There are some great bits in this webinar by @UNISONinSchools about air quality in schools.

There are some great bits in this webinar by @UNISONinSchools about air quality in schools.
Did you catch these bits on how clean air can help... https://t.co/Fi1T8P4Xbv pic.twitter.com/xl6Sm2cQMa

— tern (@1goodtern) May 28, 2025

Kids Are Headed Back to School. Are They Breathing Clean Air?

Clean indoor air protects against diseases such as COVID and flu, but we’re not doing enough to ensure it

Across the U.S., kids are headed back to their classrooms—just as COVID nears a fresh, late-summer peak. Somehow, four years into a viral pandemic that everyone now knows spreads through the air, most schools have done little to nothing to make sure their students will breathe safely.

We—and especially our children—should be able to walk into a store or a gym or a school and assume the air is clean to breathe. Like water from the faucet, regulations should ensure our air is safe.

“Air is tricky. You can choose to not partake of the water or the snacks on the table, but you can’t just abstain from breathing,” notes Gigi Gronvall, senior scholar at the Johns Hopkins Center for Health Security and an author of a 2021 report on the benefits of improving ventilation in schools.

The COVID-causing virus SARS-CoV-2 is far from the only airborne risk in schools. There are also other respiratory viruses, smoke from wildfires, mold spores, off-gassing from plastics and other compounds, air pollution from traffic and industry, and allergens that worsen asthma and add to sick days. Yet federal air standards are stuck in the 1970s, when they were mostly aimed at protecting people from secondhand tobacco smoke, says Joseph Allen, director of the Healthy Buildings Program at the Harvard T. H. Chan School of Public Health. Fully updated standards for buildings are years or even decades away.

It’s hard to assess just what schools have or haven’t done to improve indoor air quality. No one—not one federal agency—collects nationwide air quality data on individual schools. Schools could use federal money to update air filtration and ventilation during the height of the pandemic. But a 2022 Centers for Disease Control and Prevention survey of school districts found that only half had taken simple steps such as opening windows or doors or using fans, and even fewer had upgraded ventilation systems...

Kids Are Headed Back to School. Are They Breathing Clean Air? | Scientific American

Breaking: AC Broken at Springbrook HS, Median Temp of School 83 Degrees at 10:20 AM

Let's begin with the definition of "median" from Webster's Dictionary  "being in the middle." 

And then word from students at Springbrook High School that they are in the second day of no air conditioning due to a broken HVAC system.

What's new this year is that MCPS has installed indoor air monitors in EVERY SINGLE CLASSROOM in the entire school system.  Parents and guardians can now monitor the indoor air quality of their child's school in real time. 

However, MCPS administrators only want parents to have limited information about the indoor air of schools.  Therefore, MCPS is only making the median indoor air temperature of the entire building public.  

So for each MCPS school building, even though every single room has an indoor air monitor, MCPS only releases one number for the entire building.  The number released is the median temperature number for the entire school building.

Today, we know that as of 10:20 AM the median temperature of Springbrook High School is 83 degrees.  That's the median temperature.  How hot are half of the classrooms in that building right now?  

EPA testing shows homemade air filter effective at removing viruses from air

EPA Testing Shows the Power of D-I-Y Air Filters to Trap Viruses

The results are in: U.S. Environmental Protection Agency research testing of do-it-yourself ‘Corsi-Rosenthal Box’ indoor air filters shows they are 99% effective in removing airborne virus. The 'Owl Force One' device tested by the EPA was built by UConn Indoor Air Quality Initiative researchers with Middletown, Connecticut public school children.

There is a low-cost way for you to protect yourself and reduce your risk of respiratory diseases such as flu, RSV, and COVID-19. Build yourself a Corsi-Rosenthal box (CR box) in 30 minutes with just $60 worth of common hardware store supplies.

In July, U.S. Environmental Protection Agency scientists began several weeks of advanced bioaerosol chamber testing to assess the efficacy and power of this air filter against infectious aerosols, like the virus that causes COVID-19. The results are in, and they are good.

The U.S. EPA Office of Research and Development’s 3,000 cubic ft. bioaerosol chamber testing results show that the CR box removes 97% of infectious aerosols in just 30 minutes, and 99.4% within 60 minutes. Importantly, the device successfully captures a surrogate virus for SARS-CoV-2, the virus that causes COVID-19.

A team of EPA scientists led by Katherine Ratliff conducted the bioaerosol chamber testing of the CR box after testing more expensive air cleaning technologies throughout the pandemic.

“The study results are extremely exciting,” says EPA’s Ratliff. “These CR boxes really work. The Corsi-Rosenthal box works against infectious aerosols in the air. The results are really powerful. Three different sets of biochamber testing data show that these air filters reduce the amount of infectious virus in the air and capture both smaller and larger sized particles. CR boxes are more effective at reducing concentrations of infectious aerosols in indoor air than some of the more expensive technologies that we tested.”

