As the co-founder of Restore Childhood, I fought against mask mandates (even with a parody video—SEE ABOVE) with everything in me! We launched this fight because we saw children—our most vulnerable—bearing the heaviest cost of policies that crumbled under scrutiny. That’s why Restore Childhood is funding research like the study you’re about to read about: to reveal the truth and shield kids from unscientific overreach that robs them of their childhood. This matters—it dismantles the flimsy assumptions behind mandates, arming us with hard data to protect their lives and freedoms going forward.
School closures hurt kids the most during COVID, but masking them was especially tough. While adults could ditch masks in spring 2021 after vaccines got emergency approval, millions of kids had to keep wearing them until June 2022. Even after the CDC said masks were optional on Feb. 25, 2022, the Biden administration forced the youngest kids in Headstart programs to stay masked until a judge stopped it on September 20, 2022.
Figure 1
Source: Dashboard, data from CDC, Burbio, and NCES (data sources accessible via link)
Masking kids—especially seeing toddlers outside with masks while teachers went mask-free in late 2022—felt wrong to many. That’s why Restore Childhood funded a study to figure out why masks didn’t seem to stop COVID as promised. The study started in 2021, and its results first appeared online in a pre-print server in December of 2023. They have now been published in a peer-reviewed journal.
We didn’t tell the researchers what to find—we just asked them to dig in.
The study built on a 2021 mask study completed by researchers at the University of Waterloo in Canada. This time, Dr. Ram Duriseti, an unpaid Restore Childhood board member from Stanford, co-authored the study with the University of Waterloo researchers.
Other studies since have found similar things, which is encouraging.
You can read a detailed breakdown by that that our friend Emily Burns wrote for her own Substack along with all sources. But if you want the short version, keep reading!
Source: Mechanistic investigation of fitted mask source control efficacy for sub-micrometer aerosols. Accepted peer-reviewed, here. Dec 2023 pre-print available here.
What’s This Study About?
This study asks: Why do some studies say masks stop COVID, but real-world results say they don’t?
The authors point out, “population-wide adoption of masking has not provided a concordant curbing of disease spread (Centers for Disease Control and Prevention 2021; Schauer et al. 2021).” Back in 2020, the CDC noticed this gap too and called for more research.
This study steps up.
Most mask studies use mannequins to test how well masks block big particles (5+ microns). Problem is, COVID travels in much smaller particles—about 0.28 microns, like cigarette smoke. These tiny aerosols carry most of the virus (87%-100% in studies), especially in the 0.25-0.5 micron range.
Older studies ignored this size, but this one tests masks against these smaller, virus-carrying particles (0.2-1 micron).
Excerpt 1
LH image source: Characterization of Exhaled Particles from the Healthy Human Lung—a Systematic Analysis in Relation, Schwarz et al; RH image source: The Size Distribution of Breath in the Exhaled Breath of Healthy Human Subjects, Papineni and Rosenthal
What Did They Find?
Here’s how well masks block those tiny 0.2-1 micron particles:
Surgical masks: 6%-40% effective
KN95s: 24%-54% effective
N95s: 52%-82% effective
Excerpt 2
So, Do Masks Stop COVID Spread?
Not really. Here’s why:
COVID spreads like smoke—super tiny, super numerous particles. You only need about 100 viral particles to get sick, but a sick person breathes out millions per hour—up to 10 million, enough to infect 100,000 people!
Even if an N95 blocks 80% of those particles, you’re still surrounded by thousands of invisible “doses.” A surgical mask blocking 20%? Forget it—12,000 doses instead of 15,000 doesn’t save you. It’s like smelling smoke: fewer smokers in the room don’t mean you won’t smell it.
Plus, some people breathe out way more virus than others—up to 30 times more! Even with an N95, a “super spreader” could still release 90,000 doses per hour. Studies show 3.5% of people create over 50% of the aerosols. Sick people, especially older or weaker ones, pump out the most—and the smallest, most dangerous particles (<0.3 microns) make you sicker than bigger droplets.
These tiny aerosols float around forever (well, at least 3 hours) and stay infectious. You could get sick in minutes just being near someone—or even after they leave the room.
The Big Picture
This study shows masks aren’t great at stopping the tiny particles that carry COVID. That explains why masked and unmasked school districts had similar case rates, or why Germany’s different mask rules didn’t change much:
Figure 2
Source, @IanMillerSC, using data from the Robert Koch Institute
This research could help end mask mandates for good by showing they don’t work as well as we thought. It’s a starting point for more studies—and a reality check.
Great article, Emily! Sadly, the negative impacts on child development that occurred during that time will be felt for years to come.
No studies that show masks don’t work will stop blue politicians from mandating them.