Experimental Verification of the Particle Blocking Feature of Nasal Hair.

Although it is well known that nasal hair keeps particles from entering our body, its quantitative evaluation has not been done. In this study, the particle blocking efficiency by nasal hair was studied both experimentally and numerically. The results of laboratory experiments performed with the successfully reconstructed artificial nose indicate that nasal breathing is effective in blocking particle (especially the giant particle lager than 5 µm), especially during the exercise respiration mode. At the exercise respiration pattern, two kinds of coarse particles (i.e., particles of 2-5 µm and >5 µm) showed a continuous decrease in particle blocking efficiency (E_pb (%)) with increasing breathing duration. All curves drown by the theoretically calculated particle cut-off efficiency of nasal hairs (E_integ.) with three different thicknesses (i.e., 50, 75, and 100 µm) show a minimum (nearly zero) for the particle ranged from 0.004 to 0.4 µm. In the E_integ. curves, the thinner nasal hair can block particles more efficiently through a whole particle size range. [ABSTRACT FROM AUTHOR]