A Guide To The Masks That Work

   Which mask ?




N95

The United States National Institute for Occupational Safety and Health (NIOSH) has standardised N95 face masks. The “N” stands for “not resistant to oil,” while “95” represents its minimum 95 percent filter capacity for catching viruses as small as 0.3 The N95 respirator reduces the wearer's exposure to tiny, invisible particles in the air, including bacteria  and many viruses. Some N95 type masks have an attachment, an exhalation valve, which smoothes the exhaling and decreases humidity, heat and moisture from the inside.

But for Covid-19 patients or suspects, the N95 attached with an extension is not an ideal choice since they need to use one without an exhalation valve so that their cough or sneeze droplets are blocked inside the mask. 
There are some other standardised face masks by NIOSH that are N99, N100, which claim to filter 99 and 99.97 percent of airborne particles, respectively.
There are also R and P series which differ from N in terms of their resistance to oil. R and P are respectively somewhat and strongly resistant to oil.

Face Filtering Piece (FFP) 
Face Filtering Piece (FFP) face masks are a rage in Europe. They are divided into three categories, FFP1, FFP2 and FFP3. According to the European standards, each type can filter 80, 94 and 99.95 particles down to 0.3 microns. They are equivalent to N95 in Europe.

EN 149:2001+A1:2009 represents the most recently accepted and current standards by the European Committee for Standardization (CEN).
FF1 type is the lowest level mask for the protection. Generally, people who have respiratory diseases use FFP1 to avoid being affected by dust and similar substances. It can't keep the coronavirus at bay, however, as it is exclusively meant to be against toxin-free dust.

 The medium level mask, FFP2, provides additional protection from chemically-laced air particles and dust. It's uncertain whether it can provide full protection from Covid-19.

When it comes to FFP3, it ensures the highest protection according to CEN standards. It is the most effective mask against the coronavirus.

Surgical masks are generally used to protect the wearer from large-particle droplets, sprays and splashes. It also prevents potential infectious respiratory secretions to others. However, it is considered to be weak against the coronavirus.
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