How does my face mask work? And does it?

Covid-19 infoFace MasksNano fiber face masksSilicone anti-virus face masksN95 masksKN95homemade face masks

Aug 10

Cotton vs N95 v Nano masks
Masks allow air in so you can breathe while at the same time also preventing particles from getting through. Your basic cotton cloth mask will block respiratory droplets mechanically; the cloth physically blocks the drops that you can see if someone coughs or sneezes. This cloth barrier will also block your own droplets that are emitted when you speak, cough or sneeze, and keep them from escaping out into the world to infect someone. But there are also respiratory droplets that are smaller than those we can see. These are normally referred to as aerosols, and these will stay and hang in the air for a longer period of time. If you want to block these aerosols, you need a better filtration system. That's where respirator masks come in to the picture.

Respirator masks are ‘better’ masks. They are designed to block both respiratory droplets and also aerosols. A mask designed to do this will have a filter with several layers; at least three, and some have up to five. One layer blocks the bigger droplets, and another layer is made of a material that has what we call an electrostatic charge. This ensures that small particles which can physically permeate the filter adhere to the material so they don’t pass through to where you can breathe them in. The third layer will be close to your skin and should serve the function of wicking moisture and keeping the filter from getting wet as you breathe. Your standard N95 mask falls into this category. It's a mask that has both a mechanical droplet filter, and also an electrostatic filter so as to catch aerosols, as well as bigger droplets. It also seals well. However, the N95 norm is not a new one. It meets the goal of protecting the wearer from 95% of industrial dust, pollution and PM2.5 particles, not necessarily viruses. N95 masks were designed with short term use in mind, not the all-day, 8-hour a day wear that we can see today. The problem with a mask that works on electrostatic principle is that once the user breathes through the mask for a period of time, the electrostatic layer will become moist and the more moist it becomes, the less effective it will be, in terms of filtering capability.

Today in the age of Covid-19, we are using these high-end masks because they really do provide a very good level of protection; viruses do not travel in a straight line, and the various layers built into the mask will help to catch more of the virus than the filtering level of each layer on its own would be able to manage. So though those N95, KN95 or FFP2 masks that people are wearing to protect themselves don't actually fully protect them from the virus, they do provide a very high level of protection, as long as the user does not keep the mask on for too long. For full virus protection at 99.9%, you really would need an N99, KN99 or FFP3 standard mask, but again the same short-term use principle applies. Any mask that functions on electrostatic principle will cease to function as well as it should the moment the electrostatic layer gets wet.

Enter NANO. NANO materials are extremely tightly woven. So tightly woven in fact that they can block PM2.5 particles, bacteria and even the smallest of viruses mechanically. And amazingly, NANO material has been shown to filter bacteria, PM2.5 and viruses at up to 99% while still allowing air through. Despite its tight weave, a NANO-fiber filter is actually extremely thin; so thin in fact that paradoxically, it also allows good breathability. So a NANO-fiber respirator mask or a NANO filter will actually allow you to breathe much more easily than a traditional respirator while also giving you increased filtration, even when the filter becomes filled with moisture.

Two things in conclusion; one, if you are wearing an N95 mask to protect yourself from Covid-19, be sure to change your mask as soon as it becomes moist from breathing, otherwise you are putting yourself at risk. And two, yep, that NANO fiber filter that you put into your properly-fitting homemade cloth mask will actually give you superior filtering protection to the N95 if you plan to wear it at work all day. But…….be sure to read the caveat below:

Important: if your homemade mask (or any mask for that matter) doesn’t fit properly, you can have the best filtering system in the world and the virus will still be able to get in. Make sure your mask fits you right and seals properly. A cloth or surgical mask will never seal as well as the N95 type, but it should fit as tightly as possible while still being comfortable enough to wear. Having a nose clip on the mask will help improve the seal.  Masks with the best seal are by far Silken N95 silicone masks and standard disposable N95s and NANO N95's.

What kind of mask filters out how much of the virus? Refer to this user-friendly chart put out by the Czech Nano producer Respilon

How does my face mask work? And does it?

Which mask? N95 vs KN95 vs FFP2

What's the point of a face mask, anyway?