The momentum for clean indoor air continues to build. I attended the inaugural High-Level Side Event on indoor air quality at the UN General Assembly yesterday. Short remarks by Lidia Morawska @joeallenjoe.bsky.social @isiaq.bsky.social Pres. Kerry Kinney, ASHRAE, WHO, UNEP, many others.

Aaron (and our little CPC! 🥹) are taking their places on the floor of the UN! This year is the inaugural General Assembly High Level Side Event on Indoor Air Quality and we're so excited to participate. The panel will open soon, watch along here: webtv.un.org/en/asset/k1v... #IndoorAir

Glad to bring the "little CPC that could" to the Healthy Indoor Air event at the UN today. The conversation in clean air are moving in the right directions. Open source hardware will be part of the solutions and proud to show off the OpenCPC as part of tools that can help us measure it.

An early AM flight to NYC to join the Healthy Indoor Air event at the UN tomorrow. This is an important step in the process of helping get clean air legislation. You can watch it live tomorrow between 3:30 - 5:30PM ET. webtv.un.org/en/asset/k1v...

Clean air is not complicated, and costs less than $10 per kid per year to do. This is the 4th year of managing this for my son's school. What happens when he moves to the next school, who will keep doing this for the other kids? We need clean air standards and legislation.

Passionate about clean air, environmental justice, and community-based participatory research? The OSLUV Project(501c3 non-profit) is hiring for a Grant Project Manager position for a state funded air quality research effort. You also get to work with me 😂 www.linkedin.com/jobs/view/43...

I couldn't think of a better way to have spent the last 2.5 years of my life. I am incredibly proud of what the team at @openaeros.bsky.social was able to accomplish. There were many who said this was impossible, but we did the impossible and this is just the start. 😁 #cleanairisahumanright

It's crazy to me to see the US Forest Service deny the ever obvious health risks with breathing wildfire smoke. We lack good PPE because there is a limited market, it's a limited market because the Forest Service denies there is a problem. Need a demand pull for PPE. www.nytimes.com/2025/08/17/u...

I made a bold claim this spring, if you recontextualize the 2022 CDC mortality data and look at the root cause of mortality, **the #1 killer in the US stuff you breathe**. Clean air leads to better health, including lower blood pressure. www.jacc.org/doi/10.1016/...

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!

[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...

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

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

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

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.

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...

[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...

I have been so quiet because every day there is some massive impact to OpenAeros. Whether it's crazy tariffs and massive disruptions to supply lines, or the entire gutting of NIOSH. Huge impacts what we have been working on, some weeks are tough. The Little OpenCPC That Could won't be stopped though

We're coming to Pandemic Pals! This Saturday, call into the @pandemiccollab.bsky.social Pandemic Pals online meeting (5pm PDT/8pm EDT) and join our PHAN breakout room! We'll talk about our work including our upcoming fantabulous global COVID resources directory called SAFER. Zoom link coming Friday!

BeHealthyUSA is offering free kids masks, just pay shipping. Wondering if any MaskBlocs can take advantage of it? behealthyusa.net/collections/...

Haven't posted much on any social media as I have been the busiest I have ever been in my life. It's all good though, because it means progress. Got a few minutes to chill on the BART and read a great book. At UC Berkeley for a talk on Clean Air and will share the video link when it's available.

NIH just canceled the Respiratory Virus Transmission Meeting scheduled for early April - Great timing as H5N1 may be only one mutation away from rapid spread between humans. @carlzimmer.com @carlbergstrom.com @publichealthumd.bsky.social @linseymarr.bsky.social #public-health #h5n1

Completely silly this happened you can't cancel science. We will continue to collect some cool data and share it anyways. Plus I feel like you only get a handful times to reference an Indigo Girls song in your title.

If you are interested in moving the needle on respirator design, now is your chance.

I forgot to quote tweet this a few weeks ago, I blink and weeks disappear. Go check it out if you want to learn a bit about what open source means in context to the OpenCPC.

Tomorrow is our urgent discussion on PPE featuring Dr. Omer Awan, MD MPH CIP, Aaron Collins, @masknerd.bsky.social and Mask Bloc LA @maskblocla.bsky.social organizer Babs @itsbabs.bsky.social Date: January 19th Time: 7 PM - 10 PM EST Register: bit.ly/Jan19MaskForum Watch recording if you miss it.

Great paper on the theory of why not-HEPA is actually better. It makes two assumptions that I think need to be updated. My guess is with electret media, 90% is probably target 1. Doesn't consider electrostatic filter media 2. That blower efficiency curves are fixed, but still good first order est.

