Volume 14, No. 1, February 2014, Pages 355-363 PDF(706 KB)
Comparison of NO2 and SO2 Measurements Using Different Passive Samplers in Tropical Environment
Jun He1,3, Honghui Xu2, Rajasekhar Balasubramanian3, Chuen Yu Chan1, Chengjun Wang4
1 Division of Engineering, The University of Nottingham Ningbo China, Ningbo City, Zhejiang Province, China, 315100
2 Zhejiang Meteorological Science Institute, Hangzhou City, Zhejiang Province, 310008, China
3 Department of Civil and Environmental Engineering, National University of Singapore 117576, Singapore
4 College of Chemical and Material Engineering, Wenzhou University, Zhejiang Province, 325035, China
This report describes the results of an inter-comparison study conducted for the sampling and analysis of NO2 and SO2 by using different type of passive samplers in tropical urban environment. For this purpose, field experiments were proposed to be conducted by two round robin tests from Sept. 2007 to Aug. 2008 in Singapore. A set of different types of passive samplers have been exposed to ambient air at atmospheric research station in National University of Singapore along with suitable active samplers (as reference method) for a sufficient period of time (3–4 weeks). Annular denuder system (ADS) active sampling data showed that NO2 concentration level (23.8–28.1 ppb) in Singapore was slightly higher than the WHO guideline but SO2 concentration (12.5–14.9 ppb) was approximately twice the value of WHO guideline. For the two round robin tests, accuracy analysis by using active sampling data as reference demonstrated that grand mean values from passive air sampling (PAS) and active sampler average concentrations, for both NO2 and SO2, are in close agreement with each other. Precision evaluation based on the triplicate samplers co-located at the same sampling site - Singapore showed that most of the passive samplers applied here had repeatability. ANOVA statistical analysis also showed no significant difference between the measurement data obtained by different type of passive samplers for both round robin tests in Singapore.
Inter-comparison study; Passive sampling; Nitrogen dioxide; Sulfur dioxide.