The virus is not airborne, the n95 is to prevent any possibility of an aerosolized droplet from entering your nose and mouth.
The virus IS airborne ! The percentage of droplet form to aerosol form is still unknown
One of the challenges facing practitioners, particularly in an enclosed building, is that even large-sized droplets can remain suspended in air for long periods [17]. The reason is that droplets settle out of air onto a surface at a velocity dictated by their mass [17]. If the upward velocity of the air in which they circulate exceeds this velocity, they remain airborne. Hence, droplet aerosols up to 100 μm diameter have been shown to remain suspended in air for prolonged periods when the velocity of air moving throughout a room exceeds the terminal settling velocity of the particle [17].
Another critical variable is the rate at which particles desiccate. Even large, moisture laden droplet particles desiccate rapidly. In his seminal paper, Wells showed that particles begin desiccating immediately upon expulsion into the air and do so rapidly: particles up to 50 μm can desiccate completely within 0.5 seconds [8]. Rapid desiccation is a concern since the smaller and lighter the infectious particle, the longer it will remain airborne. Hence, even when infectious agents are expelled from the respiratory tract in a matrix of mucus and other secretions, causing large, heavy particles, rapid desiccation can lengthen the time they remain airborne (the dried residuals of these large aerosols, termed droplet nuclei, are typically 0.5–12 μm in diameter [17]). Of further concern, very large aerosol particles may initially fall out of the air only to become airborne again once they have desiccated [17].
The N95 may come with 3 different functions A 1 way valve to protect the user, or the valve is reversed to protect everyone else or no valve at all. THE mask is NOT 100% effective. ( Read the warning label like you should read the vaccine label before you inject your child with poisons )
Common sense would dictate that preventing droplet expulsion at its source would be more effectual than trying to stop infection from a mask being bombarded with a combination of droplet AND aerosolized particles along with many surfaces, hands, face etc being the vectors for the disease transmission.
Getting sick from Covid-19 is serious business if you are a frontline worker and most PPE are a JOKE !!!