The results of an extensive investigation of the optical response of thirteen common optical materials to 2.5-MeV electron irradiation is reported. Radiation-induced absorption and absolute radioluminescence yields were measured in the wavelength range 0.14 to 0.9 micrometers for dose rates between 0.05 to 0.00005 rad/sec at doses from 0.0023 to 0.00000045 rads. Sapphire, fused and crystalline quartz and ten Schott optical glasses were investigated. Determinations were made of (a) the absolute radioluminescence yield, (b) the dose rate dependence yield (c) the spectral and temporal distribution of the radioluminescence and induced absorption, (d) the growth curve of the induced absorption versus total dose, (e) the dose-rate dependence of the absorption, and (f) the bleaching of the absorption after irradiation. In addition, where available, samples from different melts were investigated to determine the variation in the above effects with manufacturing variation.