Quick and simple comparative tests were conducted to evaluate the loss of ductility of irradiated in-pile stainless-steel pressure tubes. Representative conditions of pressure cycling and geometry were used to determine the bursting pressure and fatigue life of both unirradiated control specimens and sections of an irradiated in-pile tube. Irradiation increases the tensile strength and the low-cycle fatigue life of these stainless-steel tubes when subjected to pressure cycling.