Nuclear safety criteria for special test loads -- N-Reactor

The initial fuel landing for the N-Reactor and the use of a specific alternative fuel element are described in a previous report. It is highly probable that it will also be desirable in the future to irradiate still other types of fuel elements in the reactor. If the test is of small scale, fever than five channels, or if these elements vary only slightly from the initial fuel load (or any other fuel type approved for large-scale use at some future date), the irradiation will be accomplished within the normal administrative procedures and controls established for the Production Testing Program. In this context, in-reactor testing of minor changes in the fuel cladding alloy, alternate methods of affixing end closures, different fuel support designs or similar changes are considered to be within the scope of normal productiontesting. It is possible, however, that it will be desirable to irradiate test fuel elements which are significantly different from any element approved for general use and in quantities of greater than five fuel columns at a given time. A more formalized review of such tests including approval by the AEC would appear appropriate in these instances. The purpose of this document is to outlinemore » criteria which can be usedto judge the stability of all such tests from the standpoint of reactor nuclear safety. It is intended that these criteria apply to test fuel loadings comprising up to 50 fuel columns within the reactor at a given time.« less