[1/2] All that matters is CADR! Ignore things super-hyper-mega HEPA. Often times a filter that only provides 70-80% actually provides more clean air than a filter that is 99.97%(HEPA). I used a 16x20 3M filter taped to a Taotronic AP-003(with no internal HEPA installed) and got a 30% boost in CADR.

I am pulling over all Tweets from X, so you might see a bunch of old stuff from me. Hold tight should all be done over the next few days.

Air Cleaner Hot Tip. The best bang for the buck air cleaner is the Lorell 420, which if you look around can be had for ~$42. It's discontinued, so make sure you buy a few extra filters at the same time. However at this price it's cheaper per CFM than a CR Box www.officecrave.com/lorell-hepa-...

Another flight...another V-flex reducing my inhaled dose. Off to an aerosol science conference in Albuquerque where we are launching the OpenCPC! #AAAR2024

@OpenAeros needs some help! If you have any connections with anyone familiar with IEC 61010 and CE compliance we would love to chat. We get the basics, but want some help navigating the labs & companies. Basically just need the inside scoop since this our first time.

@mnstatefair I hope this is something you can address with your security teams. COVID cases are sky high here in MN right now, and people should be able to take precautions to protect themselves and not be harassed. Your FAQ clearly says its...

For those wondering, this is how I started the conversation on air cleaners for my son's school district. I went to speak to the school board. Funny that 3 years later we are still talking about the same things....

What does an extra ~2-2.5 eACH cost for a classroom? This year it was $30 for air filters and $3 in⚡️, for a whopping $1.43 per kid per year!!! Took 7 hours to do 23 rooms. This ain't rocket science. Not a paid endorsement, no connection to brand but 0/23 failures in 3 years🤷‍♀️

Excited to update everyone on OpenRespirator. First step was to build the tools to make a mask. We developed a tool set which allows prototyping in silicone and co-molded plastic for $30 with one time capital cost of $4K, and of course all open-source! https://youtu.be/2BCotdFDuuc

This can only mean one thing 😁 The world's most characterized bathroom/lab is firing back up for some testing

The fact I am on this plane is amazing given right now. Was great to pitch clean air to so many interested parties, the tide is turning on clean air. As always, my trusty V-Flex helps reduced my inhaled dose. 23 days of travel, 5 flights, countless trains and still a NOVID.

Thank you Violet for advocating for clean air. It's not always easy to stand up and speak out when so many others want to ignore a problem. @BenAffleck sometimes the smallest acts can lead to biggest changes, I hope you can support her...

A reminder that COVID-19 is bad for everyone, and glad to see better masks being used. @vismaleaseabike a reminder that my offer still stands, well can keep Jonas and @WoutvanAert from getting it. Heck I am already in Europe...

Y'all masking? Day 13 of an international trip, 2 flights, 3 long train rides and I can't count how many subway/metro/tube rides. Here our simple rules. 1. Well fitting masks when indoors 2. Patio/Outdoor dining only(or takeaway) 3. Open window in hotel/apt. when there.

Another flight another V-Flex. 5 flights and 3 trains over the next weeks as we do a whirlwind visit of Europe, followed on by a week long work trip. Will jam out to @joost_kleinn Europapa for the full 7 hour flight in prep.

Bummer to not see @seppkuss race the tour, I hope you heal up. Repeat COVID infections are bad for everyone. Yearly reminder to @vismaleaseabike that the crew at @OpenAeros have the tools and knowledge to help stop illness(can't do much with the bikes...

[1/9]Seeing discussion about this study looking at total outward leakage of masks worn by infectious people. Some good takeaways but summaries are missing the bigger point –it’s all about fit and filtration and not that it was an N95(but it...

The good news is that @trishgreenhalgh and many others wrote a great piece that highlights masks work. The bad news is that the laws of physics still work everywhere else too, especially those involving bicycles and immovable objects.

I see this Rolling Stone article rehashed, with wrong and very out of date info. It's out of date because RS just keeps recycling the article from Aug 2020, every link is an affiliate link so RS gets paid when you buy. How about an update...

Easy to source Champak masks are back! Thanks @projectn95 for the helpful email to let me know, I miss you all 😀 https://www.planethalohealth.com/collections/n95-niosh-respirator-adult/products/champak-flat-fold-pc520m-pc520l-adjustable-n95-masks-m-l-pack-of-15

@openaeros.bsky.social has done what many thought was impossible:  create a low-cost, open source condensation particle counter. It’s the core technology needed for high-performance mask fit testing, and we are excited to show off our progress.  Big thanks to Balvi for believing in us.

A new pre-print from @Jianyu16, @drkristenkc and @Don_Milton. Take-away is something you will hear a lot from me, *it's all about fit*! One mask of each type tested, N95 was best(was a duckbill). They fit a wider range of faces than bifolds. Surgical =...