Additional Considerations cont'd

DOE-STD -3009-94

Appendix A

comprehensive hazard analysis. Generally, the availability of typical preventive or

mitigative features, such as the ventilation and filtration system, given the occurrence of a

DBA in DOE's non-reactor nuclear facilities will reduce potential public doses to well

within a small fraction of the EG. Thus, an approach that also uses frequency of release,

even if equally practical, would not generally result in different SSC classifications.

Moreover, requiring frequency-based calculations would result in enlarging the paper

process, thus undermining DOE's emphasis on comprehensive hazard analysis, without

significant payback in safety assurance on the operating floor.

The protection of the public and workers during normal operations is governed by 10 CFR

835, Occupational Radiation Protection; unintended releases of sufficiently high frequency

as considered a part of normal operations would also be governed by this regulation. This

is not to imply, however, that safety SSCs should be identified based on compliance with

10 CFR 835. It is inherent in the hazard analysis process described in this standard that a

comprehensive spectrum of accidents, including those that may have a higher likelihood,

be identified, evaluated, and analyzed. Any accidents that have a significant consequence

potential to the public or workers, independent of likelihood, must be thoroughly

evaluated, including the identification of any appropriate safety SSCs or administrative

controls.

Toxicological EGs are not specified. There is no industrial or regulatory precedent for SC

designation of SSCs in facilities or processes with only toxicological hazards. SS

designations, which are based on qualitative guidelines, can be triggered without

distinction from both radiological and toxicological hazards. However, controls for

toxicological releases, which trigger nuc lear accidents or have nuclear impacts, are

potential candidates for SC designation.

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