Definitions and Acronyms - doe-std-3007-20070005

DOE-STD-3007-2007

DEFINITIONS AND ACROYNMS

DEFINITIONS

CONTINGENCY an unlikely change in a process condition important to the Nuclear Criticality Safety

of a fissionable material operation.

CONTROL an engineered feature (active or passive) or administrative requirement that establishes

constraints on the range of values that process parameters can assume with a given reliability (i.e., failure

frequency) thereby providing a barrier to a criticality accident.

CREDIBLE the attribute of being believable on the basis of commonly acceptable engineering

judgment. Due to the general lack of statistically reliable data, assigning numerical probabilities to

events is not usually justifiable and when used should be backed up with references.

CRITICALITY SAFETY EVALUATION the analysis and documentation that the fissile material

process covered by the scope of the evaluation will be subcritical under both normal and credible

abnormal conditions. The title "criticality safety evaluation" is generic and refers to any document

intended to meet the requirements of ANSI/ANS-8.19-2005, Section 8. Some site-specific synonyms

include, but are not limited to, criticality safety report, criticality safety analysis, and double contingency

analysis.

CRITICALITY SAFETY PROGRAM the Criticality Safety Program required by DOE Order

420.1B.

DOUBLE-CONTINGENCY PRINCIPLE ANSI/ANS-8.1-1998, Section 4.2.2 defines the Double-

Contingency Principle as "Process designs should incorporate sufficient factors of safety to require at

least two unlikely, independent, and concurrent changes in process conditions before a criticality accident

is possible."

PROCESS CONDITION the state of an operation or system involving fissionable material, typically

defined by specifying values or ranges of process parameters.