An interlaboratory comparison of INAA analytical method for coal fly ash elemental characterization

Abstract

Quality assurance of analytical results has become the high market demand in this globalization era. Accurate and reliable for analytical data is one of the requirements for a testing laboratory to get recognition from customers and institutions that issue certificates, which may be obtained by ensuring the validity of the used analytical methods. Validation of methods applied by laboratories can be done; one of by conducting proficiency tests or inter-laboratory comparative tests. We have been conducted the Inter-laboratory comparative tests for Neutron Activation Analysis for elemental characterization of coal fly ash. Coal fly ash samples were prepared according to ISO Guide 34 and 35, and distributed to eleven NAA laboratories in Indonesia as well as in other countries. As much as 18 elements should be analyzed by participant laboratories. The results were processed statistically using Z-score where it found that three elements (Hg, Se, and Mg) cannot be evaluated due to insufficient data and also high variations of the data, while for other elements such as As, Th, Na, and Sb showed a good agreement among participant laboratories. Through this inter-laboratory comparative testing program, it is expected that NAA laboratories, especially in BATAN, can maintain and improve their performance and quality of their analytical results.