著者

原 登 本間 克典

出版者

社団法人 日本産業衛生学会

雑誌

産業医学 (ISSN:00471879)

巻号頁・発行日

vol.15, no.3, pp.245-249, 1973 (Released:2011-03-04)

参考文献数

7

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Atmospheric concentrations of cyanides in various kinds of plating workshops were determined, and it was cleared that there was an intimate relation between the atmospheric concentration of cyanides and pH of the plating solutions. The more alkaline the solution, the less became the concentration of cyanides. Cyanides contained in the overflowed solution from the plating bath changed to hydrogen cyanide gas while the solution dried up spontaneously, and this gas diffused into the workshop.For sampling cyanides in the air, impinger should be used. The sampling ability of the sampling solution was closely related with its alkalinity. If the aqueous solution of sodium hydroxide is used as the sampling solution, the alkalinity of the solution should be more than 0.2 normal for long time bubbling and more than 0.02 normal for short time bubbling. During the bubbling procedure, the alkalinity of the sampling solution decreased gradually. And the solution should not be used for sampling cyanides if its alkalinity is less than 0.001 normal. If the alkalinity of the sampling solution is exhausted, this solution can not preserve the captured cyanides any more.