iiinova — where your digital self keeps evolving

Aaron Collins @masknerd.bsky.social · 04/09/2026

Highlights that pollution has short terms consequences too. N02 is a proxy for vehicle emissions (NO from engines reacts with ozone to form NO2) and is closely related to ultrafine particles too. UFP and PM2.5 are typically not very correlated,so limited NO2 corr. too. More reason for electric cars

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Aaron Collins @masknerd.bsky.social · 16/07/2026

[1/2]Nearly 200 ug/m^3 of PM2.5, can anyone guess what the ultrafine particle count(UFP) looks like? About 11,000 p/cm^3 which is normal for this area. WHO suggested guidelines are less than 10,000 so it's not bad. Why might you ask?

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Aaron Collins @masknerd.bsky.social · 18/06/2026

[1/3] As promised, the results from the long-duration testing of a MPR 2800 filter taped to a Taotronics AP-003. 1.5 years later and we see drop of *~70%* in performance in the 0.3-0.5 um size range from the test when new!!! (Same testing setup but at different times so apx ±10% error)

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Aaron Collins @masknerd.bsky.social · 17/06/2026

About 1.5 years ago I taped on a 16x20 3M MPR2800 filter to a Taotronics AP-003. It boosted the CADR by about 20-30%. Let's take some guesses as to what it is a 1.5 years later? You think it's still performing at 90% of where it was, 50%, or 30%? Let's see your guesses! Will post the CADR tomorrow

A white air cleaner with a now darkened air furnace filter taped to the front. It fit closely to the size of the air cleaner. Gray tape is visible. It's placed in a dining room with wood floors, and a carpet visible in the edge of frame.

A close up of very dirty filter, with dust bunnies visible between the tight pleats of the filter. It's dark grey with contrast to the white frame of the filter.

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Aaron Collins @masknerd.bsky.social · 05/05/2026

@openaeros.bsky.social trade show booth and bonus poster. It's a great poster, as it highlights that air cleaners are very effective against ultrafine particles (which are tiny) and PM2.5. We don't need anything fancy to start bringing clean air to all. All we need are fan+filter.

Picture of Aaron in a selfie showing the OpenAeros booth with a table. On top of it are two OpenCPC's along with various schwag and demo.

Aaron with an uncomfortably large smile in front of a poster that shows graphs but it's too dark and too small to see

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Aaron Collins @masknerd.bsky.social · 04/05/2026

Another flight another...wait no V-flex? I always like the easy wins in terms of reducing risk, but the thermal comfort of this mask has been my go to lately. I haven't posted a lot, but I have rocked this combo for an entire year and my no-COVID streak continues. Off to talk clean air at ASIC LA!

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Aaron Collins @masknerd.bsky.social · 25/04/2026

A simple and well written piece. Perfect is the enemy of good. We have the tools today to clean the air and we should use them. We have PAC's, HVAC, IAQ sensors and even masks. If and when we start running into issues that the air is too clean indoors, well that is a good problem in my book.😁

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Aaron Collins @masknerd.bsky.social · 21/01/2026

We need to do air filtration for PM2.5 and other contaminates, but when stacked with GUV I think we have a path the end of many airborne diseases. Great work by @donmilton.bsky.social in helping other learn more about it.

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Aaron Collins @masknerd.bsky.social · 04/12/2025

We made it easy to use the OpenCPC, and how better to show it than via a video. Funny how in the last 5 years I have made more videos than the previous 35 years of my life combined. 😄

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Aaron Collins @masknerd.bsky.social · 11/11/2025

It's not always easy to explain how we simplified CPC's, but I think this image really makes the case on how we re-invisioned what the optical counter within the CPC could be.

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OpenAeros @openaeros.bsky.social · 03/11/2025

Hope everyone enjoyed their Halloween weekend! Here at the OpenAeros offices, everyday is spooky season. 👹🎃💆‍♂️

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Aaron Collins @masknerd.bsky.social · 02/11/2025

@mfrumholtz.bsky.social just listened to you on the Wedge Live podcast. There were a few misstatements about air pollution that I think are relevant to the discussion. If you would like to chat about them and connect just let me know.

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The Safer Air Project @saferairproject.bsky.social · 29/10/2025

Thank you for sharing (and registering too)! If the timezone makes it difficult to attend live, do register so we can let you know as soon as the recording is up.

