Plume opacity and particulate mass concentration

Abstract

A general theoretical relationship between plume opacity and the properties of particulate air pollutants has been developed. These results are in agreement with previously reported theoretical equations for specific emissions and with the known measurements of plume opacity and particle properties. A parameter K, defined as the specific particulate volume/light extinction coefficient ratio (cm3 m-3m), was used to relate the plume opacity to the particle properties. Graphs of K vs. the particle geometric mass mean radius at geometric standard deviations of 1,1.5, 2, 3,4 and 5 are presented for particles of refractive index 1.33 (water) and 1.95-0.661 (carbon). An example is included illustrating the use of the theoretical results to calculate the maximum allowable particle concentration which will meet a given Ringelmann number. © 1969.