Evaluation and Optimization of a Flexible Filtration System for RespiratoryProtection System 21

摘要

Current filter elements for the M40 series of respirators are housed in rigid,metal canisters that contain media for aerosol filtration and adsorption of gases or vapors. The filtration media is often pleated for increased surface area. Certain harmful gases are removed by adsorption to activated carbon that has been treated with hexavalent chromium or zinc metal cations in a process known as whetlerization. Whetlerization provides active sites to chemisorb certain poison gases. The carbon is generally present as a coarse granular bed, but can also be present in a powder form incorporated in a fabric, as in the M13A2 filter element.