Introduction cont'd - s1073pt10035

DOESTD107393

These various considerations fall naturally into two types, as depicted below. The first type involves

relative importance; one item can be identified as more important than another and therefore can be

assigned a higher priority. The second type involves more situational or circumstantial considerations,

independent of relative importance.

Situational/Circumstantial Considerations

Relative Importance Factors

Facility grade

Facility type and technical characteristics

SSC grades

Facility desired/remaining lifetime

Facility operational status

Programmatic and technical issues

Existing programs and procedures

Facility life-cycle phase

Phased implementation

Other DOE documents present various aspects of a graded approach. For example, DOE 5480.23,

Nuclear Safety Analysis Reports, defines hazard categories for nuclear facilities and specifies

requirements for facilities in those categories. DOE-STD-1027-92, Hazard Categorization and Accident

Analysis Techniques for Compliance with DOE Order 5480.23, Nuclear Safety Analysis Reports,

presents a method for determining the hazard categorizations for nuclear facilities. DOE 6430.1A,

General Design Criteria, presents design criteria for various types of facilities and systems within

facilities, defines and explains safety class items, and specifies design criteria for such items. Similarly,

DOE 5480.30, Nuclear Reactor General Design Criteria, presents criteria for the safety design of

nuclear reactors (criteria for the safety design of nonreactor nuclear facilities are under development).

DOE 5481.1B, Safety Analysis and Review Systems, defines high-hazard, moderate-hazard, and low--

hazard classes of items from an environmental protection perspective. DOE 5480.28, Natural

Phenomena Hazards Mitigation for Department of Energy-owned Facilities, defines performance goals

for maintaining the integrity of SSCs against natural phenomena as necessary to confine nuclear and

other hazardous materials and to protect personnel. DOE 5000.3B, Occurrence Reporting and

Processing of Operations Information, defines Class A and B equipment and defines conditions that

constitute a significant impact on the cost and schedule for completing the programmatic mission of a

facility.

The graded approach described in this Standard is not another layer added to this collection of grading

systems; rather, it is offered as a possible integration of several grading methods into a single method.

The main purpose of a graded approach is to determine the appropriate level of resources that should

be applied when implementing a program. The goal is to apply the highest level of resources to the

most important equipment in the most important facilities and to avoid such expenditures where they

are not warranted. For a highly hazardous facility such as a large nuclear reactor, which could

potentially have serious off-site personnel safety consequences, a significant investment of resources is

appropriate for the systems that prevent, detect, or mitigate such consequences. At the other extreme,

for a low-hazard facility--a hot cell facility, for example--where the greatest hazard is localized (that is,

offsite personnel and workers at other facilities on the site are unaffected), the same high level of

investment would not be appropriate. The grading system should take into account both facility grades

and SSC grades in determining the appropriate level of resources to be applied, and to this end, a

composite grading system could be employed.

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