Filter Paper Studies VIII Effect of Asbestos Fiber Treatment
Abstract:
This is an interim report describing laboratory studies for the period of July 1, 1949 to June 30, 1950 on Blue Bolivian and Canadian chrysotile asbestos fibers as related to Navy gas-mask filter materials. The base-carrier fibers used were AA Fiberglass, cauterized-viscose rayon, and cauterized-kraft wood pulp. The use of asbestos of small-sized fibers, as contained in mill white water, results in less efficient filters than asbestos of larger-sized fibers. Filter efficiency is raised by increasing concentrations of Blue Bolivian asbestos, but it is reduced by increasing concentrations of Canadian chrysotile asbestos. Distribution of asbestos fibers in a filter is shown to affect its efficiency. Studies on the effects of calendering, high and low furnish consistencies, air resistance, and the pH of the furnish were also conducted.