Isn’t a major point of purifiers to get rid of pollutants, including tiny particles, that gradually but cumulatively damage respiration over long-term exposure?
Yes, and all of this should apply equally to PM2.5, though on small (<0.3 micron) particles MERV filter efficiency may be lower (depending perhaps on what technology they use?). Even smaller particles are easier to capture due to diffusion so the efficiency of a MERV 13 filter is probably over 50% for every particle size.
Isn’t a major point of purifiers to get rid of pollutants, including tiny particles, that gradually but cumulatively damage respiration over long-term exposure?
Yes, and all of this should apply equally to PM2.5, though on small (<0.3 micron) particles MERV filter efficiency may be lower (depending perhaps on what technology they use?). Even smaller particles are easier to capture due to diffusion so the efficiency of a MERV 13 filter is probably over 50% for every particle size.