US EPA

2846186 

Journal Article 

Evaluation and calibration of Aeroqual series 500 portable gas sensors for accurate measurement of ambient ozone and nitrogen dioxide 

Lin, C; Gillespie, J; Schuder, MD; Duberstein, W; Beverland, IJ; Heal, MR 

2015 

1 

Atmospheric Environment
ISSN: 1352-2310
EISSN: 1873-2844 

100 

111-116 

English 

10.1016/j.atmosenv.2014.11.002 

WOS:000347266700014 

Low-power, and relatively low-cost, gas sensors have potential to improve understanding of intra-urban air pollution variation by enabling data capture over wider networks than is possible with 'traditional' reference analysers. We evaluated an Aeroqual Ltd. Series 500 semiconducting metal oxide O-3 and an electrochemical NO2 sensor against UK national network reference analysers for more than 2 months at an urban background site in central Edinburgh. Hourly-average Aeroqual O-3 sensor observations were highly correlated (R-2 = 0.91) and of similar magnitude to observations from the UV-absorption reference O-3 analyser. The Aeroqual NO2 sensor observations correlated poorly with the reference chemiluminescence NO2 analyser (R-2 = 0.02), but the deviations between Aeroqual and reference analyser values ([NO2](Aeraq) - [NO2](ref)) were highly significantly correlated with concurrent Aeroqual O-3 sensor observations [O3](Aeroq). This permitted effective linear calibration of the [O3](Aeroq) data, evaluated using 'hold out' subsets of the data (R-2 >= 0.85). These field observations under temperate environmental conditions suggest that the Aeroqual Series 500 NO2 and O-3 monitors have good potential to be useful ambient air monitoring instruments in urban environments provided that the O-3 and NO2 gas sensors are calibrated against reference analysers and deployed in parallel. (C) 2014 The Authors. Published by Elsevier Ltd. 

Semiconductor gas sensor; Electrochemical gas sensor; NO2; O-3; Air pollution exposure