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Aaron Collins @masknerd.bsky.social · 29/10/2025

The @saferairproject.bsky.social is hosting an amazing event on why IAQ matters, IAQ performance standards and policy discussions. If you are in AUS a must attend. Livestream option (hybrid) and recording afterwords. Just registered myself, should be great! Register here -->https://bit.ly/ssa-2025

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OpenAeros @openaeros.bsky.social · 20/10/2025

Miss our first OpenRespirator Creative Cohort Live meeting? No worries, we've posted our discussion here! Get to know our cohorts, get read-in on their efforts and progress, and see some early designs. youtu.be/C0Q0ZH6e5AA

youtu.be

OpenRespirator Creative Cohort: Live Meeting 1

YouTube video by OpenAeros

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OpenAeros @openaeros.bsky.social · 06/10/2025

This year, we’ve been working with a team of passionate, creative makers to put our open source respirator prototype manufacturing methods to the test. We’re so excited to be introducing you to a couple of them this week. In the meantime, here’s some background on what we’ve been up to: (1/4)

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Linsey Marr @linseymarr.bsky.social · 24/09/2025

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.

People in conference room at the UN building

The global pledge for healthy indoor air: That clean indoor air is a fundamental human right for protecting health and safeguarding well-being

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OpenAeros @openaeros.bsky.social · 23/09/2025

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

OpenAeros founder Aaron Collins poses for a selfie from the floor on the UNGA High Level Side Event On Indoor Air Quality with the OpenCPC. The CPC is on, Collins is wearing a mask and suit, and the meeting room behind him is filling with people from across the globe who are convening to discuss IAQ policy.

the OpenCPC sits facing a filling room at the UN General Assembly Side Event on Indoor Air Quality. Its screen displays a live particulate count and the screens labelling participant and audience seats face back, reading #IndoorAir

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Aaron Collins @masknerd.bsky.social · 23/09/2025

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.

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Aaron Collins @masknerd.bsky.social · 22/09/2025

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...

webtv.un.org

Healthy Indoor Air: A Global Call to Action

Join global leaders, policymakers, scientists and health experts for Healthy Indoor Air: A Global Call to Action – the inaugural High-Level Side Event on indoor air quality, to take place on the sidel...

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Aaron Collins @masknerd.bsky.social · 22/09/2025

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.

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Aaron Collins @masknerd.bsky.social · 15/09/2025

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...

linkedin.com

The OSLUV Project hiring Grant Project Manager in St Paul, MN | LinkedIn

Posted 9:01:10 PM. Organization: The OSLUV Project, Saint Paul, Minnesota.Status: Immediate OpeningDuration: Summer…See this and similar jobs on LinkedIn.

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Aaron Collins @masknerd.bsky.social · 15/09/2025

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

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Aaron Collins @masknerd.bsky.social · 18/08/2025

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...

nytimes.com

Wildfire Fighters, Unmasked in Toxic Smoke, Are Getting Sick and Dying

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Aaron Collins @masknerd.bsky.social · 07/08/2025

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/...

jacc.org

Effect of HEPA Filtration Air Purifiers on Blood Pressure: A Pragmatic Randomized Crossover Trial

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Aaron Collins @masknerd.bsky.social · 31/07/2025

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!

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Aaron Collins @masknerd.bsky.social · 08/07/2025

[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...

nytimes.com

Do I Really Need an Air Purifier?

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Aaron Collins @masknerd.bsky.social · 04/06/2025

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

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.

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Aaron Collins @masknerd.bsky.social · 23/05/2025

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

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Aaron Collins @masknerd.bsky.social · 19/04/2025

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

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

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Don Milton @donmilton.bsky.social · 17/04/2025

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.

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Aaron Collins @masknerd.bsky.social · 13/04/2025

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...

nature.com

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...

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Aaron Collins @masknerd.bsky.social · 12/04/2025

[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...

academic.oup.com

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

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Aaron Collins @masknerd.bsky.social · 10/04/2025

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

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Public Health Action Network @publichealthaction.bsky.social · 26/03/2025

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!

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Aaron Collins @masknerd.bsky.social · 20/03/2025

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

behealthyusa.net

Free Mask

Receive our latest updates about our products and promotions.

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Aaron Collins @masknerd.bsky.social · 14/03/2025

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.

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Don Milton @donmilton.bsky.social · 28/02/2025

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

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Aaron Collins @masknerd.bsky.social · 12/02/2025

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.

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Aaron Collins @masknerd.bsky.social · 07/02/2025

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

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Aaron Collins @masknerd.bsky.social · 23/01/2025

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.

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MaskTogetherAmerica @togetherwemask.bsky.social · 18/01/2025

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.

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Aaron Collins @masknerd.bsky.social · 05/12/2024

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.

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Aaron Collins @masknerd.bsky.social · 01/12/2024

[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.

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Aaron Collins @masknerd.bsky.social · 01/12/2024

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.

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Aaron Collins @masknerd.bsky.social · 13/11/2024

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-...

officecrave.com

Lorell HEPA 420 Air Purifier (00204) | OfficeCrave.com

Shop Lorell HEPA 420 Air Purifier (00204) at OfficeCrave.com and get expedited shipping.

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Aaron Collins @masknerd.bsky.social · 21/10/2024

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

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Aaron Collins @masknerd.bsky.social · 01/09/2024

@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.

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Aaron Collins @masknerd.bsky.social · 29/08/2024

@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...

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