The hourly volatile organic compounds(VOCs) concentrations between 2005 and 2008 at Bulgwang photochemical
assessment monitoring station were investigated to establish a method for quality assurance and quality
control(QA/QC) procedure. Systematic error, erratic error, and random error, which was manifested by outlier and
highly fluctuated data, were checked and removed. About 17.3% of the raw data were excluded according to the
proposed QA/QC procedure. After QA/QC, relative standard deviation for representing 15 species concentrations
decreased from 94.7-548.0% to 63.4-125.8%, implying the QA/QC procedure is proper. For further evaluation about
the adequacy of QA/QC procedure, principal components analysis(PCA) was carried out. When the data after QA/QC
procedure was used for PCA, the extracted principal components were different from the result from the raw data and
could logically explain the major emission sources(gasoline vapor, vehicle exhaust, and solvent usage). The QA/QC
procedure based on the concept of errors is inferred to proper to be applied on VOCs. However, an additional QA/QC
step considering the relationship between species in the atmosphere needs to be further considered.