ANSI/ANS-8.7-1998;R2007 (R = Reaffirmed): Guide for Nuclear Criticality Safety in the Storage of Fissile Materials

"R" in the numeric designation signifies that the 1998 standard was reaffirmed (recertified) as an American National Standard in 2007.  No changes can be made to a standard during reaffirmation.

This standard is applicable to the storage of fissile materials.  Mass and spacing limits are tabulated for uranium containing greater than 30 wt-% 235U, for 233U, and for plutonium, as metals and oxides.  Criteria for the range of application of these limits are provided.