Thread by @moss_sphagnum

I had a chance to go to this @VSOrchestra Orpheum Theatre built after the Spanish Flu to be *pandemic proof* and WOW. This ventilating system is FULLY OPERATIONAL. Huge crowd 1/n

@VSOrchestra And under the seats there were these mushroom shaped objects...Fresh air from pipes provided a very gentle stream of air & note these air intakes were protected by the mushroom design. the stem emitted air, the umbrella part protected it 2/n

@VSOrchestra The air rose above the seats to the porous false ceiling above to vent all that air out! This was built in 1927 & it has better ventilation than most modern buildings #PandemicProof architecture 3/n

@VSOrchestra This ventilation system is fully operational. I estimated 1700 in that theatre! We need this 100 year old #PandemicProof design that was demanded by the public so wary of death from #SpanishFlu . They were ready for #covid19bc! Are we?

If there was a way out of our #covid19bc pandemic, here it is, a design from 100 years ago from the people who knew #SpanishFlu was airborne. Here is the article below that made me curious to go to the Orpheum with my aranet4

And a word of caution...so far the CO2 readings are showing great ventilation for 1700 people at <600 ppm and 1200ppm for 3000 people. I would love to gather more data on this! Have a look at Daryl's experience:

So my party took readings at the front, back and balcony. Daryl's balcony seats had 1200ppm around double the reading from yesterday

1200ppm is actually the CO2 levels at my home where I live with 3 other humans & a kitty. This level for 3000 people is still extraordinary but that means full capacity concerts might need a #maskmandate

...CO2 in my house right now with 3 humans inside & a kitty

Those #SpanishFluisAirborne floor vents at the #orpheum were designed into many public spaces the 1920s : theatres, lecture halls. urbanremainschicago.com/news-and-event…

"The result of supplying the fresh air at low level and letting buoyancy drive the air through the space creates an improvement in air quality"

google.com/amp/s/blog.pri…

...and look what I found! A test of how a #PandemicProof ventilating system designed for #SpanishFlu actually works to use #displacement ventilation to supply fresh air in an old theatre in London! #COVIDisAirborne #covid19bc #orpheum #science

...That Royal Albert is not exactly the same as our #orpheum but it's cool to see this #displacement ventilation at work. It is currently used in modern theatres seeking LEED certification so #EnergyEfficient too #COVIDisAirborne #PandemicProof #covid19bc

" we show that displacement ventilation, ...where air is drawn in through lower-level inlets & extracted at high level, can significantly reduce the spread of airborne contagion, and save the lives of healthcare workers, carers & patient " 1/3 #covid19bc royalsocietypublishing.org/doi/10.1098/rs…

"In mixing ventilation, the occupant is surrounded by mixed air of uniform properties, such as the concentration of a contaminant—a bit like lying in dirty bath water. By contrast..." 2/3

"  in displacement ventilation the occupant is surrounded by newly arrived air, and pollutants generated near or by the person are lifted towards the ceiling by the rising warm air—rather like being in an inverted shower and rinsed with clean water. " 3/4

...from the same paper, an illustration of how displacement ventilation can be used in healthcare 4/4

Looks like the New Orleans #Orpheum , built around the same time uses displacement ventilation too! m.facebook.com/orpheumnola/po…