[en] An investigation was made of the effects of high-energy radiation and strong acids on the thermal stability of ion exchange resins. Dowex 1-X4 (anion exchange resin) and Dowex 50-X8 (cation exchange resin) were subjected to gamma and alpha radiation in addition to nitric and hydrochloric acids. The resins then were analyzed by differential thermal analysis and infrared analysis to examine the changes in thermal stability. Gamma irradiation (up to 1.6 x 10⁹ rads) did not affect the thermal stability of Dowex 50-X8 in hydrochloric or nitric acid. Gamma irradiation (about 10⁸ rads) of Dowex 1-X4 in nitric acid lowers the exotherm temperature approximately 50 degrees Celsius. The effect of alpha radiation on Dowex 1-X4 is about the same as that of gamma radiation, whereas alpha particles are more damaging than gamma rays to Dowex 50-X8. Contacting the unirradiated resins with hydrochloric or nitric acid did not cause degradation, but both resins reacted with nitric acid at elevated temperatures, which created a thermal instability