Medical Masks

The mask regardless of type is designed to block and restrict moisture, droplets and germs from leaving you and entering the local air space.  It will not block all things but it will reduce amount that moves into the air and by doing this reduces the amount of germs hanging in the air until the moisture falls to the ground.  The viral load is a reference to the amount in any given area so more is worse and less is better.  Hypothetically if you have 10,000 per droplet and your mask absorbs 90% of the droplets you reduce the amount you will breath out to a much lower amount or approximately 9/10ths of the original exhalation.  The concept is that your body may be able to handle the lower viral load (amount) but a higher amount will overwhelm your immune system and allow the parasite to grow and give you symptoms or worse. 

The mask also works in reverse by blocking the moisture and some floating particles, not all, from being breathed in through normal respiration.

Most medical masks, by design, have a  good to excellent rating as to blocking bacteria and resisting moisture degradation.  The ratings are designed to go from ASTM 1 to ASTM3.  The level 1 being designed for normal low risk situations and the level 3 being designed for higher risk applications and high moisture procedures.  This is needed because many medical procedures push fine droplets into the surrounding air and as the day wears on that moisture can weaken the layers exposed causing the mask to degrade.

All of this only works if the mask fits tightly and there is no air by passing the filter media. Experts who live by the mask often tape the sides or bottom to obtain a good fit and ensure all of the air is filtered.

Mask are often used to prevent the spread of a pathogen between patients or healthcare providers because it blocks the exhalation of the pathogens.  Respirators are designed to protect the wearer from out side particles or pathogens entering their body through their lungs. 

The N95 is a very specific piece of PPE, Personal Protective Equipment, and it is designed to fit tightly and block  95% of all the particles 0.3 microns or larger.  It is widely used in industrial settings where there is exposure to environmental hazards.  It's value in medicine is that it will reduce the exposure in high viral load situations.

The longer you are going to wear the mask the more comfortable it needs to be.  This is often a trial and error personal experience.  You have to buy the mask then wear to know how well it fits and how comfortable it is.

All masks claim to be made of materials that will not cause skin reactions but no one I have read makes any claims in this area.

The three types of straps, earloops, behind the head or ties.  Most everyday people opt for the earloops because it is simple and works.  Most surgeons prefer the ties.  Most N95s are behind the head style because they are designed for a tighter fit on the face to eliminate any air bypassing the mask around the face or chin.

The anti-fog style is designed with a little extra foam or tighter fitting nose area so as you breath out very little to no breath shoots up towards your glasses.  I have only tested one mask a Halyard Anti-fog which was excellent at preventing the fogging and it did have an additional foam strip inside of the top of the mask.  

Vents or exhaust ports are designed to allow for easier or less effort breathing out.  The downside is that there is no exhaust filtering so if they are sick they will exhaust pathogens.  You are only protected breathing in.  This is designed for industrial work where pathogens are not the issue and the person welding, grinding or doing other work needs to ability to breath our easier.

Activated carbon is used in some masks to absorb odors or toxic gases.  Keep in mind it has a limited value.  Basically you take processed carbon which has open surface area that will bind and hold toxins.  However, you have two issues the speed at which the air moves over the surface and how much of the processed area is available or open to attracting the toxins.  In simple terms it has maximum effect when you start using it then goes down as the carbon surface area is covered with other molecules.

Nano masks are new to the market and are based upon the idea that the openings are much smaller than previously used materials.  Keep in mind it is the opening in the material that determines the size of object that can pass through it.  The smaller the hole the smaller the object that can pass through it.

Reusable and or washable masks.  It is possible to have a washable mask.  If it is designed for X number of washings then follow the instructions and the material should stand up under the washings.  Other materials that offer enhanced levels of protection may or may not stand up because the chemicals in the soap may degrade silver, charcoal or other added materials.  However, if you stick to the recommended treatment and handling you should be OK. 

A final thought would be to fit the mask to the task and your face.  If you succeed it will serve you and do all a mask can do. In your mind always hold the expectation of your health and wellness as your ideal and let the mask simply serve you and your needs.