Guiding Principles - doe-std-3009-94_cn3

DOE-STD -3009-94

Guiding Principles

This Standard incorporates and integrates many different approaches regarding DSA

format and content. To ensure a consistent application of this Standard among users, the

following guiding principles are provided.

The focus of this Standard is primarily on Hazard Category 2 and Hazard

Category 3 facilities.

Hazard analysis and accident analysis are merged into one chapter (Chapter 3)

to ensure that the proper emphasis is placed on identificatio n and analysis of

hazards. The hazard analysis distinguishes when accident analysis is required

as a function of potential offsite consequence. Guidance for hazard and

accident analysis is not based on probabilistic risk assessment (PRA).

Defense in depth, worker safety, and environmental issues are identified

Defense in depth as discussed in this Standard, consists of two components:

Equipment and administrative features providing preventive or mitigative

functions so that multiple features are relied o n for prevention or

mitigation to a degree proportional to the hazard potential.

Integrated safety management programs that control and discipline

operation.

Guidance is provided for evaluating the safety of a facility for which

documentable, deterministic design basis accidents (DBAs) do not exist in

order to establish bounding accidents (derivative design basis accidents) that

envelope the safety of existing facilities. Guidance is also provided on the

treatment of beyond design basis accidents.

Distinction is made between "safety-class (SC) structures, systems, and

components (SSCs)," and "safety-significant (SS) structures, systems, and

components," and the balance of facility structures, systems, and components.

Safety-class structures, systems, and components are related to public

protection and are defined by comparison with the numerical Evaluation

Guideline (EG). (See Appendix A of this Standard for additional guidance.)

Safety-significant structures, systems, and components are identified for

specific aspects of defense in depth and worker safety as determined by the

hazard analysis. Specific definitions are provided for these two terms.

Guidance is provided identifying Administrative Controls that are major

contributors to defense in depth, whic h are designated as Specific

Administrative Controls (SAC). This Standard, along with DOE-STD-1186

Specific Administrative Controls, provides guidance applicable to these types

of controls. SACs provide preventive and/or mitigative functions for specific

potential accident scenarios, which also have safety importance equivalent to

engineered controls that would be classified as safety-class or safety-

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