The U.S. Environmental Protection Agency (EPA) is in the process of revising the National Ambient Air Quality Standards for total suspended particulates (TSP) to account for the fact that smaller particles are responsible for adverse health effects. The new standard has not been finalized but is expected to be for PM10 particulate matter with aerodynamic diameters of 10 microns or below. The states will be required to revise their State Implementation Plans (SIPs) for attainment or maintenance of the standard. For the States use, EPA is developing and will validate an Urban Particle Model. Philadelphia was chosen as the site for a validation study because it has a good mix of industrial emissions and is the site of an EPA validation program for the Urban Airshed photochemical oxidant model. Ambient data were collected from 6p.m. July 14 to 6p.m. August 13, 1982, at six sites in the Philadelphia area. To assist in the validation program, an emissions input for the urban particle model was obtained. Hourly emissions estimates during the monitoring period for the pollutants fine particles, coarse particles, fine primary sulfate, coarse primary sulfate, and sulfur dioxide are included. All point sources other than 300 major point sources were combined into the 289, 2.5-by 2.5 kilometer grid cells used for area sources and highway vehicles.