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HYGIENIC BASIS FOR MONITORING OF PMD

A rational criterion for the hygienic relevance of the surface area of dust settling in the lungs is formulated in the article.  
The differential parameters of airborne dust are determined by measuring the mass concentration of particular matter PM10 and PM2.5. A unified model of the behavior of dust in the lungs has been developed. It describes the deposition of particles on the walls of the airways when cleaning the inhaled air and the subsequent removal of settled dust from the lungs.  
The adequacy of the model was verified by the compliance with the results of in vivo testing. The phenomenon of dust deposition in the lungs is described. It is typical for periodic dust exposure in the workplace. Dust exposure is acceptable if the surface area of the deposited dust does not exceed the area of the internal surface of the airways. With this approach, the concentration of dust in inhaled air is recomputed into the surface area of dust particles deposited in the lungs. As the initial data, the results of routine measurements of the mass concentration of particulate matter PM10 and PM2.5 are used. Permissible concentration for PM10 close to the WHO Recommendations and adopted in industrialized countries. Permissible concentration for PM2.5 should be a lot stiffer than currently accepted.  
In reality, only the pair PM10 and РМ2,5 gives a quantitative characteristic of the danger of dust exposure. It determines the entering to the area of permissible dust exposure.