RP 8400 S and 8400 N Ambient Particulate

R&P 8400 S and 8400 N Ambient Particulate Sulfate and Nitrate Monitors: Performance during PMTACS-NY Intensive Field Campaigns and Routine Measurements (Poster Summary) Olga Hogrefe 1, Oliver V. Rattigan, James J. Schwab 1, Frank Drewnick 1, Kevin Rhoads 1, 3, Kenneth L. Demerjian 1 1 -Atmospheric Sciences Research Center, U-Albany, NY; 2 - Division of Air Resources, New York State Department of Environmental Conservation, Albany, NY; 3 – Siena College, Loudonville, NY Prepared for EMEP Workshop on Particulate Matter Measurement & Modeling April 20 -23, 2004, New Orleans, LA

Poster Overview • Introduction: PMTACS-NY intensive sampling campaigns and NYSDEC routine SO 4 and NO 3 measurements; • R&P 8400 N/8400 S design, main features and operational problems; • 8400 S (SO 4) and 8400 N (NO 3) measurements results: time series, diurnal patterns, monthly variations of mass concentrations, comparisons with 24 -hr filters and other semi-continuous instruments, measuring SO 4 and NO 3 • Summary and acknowledgements

8400 S and 8400 N Operational Problems • Short (few days) lifetime Ni. Chrome flash strips; • Decreasing efficiency of molybdenum converter of 8400 N NOx analyzer. • Non-linear aqueous calibration at higher injected amounts of SO 4 (>180 ng) and NO 3 (>60 ng). • Ambient T/RH probe sometimes fails (especially in rainy weather). • Short (1 -2 weeks) life time of Platinum flash strips • High (>0. 5 mg/m 3) and irregular dynamic blanks – QC 2004 • High cost of some spare parts and consumables Most problems associated with 8400 N/8400 S operation were or can be resolved.

Mass Concentration Time Series (Intensive Studies)

Mass Concentration Variations (Routine Measurements) Average Diurnal Patterns (IS 52, Bronx, NY) Monthly Variations of SO 4 and NO 3 Mass Concentrations IS 52, Bronx Wf. M

Comparisons with Other Semi-Continuous Instruments and 24 -hr Filters • Recovery – linear regression slope with intercept set to 0; • Instruments used for comparisons: Aerosol Mass Spectrometer (AMS), Particle-Into-Liquid-Sampler with Ion Chromatographs (PILS-IC), 24 -hr TEOM ACCU filters and 24 -hr STN filters. • 8400 S measurements agree with AMS, PILS-IC and filterbased measurements within 12% or less. • Discrepancy between 8400 N and AMS/PILS-IC is 10 -40%. Compared to filters, 8400 N under-measures nitrate by 3040%.

Questions • What have we (can we) learned about the PM problems from continuous measurements? • What are the advantages of continuous measurements? • Should continuous measurements replace timeintegrated measurements; if so, over what timescale? Are continuous measurements ready for prime time? • How is confidence in the values created in lieu of standards?