Abstract: Failed fuel cladding in light water reactors can lead to premature reactor shutdown for removal of the failed fuel bundles from the core. The lost power and associated fuel replacement costs are astronomically high, approaching a million dollars per day in near term costs. Additionally, the long term affect on an operating plant are the release and distribution around the plant of long-lived fission products which increase radiation levels and impose increased radiological protection procedures. A method has been developed which allows for on-line early detection of failed fuel elements while the plant is operating through flowing off-gas through a conduit to a gamma spectrograph with a time delay to allow interfering short lived isotopes to decay and then analyzing for gamma radiation from at least one of the nuclides Kr-85m, Kr-87, Kr-88, Xe-133, Xe-135, Xe-135m and Xe-138.

Abstract: The disclosed device provides illumination for a radiation dosimeter or other tubular instrument which is held directly in front of the eye for viewing. It can also be used as a compact flashlight for inconspicuous use such as for reading a map in a car or a program in a theater, and it can be carried by medical personnel to illuminate the eye of a patient. The illuminator comprises a light-emitting diode (LED) protruding through an annular spacer. The leads from the LED are bent around a battery comprising one or more button cells. The inner assembly comprising the LED, spacer and battery is held together by a plastic sleeve of shrink-wrap material, such as polyolefin. The inner assembly is enclosed in a thimble-shaped flexible plastic casing, which is adapted to slide onto the end of a dosimeter for permanent mounting. When the user squeezes the casing, the leads are brought into contact with the batteries, thereby completing the circuit, lighting the LED, and illuminating the dosimeter.