The N95 (or National Institute of Occupational Safety and Health) mask is designed to protect the wearer from particles greater than 0.5 microns in diameter, while the KN95 (or Kenmore) is designed to protect against particles less than 2.5 microns in diameter, which are more likely to cause problems for people with asthma or allergies.
These differences are important for two reasons: first, because filters can only catch so much particulate matter before becoming saturated; second, because both filters and masks help reduce the amount of particulate matter that enters your body.
N95 masks are made of 95% or greater protection against the most common airborne diseases, while KN95 masks are made of 95% or greater protection against the most common airborne diseases and provide added protection for the wearer against inhalation. N95 masks provide higher levels of protection than other types of masks, but they often have a more restrictive fit and are not as comfortable to wear for long periods of time. KN95 masks offer better airflow and comfort.
N95 masks are also known as 'half-face' masks because they cover only half the face, which may cause discomfort when wearing them for prolonged periods of time. They can be less expensive than full-face masks, but they may not provide as much protection as full-face masks.
KN95 masks are also known as "full-face" masks because they cover all of the face, which makes them more comfortable to wear over long periods of time. They can be more expensive than N95 masks, but they usually provide better protection against airborne viruses and bacteria.
