Evaluation of High-Volume Air Samplers for Ambient Air Quality Monitoring in Real Atmosphere

摘要

Quality Assurance/Quality Control techniques have been studied in order to establish an appropriate level of quality control (QC) during ambient air quality monitoring in real atmosphere. QA/QC study of four high-volume air samplers was carried out at the roof of an ambient air quality site during the Environmental Impact Assessment study. Suspended Particulate Matter (SPM), Sulphur dioxide (S02), Oxides of Nitrogen (NO*) was continuously monitored for 24 hours for 8 days. The average SPM, S02 and NO_x measured by an identical pair of samplers ranged between 79.98 to 82.62 μg/m3; 30.40 to 36.75 μg/m~3 and 31.63 to 36.36 μg/m~3. The standard deviation and coefficient of variation for SPM, SO2 and NO_x were between 13.59-16.69; 8.34-10.14; 7.81-10.01 and 16.45-20.66; 22.71-33.35; 24.68-30.80 respectively. The day-to-day variation and sampler-to-sampler variation was also studied and control chart was prepared for accuracy and precision of the measurements. The QA/QC data generated in the field will be used to monitor reproducibility (precision) of the sampling methods and the accuracy of measurement. Proper quality assurance and quality control (QA/QC) procedures helps in achieving reproducible and reliable results during the ambient air quality monitoring. The reproducibility of the samplers for all the parameters is found to be satisfactory.