontShareYourAir #Onted
Classroom has below 0.4 air changes per hour.

Target MIN: 3-4, Good: 4-5, Excel 5-6, Ideal 6+
/1
For COVID, air changes from HEPA filtration are equivalent to outdoor air. Typical classroom portable HEPA air cleaner:
400 CFM on max at 65 dB adds 2.7 ACH
200 CFM on med at 55 dB adds 1.3 ACH.
Two on med would be 58 dB.

BUT there's still the cognitive impact of 3000ppm!
/2
Here's the back-calculation assumptions used to reach 0.4 ACH in a classroom. I'm assuming 12 foot ceilings for an older naturally ventilated school. Other values are typical as well. The calculator throws an exception in red at 19 students, but not at 18.
/3
Read 10 tweets

Related hashtags

Did Thread Reader help you today?

Support us! We are indie developers!


This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3.00/month or $30.00/year) and get exclusive features!

Become Premium

Too expensive? Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal Become our Patreon

Thank you for your support!