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Brownstone Institute - Filtration of Rooms Didn’t Work Either

Room Filtration Didn’t Work Either


Journalist David Zweig spotted an interesting paper released by the British Medical Journal. It concerns the effectiveness of HEPA filters in classrooms as a means of slowing or stopping the spread of Covid. The study looked at German kindergarten classrooms with and without the system and concluded there was no difference. 

It’s not a surprising conclusion, once you think about it, simply because Covid is spread, if it is contracted at all, the way such coronaviruses are spread, namely through person-to-person aerosols. The major global efforts at “purifying” everything in sight was largely a waste, virus-control theater to give authorities something to do and a way to keep people hopping around like wallabies to avoid the invisible enemy. 

So while the study’s conclusions are not surprising, they are still interesting. The reason is that though I’ve been writing on this subject for four years, I had completely forgotten about the air-cleaning craze. As compared with other methods of “slowing the spread,” filtration seemed like the least controversial and the most intuitively likely to lead to some measure of success. 

Looking back, the installation of huge new systems for clearing air was a big issue at the time. Very likely, many companies got rich doing it. Certainly everyone thought it was necessary as part of the grand mitigation strategy. 

After all, recall that schools couldn’t reopen until they had installed new systems else teachers would suffer and die. So we were told. So kids and teachers plus administrators just had to wait it out. There were germs living in those classrooms and they had to be thoroughly cleansed! 

The New York Times wrote the following on November 18, 2020. Having celebrated the magical disease preventing properties of filtration systems, it concludes the following:

Even if you decide to use an air purifier as a protective measure, we recommend that you also continue to closely follow the CDC’s other longstanding advice, including social distancing, wearing a face covering outdoors, washing your hands frequently, and treating frequently touched surfaces with disinfectants. As the CDC writes: ‘The best way to prevent illness is to avoid being exposed to this virus.’

As in: dismantle the normal operations of society until the authorities tell you otherwise. 

Yes, you remember those days. Let’s say you have installed a new HVAC system. That’s good but it does not quite do the trick. You still must stay away from everyone. You have to mask up, outdoors even. You have to wash your hands constantly. You have to spray everything down with sanitizer. I mean, it seems like your whole life is consumed by fear of disease. 

It’s a wonder that anything else got done at all. It was the life occupation of everyone on the planet. And this was before the vaccine arrived, after which you have to still do all the above plus take the shot. No matter how many layers of protection you pile on, it is never enough. 

Crazy, right? But those were the times. I have a friend who directs a boys’ choir in the UK, one part of a choir school that has continued operations for hundreds of years. Suddenly the lockdowns came, silencing the singing for the first time since Queen Elizabeth I. 

This was a major problem for the choir. They cannot just take off months because the voices at that age are constantly changing and they need help through the shifts. Incidentally, this was a major problem for childrens’ choirs the world over. It doesn’t quite work on Zoom. 

As a result, the director raised money quickly to install large filtration systems in the practice and performance space. He was investigated by public health authorities. He eventually persuaded them to let his choir meet and sing but only in masks and with distancing, and so on. What made the difference was the filtration system, which, as it turns out, does not seem to make any difference in terms of infection rates. 

How much money was spent globally on such nostrums? Countless billions no doubt. And yet it was presumed to be incontrovertibly true that this worked to deter viruses in the room. In the models, they did and the papers published at the time all said this. So in the name of virus control, it entered the list of must-do things to achieve the great goal of exterminating this virus once and for all. 

If you can believe it, the page at the CDC strongly suggesting this upgrade is still public on the website, justified in the name of controlling Covid, all with very detailed instructions because, after all, being indoors is dangerous (and so is being outdoors!). The last change to the webpage was February 2023, but no real challenge to this has emerged so it stays up there. 

It’s all quite extreme. “When possible,” they say, “aim for 5 or more air changes per hour (ACH) of clean air to help reduce the number of germs in the air.” And they offer this helpful bit of science to assist in measuring the ability of a system to get rid of Covid.

Have you taken that measurement in your own room? If not, you might be contributing to the spread of the bad bug! 

There was a real sense in which people once believed that Covid floated around rooms like a miasma. In late 2020, I entered a wine bar and ordered. They gave me a cup and told me to stand outside. I asked why I couldn’t sit in that room over there. The lady said “because of Covid.”

“You think Covid is in that room?”


I guess they hadn’t installed HEPA filters yet. 

Air ventilation was part of what was known as the “swiss cheese” model of avoiding infection. No, nothing works perfectly. Everything has a hole or two or more in it. But when you stack them together, you eventually get a solid such that nothing can get through. 

Doesn’t sound very scientific. 

Looking back, it’s clear that the main reason that the CDC seized on this topic was to add to the protocol for disease panic – yet another thing we were supposed to do in order to realize the great goal of stopping the spread of a virus that everyone got in any case. 

Remember Deborah Birx? She was head of the White House Covid task force. After she resigned when Biden took charge, she immediately went to “work” for ActivePure, one of many companies that was lobbying for a piece of the funding from government that was set to install filtration systems in every public school. 

How much funding? The federal government dished out $122 billion for schools and $350 billion for state and local government. In other words, mind-boggling numbers. All of this without any evidence of real-world effectiveness against virus spread of course. 

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  • Jeffrey A. Tucker

    Jeffrey Tucker is Founder, Author, and President at Brownstone Institute. He is also Senior Economics Columnist for Epoch Times, author of 10 books, including Life After Lockdown, and many thousands of articles in the scholarly and popular press. He speaks widely on topics of economics, technology, social philosophy, and culture.

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