Safety Basis

DOE-STD-1073-2003

Configuration Management

of the documentation for the proposed change. If it is determined that the proposed

change could impact an SSC that is part of the configuration management equipment

database, then the proposed change will need to be processed through the change control

process. Furthermore, following review and approval of the proposed change, the

configuration management equipment database will need to be updated as appropriate to

reflect the change.

3.11.2 Safety Basis

Section 3.2 discusses how the Safety SSCs identified in the DSA constitute the baseline

set of SSCs that are to be controlled under the configuration management process. It also

discusses including other SSCs such as those identified as necessary for:

defense-in-depth,

critical mission functions,

environmental protection,

protection of costly equipment or functions,

protection of adjacent SSCs, or

critical software functions

Configuration management should be used to control and document changes to the safety

basis (including the DSA and the Technical Safety Requirements or TSRs). The

relationship of the process of documenting the configuration management design

requirements to the safety basis required by Subpart B of 10 CFR Part 830 for hazard

category 1, 2, and 3 nuclear facilities is illustrated in Figure 3-6.

The relationship of the Unreviewed Safety Question (USQ) process to configuration

management is addressed in the discussion on change control in Chapter 5.

3.11.3 Design Basis versus Design Requirements

The design requirements are the output of the design process as shown in Figure 3-4.

The design basis provides the technical and analytical basis for the design requirements.

The design requirements specify "what" is required and the design basis documents

"why" a design requirement is specified. In addition to safety basis documents (DSAs

and TSRs), design basis information is found in other documents, such as transient

calculations, setpoint calculations, and sizing calculations.

There may be differences between the values in the design bases and the design

requirements for a facility or activity. For example, the design basis may specify a

requirement for a pump to deliver 160 GPM, while the design requirements may specify

a pump rated to deliver a flow of 200 GPM. This difference may represent conservatism

that the design engineer felt was appropriate or the higher rating may have been chosen to

match the rating of an available, off-the-shelf pump.

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