Thread by @catinthefield

A 🧵on air quality and COVID transmission risk. I have a CO2 monitor - it shows me how recycled and stuffy the air is and an idea of how risky my location is for breathing in COVID from other people. Masks are not mandated inside now, so let's see what common areas are like...

First up, hiking outdoors. Beautiful - if you can get up kunanyi/Mt Wellington do it. Baseline good air is at 451 parts per million (ppm) of CO2.

2/ (spoiler: it gets worse)

Two people in a car with closed windows sitting in stationary traffic. 2513 ppm is not good! Probably some fumes in here contributing to the high reading, but still no ventilation. If I was in a taxi I'd be asking to please open the windows to get this below 1000 ppm.

3/

The supermarket! Apologies for blurry photo - I forgot and ran back in. But look! What a lovely CO2 reading of 519 ppm! I'm nearish the door, but it was like this the whole time. Quite a large supermarket with high ceilings and probably a good aircon system.

4/

A really lovely cafe - incredible lunch. This part is a conservatory with high ceilings but no open windows. Full of people. It looks airy and safe, but really isn't so much at 1028 ppm CO2. We opted to eat outside. Opening windows would help, but will be tricky in winter.

5/

This one is surprising! This reading of 1475 ppm of CO2 was recorded in an indoor market in a large shed. Big open door. There was a pizza oven, but the reading was like this everywhere. We were almost the only ppl wearing masks. We stayed 5 minutes and left reluctantly.

6/

5 friends chatting over ice cream in a small flat - we got CO2 up to 1077 ppm CO2 over a few hours. A window was semi-open behind me. As we head into winter, we'll still try to gather, but we'll bring jumpers and keep the windows open.

7/

Flying in a plane! I flew off-peak + in a serious N95 mask with head loops. CO2 was between 1080 ppm and 2031 ppm. When flying, the air is filtered so while CO2 may be high, I expect COVID aerosols wouldn't get through. I hope...Thanks for mask mandates @VirginAustralia!

8/

Worried about @skybus_aus. Always had great service, but the CO2 reading is high at 1753 ppm. Full bus of travelers and windows cannot be opened. The website doesn't mention air filtering. I think this 20-minute journey is the riskiest part of travel.

9/
#COVIDisAirborne

If you're trying to avoid catching COVID (or passing it on unknowingly) avoid places with bad ventilation and wear a quality mask indoors. Businesses - follow @RobynSchofield3 and @CleanAirStars who are calling for COVID safe air.

10/
pursuit.unimelb.edu.au/articles/which…

Finally, why bother? Well, COVID would be really bad for me as an organ transplant recipient. The vaccines aren't as effective on me, and the treatments aren't appropriate either. And I'd like to not be in lockdown.

Fresh air is good for all - let's get to it.

11/11
#covidco2