Air quality measurements from the Fresno Supersite

The Fresno Supersite intends to 1) evaluate non-routine monitoring methods, establishing their comparability with existing methods and their applicabi lity to air quality planning, exposure assessment, and health effects studi es; 2) provide a better understanding of aerosol characteristics, behavior, and sources to assist regulatory agencies in developing standards and stra tegies that protect public health; and 3) support studies that evaluate rel ationships between aerosol properties, co-factors, and observed health end- points. Supersite observables include in-situ, continuous, short-duration m easurements of 1) PM2.5 PM10, and coarse (PM10 minus PM2.5) mass; 2) PM2.5 SO4-2, NO3-, carbon, light absorption, and light extinction; 3) numbers of particles in discrete size bins ranging from 0.01 to similar to 10 mu m; 4) criteria pollutant gases (O-3, CO, NOx); 5) reactive gases (NO2, NOy, HNO3 , peroxyacetyl nitrate [PAN], NH3); and 6) single particle characterization by time-of-flight mass spectrometry. Field sampling and laboratory analysi s are applied for gaseous and particulate organic compounds (light hydrocar bons, heavy hydrocarbons, carbonyls, polycyclic aromatic hydrocarbons [PAH] , and other semi-volatiles), and PM2.5 mass, elements, ions, and carbon. Ob servables common to other Supersites are 1) daily PM2.5 24-hr average mass with Federal Reference Method (FRM) samplers; 2) continuous hourly and 5-mi n average PM2.5 and PM10 mass with beta attenuation monitors (BAM) and tape red element oscillating microbalances (TEOM); 3) PM2.5 chemical speciation with a U.S. Environmental Protection Agency (EPA) speciation monitor and pr otocol; 4) coarse particle mass by dichotomous sampler and difference betwe en PM,, and PM2.5 BAM, and TEOM measurements; 5) coarse particle chemical c omposition; and 6) high sensitivity and time resolution scalar and vector w ind speed, wind direction, temperature, relative humidity, barometric press ure, and solar radiation. The Fresno Supersite is coordinated with health a nd toxicological studies that will use these data in establishing relations hips with asthma, other respiratory disease, and cardiovascular changes in human and animal subjects.