Masks don't work??

Recently, CDC released a study that, among other things, seems to point out that 85% of COVID-19 positive patients wore masks "often" or "always". Just going by this alone would seem to point to the conclusion that masks don't work. However, here are a few remarks that should be considered as well,

- Could it be that the masks used by these people be inadequate in protecting them? After all, since most people only have cloth coverings or untested masks to rely on, what else can they be using?

- Other countries, particularly in places where mask products have matured past the basic cloth and untested disposables like those available here in the US, do not show the same conclusions. Some of these countries even have higher population densities than we do here, yet they are not experiencing the surges like the US and most of Europe. Could the availability of higher performance masks (instead of fashionable cloth coverings or the lowest priced 3-ply masks) help control the infections or even help lower the inoculum to where the population is less sick or even asymptomatic?

While I am not nearly smart enough to be a doctor or be in the medical field, I know that there are differences in mask qualities. These qualities are what allows those in healthcare to survive, even doing what they are doing. The most important mask quality is the PFE (Particulate Filtration Efficiency), which is the filtration performance tested from the outside to the inside of the mask (protecting the wearer). This test involves the filtration of particles less than a micron (0.1 - 0.3 micron), which is the virus level. The masks and respirators approved for medical-grade are required to be filtering at least 95%. Some, like those we have, are tested to over 99% in sub-micron efficiency.

Since the PFE is such a coveted measurement, any brand or manufacturer of masks will market this achievement (if they are honest). However, most masks available (almost all in Amazon) don't have PFE (not to be confused with BFE) either tested or meeting over 40%. The European medical mask standard (EN14683) does not even require PFE tests, which is the standard to get CE. The Chinese civilian mask (GB/T 32610) does not need PFE as well, yet this is mostly what is available in the US. The Chinese's highest standard for a medical mask (YY 0469) requires PFE of at least 30%, but these are seldom found in the US because they can't make enough of them to be exported.

You may ask, why are the good masks not available here in the US? Here are my thoughts on the reasons,

- The US has never needed face masks on such a scale. So there was no meaningful stockpile or inventory, to begin with.

- Most US brands outsourced their mask productions (how else could we get US medical-grade masks?).

- Mixed messages from the government about masks, including using cloth masks for such a contagious virus. This could be inexperience and not knowing enough about the virus.

- Censorships by private and governmental entities that leaves only non-medical and cloth masks be marketable. This suppressed the availability of tested and high-performance masks that are actually in abundance after months of production ramping.

In conclusion, do masks work? Yes, masks do work, as proven by frontliners, and other countries. This is provided that they are good enough in quality, especially with regard to PFE. Look for masks that are ASTM 2100 Level 2 or 3 and have FDA 510k approval (medical-grade confirmation). When the situation calls for respirators (poor distancing and high airborne concerns), look for FDA-approved respirators listed in the latest EUA.

To verify surgical masks on the FDA database, go to

and enter the manufacturer name.

To verify respirators on the FDA EUA Appendix A list, go to

and scroll down to Appendix A, then look for the manufacturer and the model of the respirator.

Let's do our part by living our lives safely!

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