Derivation of Facility Modes

DOE-STD -3009-94

SSCs or SACs noted in Section 3.3.2.3.2 and their associated assumptions

requiring TSR coverage identified in Section 4.4.X.5, and any other TSR

assumptions.

Provide for significant worker safety. These features are safety-

significant SSCs or SACs identified in Section 3.3.2.3.3 and their

associated assumptions requiring TSR coverage identified in Section

4.4.X.5, and any programs identified as needing coverage in TSR

administrative controls in Section 3.3.2.3.3.

Provide for significant public safety in accordance with implementation of

the Evaluation Guideline. These features are safety-class SSCs or SACs,

and assumptions requiring TSR coverage identified in Sections 3.4.2.X.5,

and 4.3.X.5.

Presentation of the summary of TSRs could easily become disorganized and

difficult to follow. It is recommended that the information be distilled into an

organized presentation (e.g., table format) that identifies the relevant hazard and

the major features relied on for protection against that hazard. This presentation

will form the basis for organization of the remainder of the chapter. Associated

TSR SLs, LCSs, LCOs, surveillance requirements, administrative controls and

Design Features identified throughout the remainder of the chapter need to be

noted in this presentation for overall clarity.

This subsection will specifically note those safety SSCs listed, if any, that will not

be provided with TSR coverage and provide accompanying explanation.

5.4

DERIVATION OF FACILITY M ODES

This section derives basic operational modes (e.g., startup, operation, shutdown)

used by the facility that are relevant to derivation of TSRs. The definition of

modes required in this subsection expands and formalizes the information

provided in Chapter 3, "Hazard and Accident Analyses," regarding operational

conditions associated with accidents.

5.5

TSR DERIVATION

Note: This information can be organized by the hazard protected against, the

specific features or even actual TSRs if desired. The choice of a specific method of

organization is left to the discretion of the DSA preparer. The following format is

repeated sequentially for each TSR ("X").

5.5.X [Applicable Hazard/Feature/TSR "X"]

This subsection identifies the specific feature(s) listed in Section 5.3 and the

relevant modes of operation.

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