Source Apportionment of One-Hour Semi-Continuous Data Using Positive Matrix Factorization with Total Mass (Nonvolatile plus Semi-Volatile) Measured by the R&P FDMS Monitor

Positive matrix factorization (PMF) was used to elucidate sources of fine particulate material (PM _2.5 ) for a study conducted during July 2003 in Rubidoux, CA. One-h averaged semi-continuous measurements were made with a suite of instruments to provide PM _2.5 mass and chemical composition data. Total PM _2.5 mass concentrations (nonvolatile plus semi-volatile) were measured with a R&P filter dynamic measurement system (FDMS) and a conventional TEOM monitor was used to measure nonvolatile mass concentrations. Semi-volatile material (SVM) was calculated as the FDMS minus the TEOM determined PM _2.5 mass. PM _2.5 chemical species monitors included a R&P 5400 carbon monitor, an Anderson Aethalometer and a R&P 8400N nitrate monitor. Gas phase data including CO, NO ₂ , NO _x , and O ₃ were also collected during the sampling period. Two distinct PMF analysis were performed. In analysis 1, the TEOM was excluded from the analysis and in analysis 2, the SVM was excluded from the analysis. PMF2 was able to identify six factors from the data set and factors corresponding to both primary and secondary sources were identified. Factors were attributed to being primarily from automobile, diesel emissions, secondary nitrate formation, a secondary photochemical associated source, organic emissions and primary emissions. Good agreement was observed between the PMF predicted mass and the FDMS measured mass for both analyses.