A9(1). The most important change is that we have to pay attention to the FIT of the mask. No gaps between mask and face.
- Fit doesn't matter for ballistic droplets, only need a parapet
- Fit critical for aerosols (like smoke), since can go through gaps
1/ New paper in @ScienceMagazine: "Mandating Indoor Air Quality for Public Buildings"
Explaining current status of indoor air quality standards (in short: bad or non-existent), the huge health benefits that would arise from them & proposing a path forward science.org/doi/10.1126/sc…
2/ "People living in urban & industrialized societies, which are expanding globally, spend more than 90% of time indoors, breathing indoor air (IA)."
"Most countries do NOT have legislated indoor air quality (IAQ) performance standards for public spaces"
1/ Measuring CO2 indoors in a 10 day trip from US to Europe & back
Bus @RideRTD to Denver airport, poorly ventilated as usual.
We have not left town yet! In previous trips it kept increasing, we'll see this time.
2/ For background on what CO2 indoors indicates and more details, see
TLDR:
- We exhale 40000 ppm CO2
- Outdoors: 420
- Each 400 extra ppm indoors = 1% extra rebreathed air
- CO2 makes us dumber, indicator of virus & pollutants. Does not capture filteringdocs.google.com/document/d/e/2…
3/ Or by reducing recirculation. Some recirculation is ok if well-filtered, saves energy.
Energy-recovery ventilators allow ventilating well with limited energy use.