The Bouguer-Lambert-Beer law (BLBL), commonly used to describe the extinction of radiation in disperse systems, is known to be valid in the limit of low concentrations only. In Part [1] it was shown that steric particle-particle interactions lead to important effects in the range of high particle concentrations, and two versions of a more general extinction equation including steric interactions were derived fdr the regimes of Fraunhofer diffraction and geometric ray propagation. In this part, experimental evidence for the effects of steric interactions on the extinction of radiation in suspensions of monodisperse spherical particles is given. Various experiments on light extinction and on ultrasonic extinction are combined to cover a broad range of particle size parameters, mechanisms of particle-wave interaction and receiver apertures.