This report presents the results of the third inter-laboratory comparison for BTEX automatic analysers performed at the JRC on the 12-15 November 2013. Nine national reference laboratories with a total of eleven instruments, participated in this exercise. Six concentration levels were tested during the inter-laboratory comparison. Benzene concentrations ranged from 1 to 50 µg/m3. The exercise was evaluated according to ISO 13528 methodologies for the evaluation of inter-laboratory proficiency assessment and the recommendation of the protocol N37 of the AQUILA network. Participating laboratories are identified as requested by the AQUILA protocol. The report compares reference and robust average values for the three up and down concentration series tested during the exercise, gives information on the technique and instrumentation used by each participant and shows the linearity test, identification of outliers, repeatability, reproducibility and robustness of the methodology, as well as parameters to evaluate laboratory results: repeatability score, bias and En values. In spite of an unforeseen power failure occurred during the comparison, which lead to a shutdown of all instruments and gas generation for three hours, the comparison exercise could be resumed successfully. The results show a substantial improvement with respect to the previous two inter-laboratory exercise with robust values for the benzene measurements that were in line with average reproducibility values of 7.8 %.

PEREZ BALLESTA Pascual;  CONNOLLY Richard;  DUANE Matthew;  LAGLER Friedrich; 

2015-01-20

Publications Office of the European Union

JRC93075

978-92-79-44687-0,   

1831-9424,   

EUR 27012,    OP LB-NA-27012-EN-N,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC93075,   

10.2788/05280,