STUDIES ON THE RADIOACTIVE DUST. I. RELATIVE DUST COLLECTING EFFICIENCIES OF DIFFERENT FILTER PAPERS

Journal Article · Tue Jan 01 04:00:00 EST 1963 · Proc. Japan Conf. Radioisotopes

OSTI ID:4709670

Honda, Y; Harada, T; Shimizu, H; Morishima, H; Kimura, Y; Koca, T; Niwa, T; Nishiwaki, Y

In order to estimate the radioactivity contained in airborne dust accurately, it is necessary to know the dust collecting efficiencies of the filters under different conditions. Although the dust collecting efficiencies may be influenced by the size of the dust, humidity, flow-rate, and various other factors, the relative dust-collecting efficiencies of some filter papers were examined with naturally occurring radioactive dusts. The dust collectors used in this experiment were DS-200 (dust monitor) and DS-8B (dust sampler) of Kobe Kogyo K. K., both fixed filter paper type. The filter papers examined were Staplex No. 41 (U.S.A.), Toyo Filterpaper Co. No. 5A (Japan), and some other filter papers. The radioactivities collected on the filter papers were estimated from the decay rate to daughter products of radon and thoron origin. As an index of the dust collecting efficiency the radioactivity collected on the filter paper at equilibrium state was used. The possible effects of flow rate, size of the dust, self absorption of soft radiation, and decay rate of the radioactivity were also discussed. The results indicated that there was no significant difference in the relative dust collecting efficiencies of the Staplex No. 41 and the Toyo Filterpaper Co. No. 5A. (JAIF)

• Research Organization: Tokyo Inst. of Tech.
• NSA Number: NSA-17-030080
• OSTI ID: 4709670
• Journal Information: Proc. Japan Conf. Radioisotopes, Journal Name: Proc. Japan Conf. Radioisotopes Vol. Vol: 5th, No. 3
• Country of Publication: Country unknown/Code not available
• Language: Japanese

Related Subjects

ABSORPTION
AIR
CONFIGURATION
DECAY
DUSTS
EFFICIENCY
FILTERS
GENERAL AND MISCELLANEOUS
HUMIDITY
PAPER
RADIATIONS
RADIOACTIVITY
RADON
RADON 220
SAMPLING
THORIN