“These scientific results are huge!” says Marina Creed, APRN, director of the UConn Indoor Air Quality Initiative. “These inexpensive, do-it-yourself air filters are for everyone. If you put this in your home, it will remove infectious germs that cause disease from the air. Schools, students, and teachers if you run one of these inside your classrooms it can reduce your exposure to viruses and bacteria, reducing the risk of disease transmission, meaning you are less likely to get sick.”..

EPA Testing Shows the Power of D-I-Y Air Filters to Trap Viruses - UConn Today

Inexpensive, do-it-yourself air cleaner that can be easily constructed out of a box fan and MERV-13 furnace filters.

 The Corsi-Rosenthal Cube (sometimes called a Comparetto Cube) is an inexpensive, do-it-yourself air cleaner that can be easily constructed out of a box fan and MERV-13 furnace filters. The Corsi-Rosenthal Cube can give whole-room air cleaning performance comparable to commercial HEPA air cleaners that are 10x or more the cost. Total cost is around $100USD ($130CAD)...

Corsi-Rosenthal Cube - Encycla

Why Haven’t We Made It Safer to Breathe in Classrooms?

Two years ago, we got a chance to assure parents and teachers, in any future epidemic, that the air in classrooms was safer, making it easier for children to attend school in person and avoid learning loss and isolation.

In March 2021, Congress allocated $122 billion for schools to cope with the Covid pandemic and its aftermath — to hire tutors, retain teachers or improve their facilities. Public health and clean air advocates hoped that this would lead to widespread improvements in classroom ventilation and air quality to help ward off future pathogenic threats and reduce problems like dust, allergens and wildfire smoke.

But only about 34 percent of school districts said they used any of the money to upgrade their heating ventilation and air-conditioning systems, according to a recent survey from the Centers for Disease Control and Prevention. About 28 percent more installed in-room air cleaners, 8 percent said they installed ultraviolet lights — a more expensive and complicated method — and the rest reported no changes that would substantially improve air quality.

Moreover, once the federal spending was approved, aggressive salespeople descended on school officials who were struggling to open. School officials often were persuaded to spend more for products that many scientists believe aren’t substantially more effective than cheaper alternatives that have been thoroughly studied. Some of the products could even be dangerous...

Opinion | Few Schools Have Covid Relief Funds to Improve Air Quality - The New York Times (nytimes.com)

***FYI*** Carbon Dioxide: The Invisible Indoor Air Pollutant in California's Classrooms

Poor ventilation and air quality in California's schools could be impacting students' health and academic performance

Carbon Dioxide: The Invisible Indoor Air Pollutant in California’s Classrooms – NBC Bay Area

Investing in indoor air quality improvements in schools will reduce COVID transmission and help students learn

As fall temperatures cool across the U.S., many schools will struggle to ventilate classrooms while also keeping students and teachers comfortable and healthy. Children and teachers spend over six hours a day in classrooms during the school year, often in buildings that are decades old and have inadequate heating, ventilation and air conditioning, or HVAC, systems.

Fall 2022 marks the start of the fourth school year affected by the COVID-19 pandemic, which has spotlighted the importance of indoor air quality in schools. Ideally, all school buildings would have adequate ventilation, filtered air in each classroom and windows that open. Sadly, this is not the case – and indoor air quality in many schools is poor as a result. This is especially problematic in the wake of the U.S. Centers for Disease Control and Prevention’s August 2022 COVID-19 guidance for schools, which scales back other measures for limiting transmission, such as masking, testing and quarantining.

Beyond minimizing COVID-19 transmission, indoor air quality also matters for student academic performance. This is especially important given the learning losses that many children experienced in the first two years of the pandemic. Hot, stuffy classrooms make it harder for students to learn. So do cold classrooms.

Our research focuses on indoor environments and health – an area that has received increased attention during the pandemic, since most COVID-19 transmission occurs through shared air indoors. There is ample evidence that smart investments in school buildings can reduce transmission of infectious disease, while also improving learning and increasing well-being for students, teachers and administrators...

Investing in indoor air quality improvements in schools will reduce COVID transmission and help students learn (theconversation.com)

@mocoboe @mcps spent $6.2 MILLION for CO2 data for 10,000 classrooms. Where is the data?

CDC now talks about CO2 monitoring as an indicator of good ventilation. https://t.co/Ph6OcYf3Cd "One potential target benchmark for good ventilation is CO2 readings below 800 [ppm]." Caveats: non-human sources of CO2 (gas stove), filtration removes particles not CO2. HT @citlanx

— Linsey Marr (@linseymarr) June 9, 2021

Board of Education Award Co... by Parents' Coalition of Montg...

Ventilation and filtration reduce exposure.

Ventilation and filtration reduce exposure.

Masks reduce exposure.

