Protection of the Respiratory System Against Nanoparticles Inhalation

Abstract

Aerosol filtration in fibrous filters is one of the most widely used methods for high efficiency removal of fine and ultrafine aerosol particles. The technique is utilized in both traditional (e.g., steel, cement and mining) and high-tech industries, modern applications (microelectronics, opt electronics, biotechnology, pharmacy, nuclear plants, military); in the latter case, extremely high standards of filter efficiency are usually imposed. The same is true of the fibrous filters used in the respiratory protective devices (worn by surgeons, soldiers, firemen, miners, construction and farm workers), and of the laminar boxes in modern research laboratories, clean rooms, and operating rooms in hospitals. A lot of fibrous filters are also used in many daily applications, including HVAC systems in public and private buildings, filtering systems in cars, airplanes, and vacuum cleaners. A brief review of the classical single fiber theory and its possible extensions are presented first in this chapter and then specific issues related to nano-scale aspects of aerosol filtration are discussed (filtration of nanoparticles in electret filters, filtration of aerosol particles in nanofibrous media, filtration of fractal-like nanoaggregates, filtration of nanoparticles in polydisperse fibrous filters). The main objective of this work is to collect the information necessary to design efficient fibrous filters for protecting people against inhalation of harmful nanoparticles.