New study on HEPA air cleaners in Finnish school study. Kids fill in daily diary of respiratory symptoms and the prevalence of symptoms reduced when the air cleaner was on. However the prevalence also decreased when the air cleaner was on but HEPA removed 🧵

During the COVID-19 pandemic in 2021, researchers monitored air quality in marquees and semi-outdoor venues at UK mass gatherings to understand ventilation and airborne infection risk — work that directly informed how such events could safely reopen. 🧵

A lot of the analysis on this misses the mark: • “They weren’t on” — maybe, but filtration data says otherwise • “Too small / not ASHRAE 241” — data disagrees. And none of it actually says anything about transmission of respiratory illnesses. 🧵1/n

A lot of the analysis on this misses the mark: • “They weren’t on” — maybe, but filtration data says otherwise • “Too small / not ASHRAE 241” — data disagrees. And none of it actually says anything about transmission of respiratory illnesses. 🧵1/n

With UK heatwaves intensifying, are passive cooling strategies enough? At CIBSE’s seminar, experts explored natural ventilation limits, AirCon efficiency, façade carbon trade-offs & why overheating in schools is a learning crisis. cibsejournal.com/technical/pu...

With UK heatwaves intensifying, are passive cooling strategies enough? At CIBSE’s seminar, experts explored natural ventilation limits, AirCon efficiency, façade carbon trade-offs & why overheating in schools is a learning crisis. cibsejournal.com/technical/pu...

ASHRAE Standard 241 sets guidelines for how much “clean air” (via ventilation, filtration, etc.) is needed in buildings to reduce the airborne spread of infectious diseases like COVID-19. But how were these numbers chosen? 1/n

New oped from @benjonesieq.bsky.social & me 💨 The push for better school ventilation is well-meaning, but claims that it boosts cognition or learning lack strong, causal evidence. Many studies are low quality, poorly controlled, and often overstate effects. #IAQ #ventilation #education 1/5

The June issue of the #REHVA #Journal is out now! 📯 "#Education #Buildings: a Net Zero Transition Conducive to #Health and #Cognitive Performance". 📱 Read it online: www.rehva.eu/rehva-journa... 📨 Want to receive the #REHVA Journal in your inbox? Subscribe here: www.rehva.eu/newsletter-s...

New oped from @benjonesieq.bsky.social & me 💨 The push for better school ventilation is well-meaning, but claims that it boosts cognition or learning lack strong, causal evidence. Many studies are low quality, poorly controlled, and often overstate effects. #IAQ #ventilation #education 1/5

Just read one of the most ridiculous claims in a scientific journal discussion I've ever seen 👀 a therapeutic approach to gut microbiome to improve lung health impacts from air pollution 🤯 in rural Uganda! read on if you want to see how..1/n

New paper describes an in vitro method to infect cell culture with different flu strains by direct inoculation and by aerolised viral solution. Whilst it is an interesting novel methodology, I think it is limited in what it can tell us about the nature of aerosol transmission 1/n

The pandemic was a time when you would have thought people might want to improve their ventilation. But, behaviour change is hard because there are many barriers to change.

Great new study by on behavioural aspects of ventilation in hospitality venues. Many monitored venues had poor ventilation, but hosts list many barriers to improve - tho some venues attempt to improve following info campaign. let's see why it's not always simple to ⬆️ ventilation:

Great new study by on behavioural aspects of ventilation in hospitality venues. Many monitored venues had poor ventilation, but hosts list many barriers to improve - tho some venues attempt to improve following info campaign. let's see why it's not always simple to ⬆️ ventilation:

or a new study shows that either, or a combination of: ▪️reduced viral emission (bcos air cleaner added several days later from initial readings) ▪️changes to window ventilation ▪️presence of an air cleaner see below for fag packet calc to show it can't all be due to air cleaner...

or a new study shows that either, or a combination of: ▪️reduced viral emission (bcos air cleaner added several days later from initial readings) ▪️changes to window ventilation ▪️presence of an air cleaner see below for fag packet calc to show it can't all be due to air cleaner...

Off to see Bjork's cornucopia experience today. Trips to see her at the cinema are always an experience. Be that the harrowing Dancer in the Dark or the strangely hypnotic Matthew Barney art film Drawing Restraint 9. I'm sure there will be something to remember

This really interesting paper on SARS-CoV-2 viral emission dynamics in a hamster model has just been published. There’s lots to unpack, but thought I’d start on this expt that investigates characteristics of close range emission 1/n

Had a great time watching Stranger Things: The First Shadow. Fantastic special effects and illusions brought a gripping story to life.

Nice headline, scant on details. it's just a report based on a presentation given by a researcher. Look forward to seeing the methods and data. Researchers report that unknown if reduced exposure to pollution or pathogens or both is causative factor in reported absence reduction

Anyone know why the DHHS in the US have pulled the funding for this clinical trials for far UV to reduce indoor transmission of respiratory infections? nationalacademies.org/our-work/cli...

Disappointing that this headline suggests there may be causal links, when the article itself highlights the data is low quality wrt drawing any conclusions about UPF consumption and mortality bbc.co.uk/news/article...

