Precipitation of low-dispersion dust particles in respiratory tract by individual protective means usage

Abstract

The authors suggested a method to evaluate quantity of settled polydispersed suspension in human respiratory tract, due to individual protective means of respiratory organs. The method includes calculation of the particles collection and their precipitation in lungs. To disperse suspended titanium dioxide particles by dimensions in occupational environment, the authors calculated number of precipitated particles in free breathing, and in breathing through hermetically and nonhermetically placed respirators. Findings are that over a half of particles measured under 100 nm precipitates in alveolar area and only one sixth of them - in upper respiratory tract. Numbers of the particles measured 100-1000 nm, precipitating in upper respiratory tract and alveolar area, are nearly equal. According to the authors, gaps with relative square near 0,1% between respirator and face result in lower protection coefficient in 3,5 times for highly dispersed particles, and nearly in 48 times for the particles measured over 100 nm. These data necessitate declared protection parameters of individual protective means for respiratory organs to be added by amendment considering its lower efficiency in real conditions.