Moving air in a good way.

Everything in medicine has ups and downs. Look at masks. No, I am not going to get into data about masks, I am just going to point out that despite the simplicity there are very real negatives: they are a pain to wear, they reduce social connection in a time of isolation, and because things have become politicized, they are now – like it or not – divisive. These are very real negatives and they are adding to our misery in a relatively miserable time. But so long as our treatment options are limited, anything we can do to help our situation with fewer negatives is a good thing.

This virus spreads in the air. We know that. And now we also know that asymptomatic people – people who are not coughing and hacking – these folks can still spread the virus to without even knowing it to others who don’t realize they are at risk. This is one of the reasons I worry about masks, because this is the very setting that regular masks are the least effective (but I promised I wouldn’t talk about that so let’s move on). 

It spreads in the air, and that makes air a big deal. What if we could reduce the amount of virus we are exposed to? Isn’t that the whole point of masks? (OK! I’ll let it go…)

There is a reason that the virus doesn’t spread well outside: it is quickly dispersed in the moving air. The further you are away from other people, the more the virus is diluted as it floats around. But inside, especially in a small, closed space, virus can linger and concentrate. We have all heard the examples of dozens of people being infected on a plane or some similar closed space. Many don’t realize that the air management in hospitals is very deliberate, with high turnover rates and everything being filtered and exhausted to the outside as opposed to being recirculated. But your house? Just the opposite: we try to keep air trapped so that it is efficient to heat and cool. Schools? The air management in many schools combined with the usual practice of keeping windows and doors closed is keeping me up at night.

I give you the fan.

I’ll also say this wasn’t my idea. Both Ferrari and McLaren are building cars with “virtual” windscreens. No, these are not your average grocery getters (both have 7 figure price tags) as these cars don’t have roofs at all or any type of windshield. Instead, they use directed airflow to divert the wind around the occupants. And if it works for them, why can’t it work for you and me?

Am I sitting here and claiming that fans are the cure for COVID? No. But reducing viral load in any way is a good thing. If we can do this with minimal side effects and help mitigate the risks of things like sitting with friends at a restaurant or teaching kids in a school classroom, then it’s a really good thing. So, why not use the same advanced tech that McLaren and Ferrari are using to better protect ourselves?  

If I am teacher in a closed classroom and a kid in the back is slowly shedding virus, that’s a bad thing. If that virus just hangs in the air, the amount is concentrated, even if they are across the room. Think of a smell. (No, not that. You are so juvenile). Think of a smell like paint. An open can of paint can slowly fill a closed room with fumes that can become progressively noxious, which is why you are supposed to make sure wherever you are painting is well ventilated.

With a simple fan, I can create a very effective “virtual” screen by creating a flow of air in front of the teacher, reducing their exposure. It’s actually a real thing, the industrial term is “air curtain.” A small fan on a table in a restaurant could protect people on one side of the table from those on the other and help keep the air moving, diluting any virus, no matter where it is coming from. The trick is to use the fan like a virtual shield – a virtual mask, as it were – by creating a perpendicular flow between people who might have a virus and people who don’t want to catch that virus. Resist the tendency to point the fan right at yourself, the idea is to make a barrier of moving air.

How effective could this be? Quantification of something like this – assigning real numbers like you have a clue – is completely unscientific, as there are many variables. But without question it would reduce people’s exposure, and any reduction is a good thing.

The more important question: what are the downsides? And this is the big upside: virtually none, and certainly less than masks. Plus, nothing says you can’t wear a mask in addition. It’s cheap, it’s safe, it’s easy, it allows anyone to more safely do something that many feel is quite risky right now.

While restaurants are tricky because you are talking about a huge variety of spaces all laid out completely differently, classrooms are pretty standard: a teacher in front of a group of kids. Setting up a $20 fan that creates a barrier of moving air between the teacher and the students is simple, effective, and with virtually no downsides. Don’t aim the fan at the desk and blow all of the papers that aren’t weighed down by apples and yard sticks all over the room, direct it across the space in between the teacher and the students (see the amazing diagram – it’s completely to scale – at the bottom). Even better would be keeping the door open and directing the air out, potentially with an open window to create a cross breeze.  It doesn’t have to be a gale-force wind, just steady movement.

Here is case study that is easily as good as some I have seen in peer-reviewed journals of late.

Not teaching kids is not an option. The success of our society depends on the education and growth of our next generation. We are social beings, and limiting our face-to-face interactions is not sustainable, no matter the risks. Anything we can do to reduce the impact of this disease while we work to regain the things that make us human are worth the effort.

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