2. The consequence of criticality should be examined for the purpose of establishing whether a
particular control is safety class or safety significant, equipment important to safety, or merely
provides defense in depth;
3. The CSEs that cover the fissionable material operations addressed by the DSA should be
examined to ensure that bounding assumptions or analysis conditions are considered as potential
4. All passive engineered features credited in the CSE should be considered for selection as a DSA
5. All active engineered features credited in the CSE should be considered for selection as a safety
class or safety significant Structures, Systems or Components (SSC) with associated safety limits
or limiting condition of operations as appropriate;
6. Not all engineered features (active or passive) need be selected for inclusion in the DSA/TSR.
The minimum set of controls selected for inclusion should be those that meet the following
conditions: (A) loss of the single control under consideration could directly result in a criticality
accident (such a system would require DOE approval according to 420.1B), (B) loss of the
control could result in a singly contingent condition, and (C) active controls requiring calibration.
Additional engineered features (active or passive) beyond the minimum set may be selected as
7. If all of the credible scenarios are shown to be subcritical by engineered features, then specific
administrative controls (see DOE-STD-1186-2004, Specific Administrative Controls) are not
8. Only administrative controls meeting at least one of the following criteria should be considered
for inclusion: (A) credible violation of the control could directly lead to a criticality accident, (B)
if the safety function were to be equivalent to a safety class or safety significant engineered
control (as discussed in DOE-STD-1186-2004), and (C) general references to control philosophy
(e.g., mass control or spacing control or concentration control as an overall control strategy for
the process without specific quantification of individual limits).