Terminology

DOE-STD-1021-93

1.4

Terminology

Throughout this document, the terms "higher" performance category and "lower" performance category are

used. These terms refer to categories with more stringent or less stringent NPH mitigation requirements,

respectively. As defined in the NPH Implementation Guide to DOE Order 420.1, performance categories

range from 0 to 4 in order of increasingly stringent NPH mitigation and performance requirements and with

decreasing values of annual probability of exceedance of acceptable behavior limits.

1.5

Organization of the Document

This standard has been developed and organized as an aid to the engineers and DOE facility managers who

have the responsibility for selecting performance categories of SSCs per the NPH Guide for DOE Order

420.1 (DOE G 420.1-2).

Section 2 provides the criteria for selecting performance categories of SSCs. Section 3 presents

recommended general procedures for systematic application of these criteria. This section also provides

discussions and examples which will enable the user to understand and interpret the criteria correctly and

easily. Section 4 lists the references cited.

1-3