Science Inventory

LABORATORY AND FIELD EVALUATION OF INSTRUMENTATION FOR THE SEMI-CONTINUOUS DETERMINATION OF PARTICULATE NITRATE (AND OTHER WATER-SOLUBLE PARTICULATE COMPOUNDS)

Citation:

Long, R. W. AND W A. McClenny. LABORATORY AND FIELD EVALUATION OF INSTRUMENTATION FOR THE SEMI-CONTINUOUS DETERMINATION OF PARTICULATE NITRATE (AND OTHER WATER-SOLUBLE PARTICULATE COMPOUNDS). Presented at A&WMA 's 97th Annual Conference & Exhibition, Indianapolis, IN, June 22-25, 2004.

Impact/Purpose:

1. Provide the Agency with semi-continuous and real-time instrumentation for its monitoring of ozone, ozone precursors, and reaction products of ozone formation.

2. Provide the Agency with semi-continuous and real-time instrumentation for its monitoring of water-soluble PM components and water-soluble atmospheric gases.

Description:

Studies conducted at the EPA facility in Research Triangle Park, NC and at a field study in Southern California have demonstrated the capability for the semi-continuous determination of particulate nitrate (and other water soluble ionic species). Two instruments, a R&P 8400N particulate nitrate monitor and an ion chromatography (IC)-based prototype monitor developed at Texas Tech University (TTU), were evaluated both in the laboratory using a simulated ambient aerosol and in the field (Rubidoux, CA) during a three week joint ambient comparison study with Brigham Young University (BYU) and the South Coast Air Quality Monitoring District (SCAQMD). During the initial laboratory studies, both instruments were responsive to changes in the simulated aerosol concentration. However, potential problems were discovered involving both instruments during the laboratory based studies and these problems are currently being addressed. Both instruments were then transported to the SCAQMD Rubidoux field site and operated for a period of three weeks (July 1- 21, 2003). Due to manufacturer's quality assurance issues associated with IC components of the TTU prototype instrument, limited data were obtained from this instrument during the three week sampling period. Initial comparisons show general agreement between the R&P and IC-based prototype instruments for the semi-continuous determination of ambient particulate nitrate at lower nitrate concentrations (<15 ug/m3) and an under determination by the R&P instrument at higher concentrations (>15 ug/m3). During the three week study period, 15-minute average particulate nitrate concentrations approaching 30 ug/m3 were observed. Semi-continuous results obtained from the EPA-operated instruments were averaged and compared to integrated sampler results obtained by BYU and SCAQMD. Results of the laboratory and field studies will be addressed.

This paper has been reviewed in accordance with the United States Environmental Protection Agency's peer and administrative policies and approved for presentation and publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.

Record Details:

Record Type:DOCUMENT( PRESENTATION/ PAPER)
Product Published Date:06/23/2004
Record Last Revised:06/21/2006
Record ID: 81134