Really interesting data showing how actual energy use is much lower than predicted energy use from residential EPC modelling. The gap may not be all down to how the housing is used by occupants but other assumptions that the model makes #cibsetechnicalsymposium

Looking forward to the CIBSE and IBPSA technical symposium today. I'll be at Session 7 Embodied Carbon and Energy Trade-offs: Optimising Building Systems

Gather 'round Bluesky, while I tell the hoary tale of epidemic vs. endemic. How can it be that pandemic interventions that were vitally important in 2020 are marginally effective in 2025? Science will give us the answers! Follow me... 1/

Enjoyed the citrus grove at Ventnor botanical gardens yesterday and we came across what we thought was some kind of diseased lemon. Turns out its a Buddha's Hand

yes, you definitely need to imagine...

Except the data doesn't support the conclusion. The air purifier is sized at 0.44 eACH based on 34m3 card and there is no measurement of ventilation/window usage despite this being the primary removal mechanism in the space. Viral emission rates also unlikely to be constant several days in a row

I've been doing this wrong, instead of highlighting flaws and uncertainties in the study I should have said, increased ventilation and reduced CO2 improves your cognitive ability.

Watching Harry Potter with the kids and I'm like my dad used to be when I was a kid watching Dad's Army. "He's dead now, and she is, oh he's dead too"

New study shows that there *might* be some limited affect of room CO2 on doing some online cognitive test game on a phone for students after they have finished class, but sample size is small. 🧵 1/n

Some cool natural ventilation aspects at the natural history museum. Check out this spider underfloor air vent and the cross ventilation made the vault lovely and fresh.

Interesting study that purports to show transmission of SARS-CoV-2 from humans to hamsters via the air. Transmission confirmed by immune responses from hamsters. However they are unable to isolate any viral genomic material from hamsters by rt-pcr so some uncertainty 🧵

Went to see the stage performance of My Neighbour Totoro yesterday. Wondered how they could possibly stage iconic scenes like this, but they did! Incredible set design and a wonderful family outing. Well worth seeing if you like Studio Ghibli

Spectacular gig last night from public service broadcasting @psbhq.bsky.social. Amazing visuals brought the music to life. Incredible performance, loops, pedals, horn section, vocoders creating a cacophonous background to the spoken word recorded footage

A fascinating correspondence from Dr Mildred Wells (pioneer of airborne transmission with her husband). She outlines that UV irradiating classrooms will be fore-doomed to failure in preventing the transmission of airborne infections bcos of other places of transmission 1947 1/n

A fascinating correspondence from Dr Mildred Wells (pioneer of airborne transmission with her husband). She outlines that UV irradiating classrooms will be fore-doomed to failure in preventing the transmission of airborne infections bcos of other places of transmission 1947 1/n

many comments I've seen on this article are outraged with sugary drinks and suggest banning slushies. Yet it seems the tax on sugar content that has resulted in glycerol being used as a sugar substitute ingredient which has resulted in children being hospitilised www.bbc.com/news/article...

Inside the PR campaign for private schools!

Saw a frog whilst out on a bike ride with the kids yesterday. We got excited when we saw a couple more. A few metres further on and we could no longer keep count of how many we saw!

New conference poster: No evidence for portable HEPA filtration units reducing respiratory infection episodes in care home residents • No evidence that episodes of fever/ delirium, gastrointestinal infections, falls or antibiotics consumed are reduced either

New conference poster: No evidence for portable HEPA filtration units reducing respiratory infection episodes in care home residents • No evidence that episodes of fever/ delirium, gastrointestinal infections, falls or antibiotics consumed are reduced either

#TBT seeing as there was some news suggesting everyone over 50 should take statin, here's a plot from my thesis that shows statins increased the activity of the enzyme that makes cholesterol. Odd, because statins inhibit this enzyme, see next for why 1/n

School run on world book day is fun seeing all the characters. Oompah Loompahs, thing 1 and thing 2, wizards and witches, tiger who came to tea, Dog Man, gangsta granny, where's Wally were just a few that I spotted

New ASHRAE position statement on CO2 ⏺️A reminder that evidence for direct impacts of CO2 on health and learning outcomes is inconsistent. ⏺️CO2 not an indicator of airborne infection risk due to other factors that do not necessarily scale with CO2 link in next post

In the 1800's Max Josef von Pettenkofer proposed 1000 ppm of CO2 as a marker of inadequate ventilation indoors (outdoor CO2 concentration was below 300 ppm at the time). Learn about this and MUCH more in ASHRAE's recently updated CO2 position document: www.ashrae.org/file%20libra...

Following positive press releases on an unfinished study into air cleaners reducing sickness in nurseries, other centres invested in filters but found no effect. Due to other practical problems eg noise, the trial was ended early. Article in next post 1/2

Whilst improved air quality in cities is welcome, despite this Guardian article saying the Clean Air Zones has saved the NHS money, it's worth reflecting that the study authors are less certain about their findings. *May* could be doing some heavy lifting www.theguardian.com/environment/... 1/3

Whilst improved air quality in cities is welcome, despite this Guardian article saying the Clean Air Zones has saved the NHS money, it's worth reflecting that the study authors are less certain about their findings. *May* could be doing some heavy lifting www.theguardian.com/environment/... 1/3