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The chemical form of gaseous 35S species produced during the production of H3(32)PO4 was characterized in order to reduce 35S discharge by understanding its production mechanism and chemical reactivity. An air sample was evacuated from the cell in which the H3(32)PO4 production was being carried out and collected in a sample gas reservoir. Gaseous sulfur species contained in the sample were condensed in a cold trap maintained at -180 degrees C and analyzed by means of gas chromatography using a flame photometric detector. Sulfur dioxide (SO2) was the only sulfur species detected. Equilibrium constant calculations showed that SO2 would be expected to be the predominant species produced by reactions of sulfur molecules (Sn:n = 2-8) with oxygen in air and that the quantity of SO2 produced would be reduced by heating the irradiated sulfur target under vacuum or in atmospheres of inert gases.

Five types of ionization chamber survey meters and a type of GM counter survey meter were calibrated for measuring the β-ray absorbed dose rate due to a skin contamination, using natural uranium, 198Au and 204Tl circular sources. To estimate the β-ray absorbed dose rate of a contaminated skin, measurements were done twice by a survey meter without and with a filter, keeping the distance from the contaminated skin surface to the survey meter at 10mm. The absorbed dose rate was obtained by multiplying a net reading (a difference between a reading of survey meter's indicator measured without the filter and a reading measured with the filter) by a multiplying factor.Multiplying factors varied approximately in proportional to the inverse square of source diameter when the source diameter was smaller than the detector's diameter, and approached gradually to a constant value as the value of source diameter increased over the detector's diameter. The multiplying factors of each ionization chamber survey meter were equal to one another within ±30% independently of type (manufacturer) and the maximum energies of sources. The multiplying factors of GM counter survey meter to 204Tl and 198Au sources were three times as large as those to natural uranium sources. The change in the multiplying factor was less than ±20%, when the measuring distance was 10±2mm.

For the estimation of tritium surface contamination by a smear technique, some experiments have been made on the optimum content of glycerol loaded in the smear paper, the fraction of tritium removed by the paper from the surface contamination (i. e., removal efficiency), the counting efficiency for a 2π gas flow counter, and the desorption of tritium from contaminated smear papers.Of the total contamination, 1% and 10% can be removed using a 25w/o glycerol loaded smear paper from a permeable material such as synthetic polymer resin tile and a non-permeable one like stainless steel plate, respectively. The counting efficiency for a tritium smear sample is about 10% for the counter. It is therefore appropriate to assume that the overall counting efficiency in this method (removal efficiency multiplied by counting efficiency) is 0.1% and 1% for the above two materials, respectively. The desorption of tritium is much less from a glycerol loaded smear paper, being only 20% in 40min, while it is as high as 70% from the non-glycerol loaded one.