COVID infection risk is a probabilistic function of exposure.

So lower exposure = less infection.

These are facts.

We can debate policies, tradeoffs, significance of infection, etc. But facts are facts.

— Jon Levy (@jonlevyBU) October 15, 2022

Filtration, checking ventilation levels, masks, outdoor eating, and mobile vaccine clinics could help for flu, covid, and RSV.

Filtration, checking ventilation levels, masks, outdoor eating, and mobile vaccine clinics could help for flu, covid, and RSV. @Kelly4LASchools @NickMelvoinBD4 @Jackie4LAkids @ScottAtLAUSD we don’t want 1400 students out sick in just ONE school here in LA too. https://t.co/fTnZWwopgt

— LA Parents for COVID-Safe Schools (@LAParents1) October 16, 2022

COVID-19 Outbreaks Increasing in @mcps Classrooms. COVID Transmission Rate in Montgomery County is SUBSTANTIAL. #COVIDisAirborne

In an October 14, 2022, notice to MCPS families, the MCPS Medical Officer announces that there has been an increase in classroom outbreaks of COVID-19.  

The Medical Officer, Dr. Patricia Kapunan, fails to mention in her announcement that Montgomery County is currently at a rate of SUBSTANTIAL COVID-19 transmission.  

Dr. Kapunan never mentions in her announcement that COVID-19 is transmitted through the air and that ventilation and masks can drastically cut down on transmission.  In fact, Dr. Kapunan never mentions ventilation at all in her announcement.  

Dr. Kapunan also ignores that MCPS supposedly contracted with a company this summer to monitor indoor CO2 levels in all MCPS classrooms.  Was that contract completed? Is the monitoring of CO2 levels in classrooms in place?  

What is the purpose of a MCPS Medical Officer if they are not paying attention to an ongoing pandemic and not pushing the Board of Education to do everything in their power to keep staff and students safe?   

***************************************************

IMPORTANT MESSAGE
FROM THE MCPS SCHOOL SYSTEM
MEDICAL OFFICER

---

Dear MCPS Community,

Last week, we saw an increase in classroom outbreaks of COVID-19. While the overall Centers for Disease Control and Prevention (CDC) COVID-19 Community Risk Level is LOW for Montgomery County, we should remain vigilant about preventing the spread of COVID-19, as well as other respiratory viruses, including influenza and RSV. There are a few things we can do to promote health in our school community:

1. Continue basic health hygiene practices. This includes good hand-washing, respiratory hygiene (covering coughs or sneezes), cleaning and disinfection of shared surfaces, and staying home when sick. These actions are more important than ever, going into cold and flu season, and as we spend more time together indoors.
2. Prepare for the upcoming flu season. We are already seeing cases of influenza in the United States. Experts predict more cases of flu compared to last year, when safety measures for COVID-19 that also prevent flu were more common, and because we may have less shared immunity after a couple of lighter flu years. Basic health hygiene practices help prevent flu. The flu vaccine reduces the risk of getting the flu and having severe symptoms from a flu infection. It is available for free for anyone older than 6 months, and is especially important for people at increased risk for flu complications.
3. Continue to help prevent the spread of COVID-19 in our school community.
• Vaccination is still our most effective tool for preventing serious complications, hospitalization or death due to COVID-19. The new COVID-19 boosters are designed to protect against the latest Omicron subvariants and are available at county-sponsored clinics including school-based vaccine clinics, or at retail pharmacies or other locations. As the benefit of vaccines can decrease over time, boosters are especially important for people at increased risk of complications due to COVID-19.
• Staff and students should undergo COVID-19 testing if they develop possible symptoms of COVID-19, or after a suspected or confirmed exposure to a close contact with COVID-19. Please report all positive test results for staff and students by using the MCPS online tool and follow CDC guidelines for isolation and exposure.
• At this time, wearing a mask in MCPS buildings and facilities is optional, unless required by quarantine and isolation guidelines. Temporary masking and testing are used to prevent further spread when outbreaks are identified at school, as an alternative to home quarantine. We continue to consider other options when individuals cannot safely or consistently wear a mask in these situations. Our community also supports all individuals who choose to wear a mask at any risk level for their own health reasons, or to protect another person.

We continue to monitor health data trends closely at the county and district level with our public health partners. Thank you for your help in keeping our MCPS community healthy and ready for in-person learning, and for a wonderful school year together.

Sincerely,

Patricia Kapunan, M.D., MPH
MCPS Medical Officer

Are you looking for a quick and easy was to explain the steps necessary for safer indoor environments? Here it is.

Are you looking for a quick and easy was to explain the steps necessary for safer indoor environments? Here it is. A collaboration between the engineer @joeyfox85 and the artist @calgaryhester. Thanks https://t.co/nUZoCombuY

— Jim Rosenthal (@JimRosenthal4) September 20, 2022

Way to go Berkley Public School District!

