On the evaluation of fibrous particles in remote ambient air

Separation of Asbestos Fibers by Length – Procedure for Obtaining Different-length Samples for Biological Experiments – [Translated]^†

“…As shown in the flow diagram of Bold Figure 1, the continuous classification apparatus used in the investigation consists of a fiber feeder (1), fluidized bed (2), wire screen for separation (4), and a virtual impactor (3). The fiber feeder (1) is of the same type as that used in our previous report 6 l which chops fibers little by little in a grinder and transfers them pneumatically.…”

“…Spumy et al 4 l made asbestos and glass fibers into fibrous aerosols by a vibrating type generator, and dispersed and separated them by sedimentation in water after a separation by elutoriator and cyclone. They reported that they were able to obtain several grams each of fine fibers containing 99% of 3 ,urn long or smaller fibers and others consisting of 100% of 10 ,urn long or smaller fibers.…”

“…They have even carried out parts of the experiments to that effect. However, Spumy et al 4 l concluded that their method involved a problem of reproducibility and needed improvements, suggesting that they could not obtain enough amount of fibers for the experiments with their methods.…”

“…On the other hand, Spumy et al 4 l indicated that in order to separate fibers by length it is most effective to use interception effects, together with the use of a uniform microsieve and to proceed in such a way that the fibers are as closely perpendicular to the flow direction as possible. They have even carried out parts of the experiments to that effect.…”

Airborne Fiber Concentration and Size Distribution of Mineral Fibers in Area with Serpentinite Outcrops in Aichi Prefecture, Japan.

“…On the other hand, the geometric mean of fibrous calcium sulfate concentrations at the quarry property boundary (in operation) was similar to those in other areas. Calcium sulfates have also been frequently found in urban atmospheres 18,21,22) . Fibrous magnesium silicate and aluminum silicate were found in the stone samples, but fibrous calcium sulfate was not found in any bulk samples collected in this study.…”