N95 respirator masks are designed to prevent the inhalation of airborne particles. They also block droplets, splashes and sprays of liquid from entering one's nose and mouth.
N95 masks are designed to seal one's face such that most of the air that one breathes in has to go through the filter and not through the gaps between the mask and the face.
Haze particles are predominantly made up of fine particles that are 2.5 microns or smaller (PM2.5). Studies have shown that N95 masks do provide good protection against the haze as they are at least 95% efficient against fine particles that are about 0.1 – 0.3 microns. It is even more efficient (99.5% efficient) against particles that are 0.75 microns and larger.
Elderly people, people with chronic lung disease, heart disease or stroke, and pregnant women should consult their doctor on the use of the N95 mask if they feel uncomfortable while breathing. N95 masks are not certified for use on children, so children should remain indoors as much as possible when the PSI level is high.