Tuesday, August 11, 2020

An Easy Test has been Created to Test Efficiency of Mask Types


Hopefully by this point in the pandemic, all of you reading this are well aware of the need to wear masks and, potentially, eye coverage when in a public setting.  SARS-Cov-2, the virus that causes Covid-19 can easily travel in the air between humans where viral particles from an infected individual can be easily and un-noticeably inhaled by a susceptible host.

There is also the potential for an infected individual to cough or sneeze and. potentially propel droplets containing the virus into the mucus membranes of the eye... hence the potential need for eye protection.  When I am seeing patients, I am covered quite literally from head to toe in protective gear so I'm not overly concerned about my eyes with all of the gear in place.  However, when I am not in the office I feel the need to protect my eyes... I mean, you can't be *too* careful.  I went on Amazon and found a clear lens for an Oakley "Heater" frame I had for running.  The wrap around design keeps my eyes protected without having to wear "safety glasses".  The lens did NOT come with a nose piece so I ordered one of those as well.  Basically for about $20 I had a (fairly) stylish form of eye protection.  That's just food for thought.  Here are a couple of photos.

Getting back to the original point of this post, masks are an extremely critical part of the PPE scheme whether you are in healthcare or not.  Simply strolling around Home Depot or the local Costco with no mask is exposing you and greatly increasing your odds of infection.  Of course the other side of the coin is if you happen to be Covid-19 positive and unaware yet, you could be leaving a tsunami of shedded viral particles in your wake and not even realize that you may well be infecting dozens of others.  Those others could then very well infect *more* including the potential of infecting those who have a compromised immune systems and who could be facing death from the virus... which *you* infected them with.

This isn't about personal freedoms, this is about potentially killing innocent human beings.  This is the equivalent of hunting in a field right next to an apartment complex.  You may OWN that field and it is certainly within your rights to hunt on it.  But think about this:  If you miss a deer and the round goes through an apartment wall and kills a grandmother; YOU are responsible for that.  It's not an infringement on your rights as a property holder or a gun owner.  It's about the responsibility of ending another human life.

So now,  hopefully that I have you enthused about wearing a mask to protect yourself and others, let's take a look at their effectiveness.

Some smart folks at Duke University came up with a brilliant yet fairly simple testing setup.  Utilizing off the shelf and easy to obtain parts, members of the Medical School and the Duke Department of Physics created a "black box" that allows for quick, easy, and reliable testing of different mask designs and masking mediums.

I'm not going into great detail about how to build the testing device.  Part of it involves a laser, which can be dangerous to the eyes unless you know what you are doing, so the inventors are asking that only people with laser knowledge try and build one.  The important thing here is learn what separates the reliable masks from the poor ones.

The magic ingredient seems to be 3 layers.  A variety of materials were tested including a fitted N-95 Respirator (which scored the best).  Masks with 3 layers, even those made by hand with simple cloth, provided adequate filtration.  Single layer systems, such as the "neck gaiter" worn by snow skiers and other outdoorsy types scored the worst.

So the big takeaway from today's post is that masks are important.  Masks save lives.  In order to be effective masks need to be composed of three layers.

My personal favorites for non-healthcare workers are the home crafted cloth masks that utilize a pocket.  They are a 2 layer mask with a pocket between the layers that allows the user to place a filtration medium inside the pocket between the outer and the inner layer.  In my humble opinion, the best thing to put inside that pocket is a custom cut HEPA filter.  These filters can be purchased on 
Amazon as well as Home Depot and, I'm sure, other home improvement stores.  You remove the plastic "caps" on the top and the bottom, unroll the filter, and then cut the size you need.  You can easily get *many* pieces out of a single large pleated filter.

HEPA collects 99.97% of particles that are at least .3 microns in size making them even better at filtration of the SARS-Cov-2 virus than a N-95 filter.  These large cylindrical HEPA filters are available for about $40 a piece and you can guard your entire family for months with the amount of filters you can get by cutting them up.  This is *highly* recommended.

If you are interested in the entire study that produced this post, which includes detailed descriptions on the testing device itself, that information can be found by following this link to the Science Advances website.  

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