Single-failure-proof considerations of the K-25 Site radiation alarm system.

摘要

The Oak Ridge K-25 Site Radiation Alarm System currently provides monitoring coverage for all areas of the plant where nuclear materials are stored or handled. This system monitors these areas with 50 instrument clusters, each comprising 3 independent radiation detection instruments. Cluster placement and radius of coverage provide double cluster coverage for most designated areas of the plant even though the clusters are redundant in themselves; the entire radiation alarm system would be single-failure-proof with inclusion of the modified cluster logic module, printed circuit board in each cluster unit assembly even without redundant coverage. It is estimated that 10 additional clusters, which are not available, will be required to provide full double coverage for all designated plant areas and to provide adequate operating spares for system maintenance activities. The removal of those clusters now providing redundant coverage would easily provide an adequate number of spares and eliminate the need for additional procurement. 2 refs., 3 figs.