Techniques for accelerated ionizing radiation testing utilizing electrons from a Van de Graaff generator are described and applied to lithium niobate. A broad optical absorption band of small optical density (<0.1/mm) developed from the middle of the visible to the ultraviolet cutoff. Small dilatations (∼10−5) occurred; in some specimens positive, in others negative. Small changes were seen in the electroacoustical properties: −7% in electromechanical coupling coefficient, −6% in electrical permittivity, and a slight decrease in mode purity. These changes annealed partially at room temperature over a period of several weeks. Further annealing occurred on heating for 15-min intervals at 100 and 140°C; annealing was completed after a heating at 180°C. These effects may be associated with storage of charge in a piezoelectric material. A crystal plate was operated effectively as a piezoelectric acoustical sensor during electron bombardment even at a dose rate 105 R/sec but showed a small decrease in signal-to-noise ratio. The duration of these irradiations shows that no significant radiation damage caused by ionization will accumulate in a century of immersion in coolant sodium in a fast breeder reactor. The lithium niobate is extremely stable toward radiation, behaving like the close packed oxides (e.g., sapphire) rather than as a salt.