Another public school system has a real time IAQ dashboard that displays room level IAQ parameters!https://t.co/rBGvMLUdIs

Way to go Berkley Public School District! pic.twitter.com/5LSDchM6Ri

— Dustin Poppendieck (@Poppendieck) September 20, 2022

How's the air quality in Quebec schools? Here's what we found

As fall approaches, the Montreal Gazette visited several everyday places to see how CO2 levels compare to those measured in classrooms.

...Teachers submitted readings higher than 4,000 ppm on six occasions, all from different schools. The highest reading, 4,941 ppm, was recorded in a private high school classroom in the Laurentians. The lowest, 406 ppm, was taken in a high school on the South Shore.

Drouin has urged the government to release the raw data behind the C02 measures it tracks, arguing that basing decisions on averages doesn’t make sense.

“If one afternoon, a classroom is at 4,000 ppm, it’s in that moment that you could be at risk of catching COVID,” Drouin said. “Of course, there will be peaks and valleys, but it’s the peaks that are most important. Because that’s when you’re breathing other people’s air.”..

How's the air quality in Quebec schools? Here's what we found | Montreal Gazette

Installing air filters in classrooms has surprisingly large educational benefits

$1,000 can raise a class’s test scores by as much as cutting class size by a third.

An emergency situation that turned out to be mostly a false alarm led a lot of schools in Los Angeles to install air filters, and something strange happened: Test scores went up. By a lot. And the gains were sustained in the subsequent year rather than fading away.

That’s what NYU’s Michael Gilraine finds in a new working paper titled “Air Filters, Pollution, and Student Achievement” that looks at the surprising consequences of the Aliso Canyon gas leak in 2015.

The impact of the air filters is strikingly large given what a simple change we’re talking about. The school district didn’t reengineer the school buildings or make dramatic education reforms; they just installed $700 commercially available filters that you could plug into any room in the country. But it’s consistent with a growing literature on the cognitive impact of air pollution, which finds that everyone from chess players to baseball umpires to workers in a pear-packing factory suffer deteriorations in performance when the air is more polluted.

If Gilraine’s result holds up to further scrutiny, he will have identified what’s probably the single most cost-effective education policy intervention — one that should have particularly large benefits for low-income children...

https://www.vox.com/2020/1/8/21051869/indoor-air-pollution-student-achievement

Kids need fresh air to learn. This is known. Fresh air improves cognitive function. This is known. Your kid’s classroom probably does not have fresh air, and easily could.

Kids need fresh air to learn. This is known. Fresh air improves cognitive function. This is known. Your kid’s classroom probably does not have fresh air, and easily could. pic.twitter.com/2UTSVX9Vnn

— Joe Oliver (@joeolivermd) August 27, 2022

Equivalent CO2 - A New Invention I've been working with @KashPrime on the Raven Clean Air Map. https://ravenapp.org/cleanair We want to use CO2 to assess our risk of airborne transmission, but monitoring CO2 has a bunch of limitations. Is there any way we can address them?

Equivalent CO2 - A New Invention

I've been working with @KashPrime on the Raven Clean Air Map. https://t.co/RulXcH0D4T
We want to use CO2 to assess our risk of airborne transmission, but monitoring CO2 has a bunch of limitations. Is there any way we can address them?

1/11 pic.twitter.com/GluJFfq9SN

— Joey Fox, P. Eng, M.A.Sc (@joeyfox85) August 23, 2022

Biden Brings His Own Ventilation to @mcps High School #COVIDisAirborne #CO2

On Thursday, August 26, 2022, President Joe Biden held a rally in the gym of Richard Montgomery High School in Rockville.  Montgomery County is currently in a period of HIGH COVID-19 Transmission with a Positivity Rate of 11.65%. What's a President to do with a potential super spreader event?  Why, bring his own ventilation, of course!  

Take a look at the air handling units that were added to the outside of the Richard Montgomery High School gym for President Biden's rally.

How do MCPS students that use this gym year round get the same type of ventilation upgrade for their use of this space?  

Here’s the other side of the wall. Look what they have to do to cool that Rocket air! 🚀 👊 pic.twitter.com/TIlaLxZeOt

— Jeremy Koenig 📚 (@KoenigRMHS) August 25, 2022

Meanwhile, MCPS parents continue to advocate for the Board of Education to acknowledge that #COVIDisAirborne.  The President of the United States gets it, why doesn't the Board of Education get it?  

**So in 2022, @mcps takes a hard pass on ventilation/air purification upgrades but leans in on "respiratory etiquette"**

So in 2022, @mcps takes a hard pass on ventilation/air purification upgrades but leans in on <checks notes> "respiratory etiquette" pic.twitter.com/9s7l2auyEa

— Lloyd Matthews (@Mlloyd_2010) August 25, 2022