Research, Empathizing:

Face masks are “widely utilized for reducing inhalation exposure to airborne particles that may be associated with various health effects.” [1] In fact, they act as a barrier that protects the mask wearer from his/her surroundings, and others from the mask wearer as well. A mask serves as a filter that blocks out fine solid particles or liquid droplets in the air called aerosols. When a sick person coughs or sneezes, aerosols leave the person causing a threat to others if the particles are inhaled.[2] This makes face masks a crucial resource in preventing the spread of a virus. 

A N95 mask, which is able to filter out 95 percent of particles of all sizes from the air and protect a person from the virus, is usually made from polypropylene. Polypropylene fibers are interlaced to create layers that make it hard for a particle to penetrate. Other mechanisms such as diffusion, and electrostatic attraction exist to further ensure that particles do not get through a mask.[6]

However, contrary to popular beliefs, only wearing a face mask will not be able to protect an individual. In fact, masks  are “only for the protection of others, not for the protection of oneself.” (the guardian) “The use of a mask alone is insufficient to provide an adequate level of protection, and other methods should also be adopted,”[2] and masks that are rated lower than N95 are unable to filter out the respiratory droplets carrying the virus.

Perhaps the biggest issue with commercial face masks is that the fit of the mask can drastically affect its efficacy. It is often very difficult to form a complete seal between a face mask and a person’s face, which creates several entry points both into a person’s respiratory system and out to the person’s surroundings.