Masks for Airborne Viruses?
A recent report in Science Magazine (1) confirmed what Smitmask and various scientists have been observing since the beginning of the pandemic – Covid viruses are also airborne. Viruses can linger in stagnant air. This is why from the beginning, SmitMask has been advising our customers and friends to open their windows every 15 minutes. Air in a room ideally should to be changed 4 to 6 times every hour.
Ventilation systems are not always efficient enough – most were designed pre-Covid. But opening windows is a cheap and very efficient way to make sure air is changed. Windows should be open as wide as possible and as frequently as possible, and if possible, all the time.
What about masks?
The report cites that “for aerosols <2.5 μm, filtration efficiency decreases by 50% for a relative leak area of 1%” in masks. If you are in an enclosed room for an extended period of time, the only mask that almost fully protects you is the N95 worn TIGHTLY SEALED. Many people don’t wear the N95 tightly sealed, and therefore, don’t get the full protective properties of the N95.
Loose-fitting masks like cloth masks and surgical masks are not designed to be tightly sealed (surgical masks were designed to block droplets, not aerosols) and air will go in through the gaps (as with an N95 not tightly sealed) – this is a fluid dynamics principle – air will always take the path of least resistance. But if windows are open and ventilation is good, and everybody wears a mask (fabric or medical), virus spread will be greatly reduced. Multiple studies continue to show that universal masking reduces overall community spread.
Since it is hard to wear an N95 for long periods (not to mention that it’s expensive and bad for the environment), for use in regular low virus-load settings, a comfortable 2-layer 100% cotton mask is best, when keeping windows open and not staying too long in enclosed spaces. They perform better than surgical masks in humid environments (reported by The Washington Post, Smithsonian and NIST (2) ). They are soft and comfortable, and since they are made of natural fiber, they do not irritate your skin. SmitMasks have the added benefits of a unique ergonomic shape that makes them much more breathable, minimize eyeglass fog, and stop sliding around your face. Their anti-odor property further minimizes odors.
For regular daily settings wear the most comfortable 2-layer cotton mask you can find, keep it on when indoors, and make sure to open the windows every 15 minutes or as often as possible.
(1) Science Magazine, Aug 27, 2021. “Airborne transmission of respiratory viruses”
(2) The Washington Post, Mar 27, 2021. “What’s in all those masks?” Tests conducted by the National Institute of Standards and Technology (NIST) and the Smithsonian's Museum Conservation Institute.