Round robin analysis of aluminium using glow discharge mass spectrometry
Abstract
A comparative study between ten European GDMS laboratories was performed using a high-purity 4N (99.99%) Al sample. An analytical procedure including six consecutive analyses for 43 elements was suggested. The concentration levels for the trace and ultratrace determinations ranged from several tens of µg g–1 to low ng g–1 levels. For more than 50% of the GDMS determinations, the repeatability standard deviation within laboratories was less than 10% RSD. Results with confidence intervals for 31 elements are presented for comparison. For the 31 elements, a statistical treatment according to ISO 5725 was performed calculating outliers, mean value, reproducibility, standard deviation between laboratories, and confidence interval (95% significance level) as well as bias from reference values. For 23 elements, no significant bias between GDMS results and accepted reference values could be detected.