Measurements of Ground-Level PM2.5 Concentrations Downwind From Southern Prescribed Burns

A comprehensive smoke project, now ongoing for four years, is designed in part to document ground-level PM2.5 concentrations from Southern prescribed burns. Management goals are to find ways to increase the number of burn days and/or the number of acres burned on a given day while remaining within air quality guidelines. Project scientific goals are to advance knowledge on how firing technique influences ground-level smoke concentrations at distances up to 5 miles (8 km) from burn locations. We present the kinds of equipment used to get hourly and daily estimates of PM2.5, the layout of smoke sampling networks set up downwind from burns, and measured ground-level smoke concentrations for 21 prescribed burns. The results to date show no relationship between acres burned and smoke mass measured. Furthermore, daily smoke concentrations measured downwind from the burns are found to be less than that calculated from the VSMOKE model by at least a factor of five.