Round robin tests of arsenic determination by JIS method

Abstract

A joint committee on analysis of mine drainage, organized in the Osaka Mine Safety and Inspection Department, planned a round robin test concerning a spectrophotometric method for the determination of arsenic with silver diethyldithiocarbamate. This is one of the methods prescribed by JIS for the determination of arsenic. Twelve laboratories of mining works participated and in each laboratory two parallel determinations a day were made for three days on the same control sample. The results are summarized as x-R charts for the sample A containing 0.0220 ppm arsenic alone and for the water sample B containing 0.0250 ppm arsenic and various foreign ions. Averages of arsenic found were 0.0222 ppm for the sample A and 0.0255 ppm for the sample B. The results of analysis of variance revealed that the standard deviations among laboratories were 0.14×10-2 ppm for the sample A and 0.06×10-2 ppm for the sample B. © 1978, The Japan Society for Analytical Chemistry. All rights reserved.