Performance evaluation of two commercial chemiluminescence NO_xanalysers according to European Standard EN 14211

Abstract

According to Directive 2008/50/EC, all equipment used for NO(x) fixed measurements must comply with the reference method or equivalent by 11 June 2013. Up to that date, non-type-approved equipment can continue to be used in air monitoring networks and will probably also be used in air pollution studies even after that date. In this context, it is advisable to know how these "old" measuring instruments respond to the requirements of European Standard EN 14211: 2005: Ambient Air Quality--Standard method for the measurement of the concentration of nitrogen dioxide and nitrogen monoxide by chemiluminescence. In this work, we carry out a thorough performance evaluation of two commercial NO(x) analysers, both purchased before 2010, according to the mentioned Standard. Results show that water vapour interference is one of the most important disconformities with this Standard. The expanded uncertainty estimation of both analysers was below the quality objective of the above-mentioned Directive (15%); however, this calculation was performed by applying some modifications to the proposed model of Standard EN 14211. These modifications are also discussed in the paper.

New Methodology to Evaluate and Optimize Indoor Ventilation Based on Rapid Response Sensors

“…Flow 2.0 can measure, every minute, the air quality indices (AQI) and the air concentration levels of different pollutants: nitrogen dioxide (NO 2 ) and volatile organic compounds (VOCs) in ppb v / v , as well as particulate matter equal to or less than 10 and 2.5 microns (PM 10 and PM 2.5 , respectively) in . Although the manufacturer guarantees the precision and reproducibility of the sensor measurements [ 35 ], the portable gauges were validated in the laboratory in a dynamic reference chamber which generated controlled atmospheres [ 36 , 37 , 38 , 39 ]. The measurements provided by the Flow 2.0 were controlled by measurements taken with the continuous analysers Thermo model 42i for NO–NO 2 –NO x , 48i for CO, 49i for O 3 , and 450i for SO 2 –H 2 S, and Syntech Spectras GC955 gas chromatograph for other chemicals.…”

Uncertainty models and influence of the calibration span on ambient air measurements of NO2 by chemiluminescence

“…Further details on these changes are discussed by Doval Miñarro and González Ferradás. 8 3 Results and discussion…”

“…Estimated parameters of eqn(8) together with their standard errors and the residual sum of squares (RSS)…”

Influence of environmental humidity on measurements of benzene in ambient air by transportable GC-PID

“…FID were proved to be affected as well (LeBouf et al, 2013); however, these tests were performed at ppm levels. Among the reference measurement techniques to measure air pollutants, chemiluminescence with ozone to measure NO and NO2 is also humidity-dependent (Gerboles et al, 2003;Hayden, 2003;Miñarro and Ferradás, 2012;Steinbacher et al, 2007); and also UV photometry to measure ozone (Wilson and Birks, 2006). Recently, Bluhme et al (Bluhme et al, 2016) have shown that measurements of SH2 by UV fluorescence are also affected.…”