Abstract
Safety assessments and environmental impact statements for facilities require an estimation of airborne releases. Aerosols generated by accidents are being investigated to develop the source terms for these releases. The lower boundary accidental release event would be a free fall spill of powders or liquids in static air. Experiments measured the mass airborne and particle size distribution of these aerosols as a function of source size and spill height. Spill height and source size were significant in releases of both powders and liquids. Releases can be estimated using the relationship of source quantity and spill height. If definitive information is not available, the weight % of source initially airborne from a spill in static air can be estimated as 0.12% for powder and an order of magnitude lower for liquid. Powder median aerodynamic equivalent diameters ranged from 6 to 26.5 µm; liquids 4.1 to 34 m. All of the spills produced a significant fraction of respirable particles 10 µm and less.