Field comparison of manual and semi-automatic methods for the measurement of total gaseous mercury in ambient air and assessment of equivalence

• Published in: Journal of environmental monitoring 2012-02, Vol.14 (2), p.657-665
• Main Authors: Brown, Richard J. C, Kumar, Yarshini, Brown, Andrew S, Dexter, Matthew A, Corns, Warren T
• Format: Article
• Language: English
• Subjects: Air Pollutants - analysis; Air Pollution - statistics & numerical data; Atmosphere - chemistry; Automation; Environmental Monitoring - methods; Mercury - analysis
• ISSN: 1464-0325; 1464-0333
• DOI: 10.1039/c2em10719h

The manual and semi-automatic methods for the measurement of total gaseous mercury in ambient air have been compared in a field trial for the first time. The comparison results have shown that whilst the expected random scatter is present, there was no significant systematic bias between the two methods, whose operational differences have also been outlined and analysed in this work. Furthermore it has been observed that because variation in instrument sensitivity is largely random in nature there is little effect on the results of the comparison if the period between instrument calibrations is altered. When the manual and semi-automatic methods are compared according to guidelines produced by the European Commission the results presented here, taken together with other supporting evidence, strongly suggest that the two methods are equivalent. The results of the first field trial to compare the semi-automatic reference method with the manual method for the measurement of total gaseous mercury in air are presented.