Field test data for 42 liter per minute PM2.5 aerosol sampler used during the PMTACS-NY intensives held at Queens College, Queens, NY

A 42 l min−1 (lpm) sampler (Hi-flo) was used to collect 6-h samples during the 2001 summer and the 2004 winter PM2.5 Technology Assessment and Characterization Study-New York (PMTACS-NY) intensives held at Queens College in urban Queens, NY. A sum total of 146 samples collected in 2001 and 113 samples collected in 2004. The samples were water-extracted and analyzed for sulfate by ion chromatography. In addition the 2001 samples had 15 metals determined by inductively coupled plasma mass spectroscopy after water extraction (a soluble fraction) and also after a rigorous microwave digestion (total). The Hi-flo sampler allowed trace metal concentrations to be determined on 6-h samples with nearly the same minimum reporting level (mass loading) as 24-h samplers collected with commercial samplers that operate at 16.7 lpm. We present a comparison of the concentrations of SO4 and 15 selected trace metals measured on the filters collected with Hi-flo and co-located commercial PM2.5 samplers. The Hi-flo sampler is demonstrated to accurately reproduce SO4 and certain elements during the urban intensive. The average slopes of the regressions with a co-located commercial sampler differed from 1 by ±3%. Most aerosol species measured in the 6-h samples collected at Queens College during the 2001 intensive had maximum daily concentrations for the 0600–1200 h sample except sulfate which was maximum for the 1200–1800 h sample and Sb which was uniquely maximum between 0000 and 0600 h. Supporting data suggest afternoon maximum for sulfate is due to more efficient mixing down from aloft the air that was transported from distant sources rather than local photochemistry.