Optical Characteristics at 3.4 μm Wavelength of Munition-Produced Phosphorus Smoke as a Function of Relative Humidity

Data selected from major U.S. Army field tests conducted during the last four years are analyzed from five different instruments to determine the 3.4–μm wavelength extinction cross-section and mass extinction coefficient of phosphorus smoke. The optical properties of the smokes are found to behave as stochastic spatial and temporal variables with nonstationary means. Data comparisons from different instruments demonstrate a reasonable degree of internal consistency and clearly show the increase of the mass extinction coefficient when the relative humidity is greater than 50%.