Aaron Collins

Air cleaners are always helpful. How helpful they are depend on the size of the space, the model you have and the speed you run it at.

It's the SaveWo 3D Ultra, which is KN95/KF94/FFP2 depending on where you buy it.

Poor air quality? Throw on a hyper-breathable mask and do your activities. Still managed over 18 mph highlighting that we have the technology and we should use it!

It's very off base, not sure if it was the reporter misunderstanding but appears to be a direct quote. It's bonkers.

Slow response 😁 but I think myself and others interpreted your first post to mean we have to measure all constituents to define good air quality, but you had meant you can't just use one single metric, such as CO2 to define "air quality". Makes more sense now!

Graph showing Hazard Ratio associated with PM2.5 exposure, strong linear correlation that lower PM2.5 shows lower mortality.

[8/8]
Not sure who is advising the American Lung Association( @lungusa.bsky.social ), but this is so wrong. There are plenty of evidence that reducing your PM2.5 exposure reduces mortality. Vacuuming you carpet doesn't solve this problem. THERE IS NO SAFE LEVEL OF PM2.5! Lower is always better

[7/8]
They want you to wash for frigging bedding to stop PM2.5 exposure...what!?!?!

"As a first step, she advises people concerned about indoor air quality to use a vacuum cleaner with a HEPA filter, to wash bedding often to get rid of dust mites and to make sure there’s no mold in their homes."

[6/8] Air cleaners are literally your fist line of defense(including HVAC+vent). @linseymarr.bsky.social noted correctly that cooking makes the most particles. How do you get rid of them? With a friggin' air cleaner or vent!
But what quote really takes the cake from the @lungusa.bsky.social?

[5/8]
Saying not to use something because you think it is expensive, is shortsighted and shares so much similarity to the mask debates of 2020-2021 it hurts my head.
We have lower cost solutions like the CR Box, and not advocating for the solutions will never make them cheaper! Identify the problem!

[4/8]
3. This quote from the @lungusa.bsky.social though is so fundamentally wrong that I could write three whole posts on it..
"According to Ms. Pruitt, air purifiers “should not be the first line of defense for clean indoor air” for most people, especially since their cost can be prohibitive."

[3/8]
2. Carbon filters remove VOC's, and early data also shows it removes ozone. However, you need a lot of it and it must be refreshed often. Most air cleaners have very little, really just a dash for marketing B.S. when you literally needs pounds of the stuff.

[2/8]
1. All that matters is CADR. It has been shown by the CR boxes, with ~75% single pass efficiency still outperform almost all HEPA units. Their CADR is better because they just flow so much air. HEPA doesn't hurt, but buying a 300 CFM CADR device is always better than 100 CFM HEPA device.

Do I Really Need an Air Purifier?

[1/8] It has been awhile since I have read something that has so many mistakes...but the quote from the American Lung Association really takes the cake! @nytimes.com you really need to do better. Let's dig into what they got wrong.

www.nytimes.com/2025/06/30/c...

Quality , noun - a degree of excellence

It's a start to give some degrees of excellence for what can commonly be measured. IAQ is complex, but we have to start somewhere. Eventually you have to create metrics, lest what else do we judge it based on?

The OpenCPC, a square white and black box displays a particle concentration of 71221 particles/cm^3. The background is a parking lot with shirts and greenery, with a large warehouse in the background. It's overcast and rainy in the picture.

Yikes! Canadian wildfire smoke in the Twin Cities brings some serious increase in ultrafine counts even on a rainy day.

It's almost exclusively the result of emissions from vehicles. There were busses behind me idling, hence the really high levels.

Thanks Boston for the wonderful Nor'Easter weather and some high ultrafine counts. Food and people were good though. 😁

I will still come back.

[2/2] That is because there were 22 air filters in the space, and it met ASHRAE 241 levels of clean air. We have the tools and this venue showed that it's possible to significantly reduce you inhaled dose.

[1/2] We are all peeing in the same pool, we just can't see it! We also can't see poor air quality is the #1 cause of death in the US for 2022. I make this case in a recent talk I was invited to as part of ETHSF d/acc day. Other interesting talks in there too. Probably wondering why no mask?

That is 100% correct! Although it should have been called a drums and bass show, two live drummers for the drum breaks.

In Aaron's hand is a pair of glasses, ear plugs and black mask with a back drop of a city street.

My concert essentials for 2025. Now the question is can you identify the drum and bass legend I went to see?

Hahaha...with all the tariffs you now have to pick a domestic company !😂 In all seriousness you have done great work and been a great advocate for masks and science around them.

First Trump and MAGA fought mask mandates bec they infringed freedom of healthy people. Now Trump mandates that universities ban masks infringing freedom of people with health concerns.

Freedom? Doublespeak?

Glad to see that the rest of the world agreed on a pandemic control treaty today.

A natural experiment on the effect of herpes zoster vaccination on dementia - Nature Using a natural experiment that avoids common bias concerns, this study finds that the live-attenuated shingles vaccine reduced the probability of a new dementia diagnosis within a follow-up period of...

More evidence that viruses are bad. If you haven't been following @polybiorf.bsky.social you should. There are no good viruses. While infections for many may be "mild", the life long implications are huge. Want to live longer? Avoid viral infections. Many are airborne!
www.nature.com/articles/s41...

[4/4] It also highlights an important aspect....airborne infections can go from humans to animals(think about pets!). Importantly it likely can go the other way too. Future pandemic might come from animals by airborne transmission.

[3/4] This is big because you have a mechanism to test mitigations. Do masks help? Does clean air help? Does UV work? How well does this all work in the real world. There are some clear clues about where they are going given discussion of masks, and authors involved. Just Google "Ed Nardell" 😍

[2/2] It showed human to animal transmission, hamsters respond to being exposed to room from active COVID infections. Interestingly not a typical infection though. I think first study to show human to animal. Previous studies have been ferret to ferret, but now even more evidence. This is big...

Human source SARS-CoV-2 aerosol transmission to remote sentinel hamsters AbstractBackground. Bioaerosol-mediated transmission of COVID-19 via building ventilation systems has yet to be convincingly demonstrated. We used the Sout

[1/3] Not surprising to many, but a big deal in terms of further science on airborne transmission of COVID. It's basically a repeat of the famous Wells Riley experiments of the 1960's. Why this is a big deal?

academic.oup.com/ofid/advance...

Also interesting that a IQAir HEPA+Carbon was just as effective without the NO or Acetone issue.

It's totally insane and only results in people being hurt or killed. We are less prepared now for a pandemic than in 2020 and it's crazy to me.