Evaluation and Analysis

DOE-NA-STD-3016-2006

operations. Information that supports the documentation used in the preparation of the HAR shall be

complete and accurate in all material respects as required by 10 CFR 830 Subpart B, Appendix E,

Paragraph 2. DOE/NNSA expects a reasonable level of conservatism using engineering judgment

throughout HAR development.

6.1 Evaluation and Analysis

Hazard evaluation characterizes the identified hazards in the context of the actual NEO process. Some

hazards may originate from within the nuclear explosive itself (e.g., internal power supplies, energetic

devices). As discussed in DOE-STD-3009, or superseding directives, the process of hazard evaluation is

qualitative in nature and intended to result in effective controls for prevention or mitigation of

consequences.

The hazard evaluation must be comprehensive in its identification of the physically meaningful hazard

scenarios (i.e., determined to be non-negligible contributors to accident scenario probabilities) and

potential controls. This evaluation is best achieved by initially identifying hazards, controls, and their

safety functions in the hazard analysis process in close association with weapon configurations and

process steps to establish a final control set. This necessitates that the hazard analysis table follow single,

or properly grouped, process steps, weapon configurations, and/or tasks so that controls can be clearly

linked to potential hazards associated with each. This clear linkage between hazard scenarios and

controls also clarifies the important process of safety function definitions.

Hazard scenarios must be fully developed and account for factors that influence scenario progression such

as controls and physical phenomena (e.g., sufficient voltage, capacitance). This evaluation should include

the generation of energy, possible ways to apply the energy to the weapon with consideration of potential

controls, and then the application of energy to a sensitive component that could lead to undesired

consequences. The first two elements of the analysis are developed by the PPC (in consultation with the

Design Agencies (DAs) as appropriate), to define the weapon environment, while the DA weapon

response determines the last element. The definition of the boundary between the hazardous environment

and the weapon response is critical to the proper characterization of the hazard scenarios. The boundary

definition must be well understood by both the PPC and the DA and shall be documented in the HAR.

All hazard scenarios are listed in a hazard table that shall be included in the HAR. Those hazards that are

not screened shall be listed with potential controls in a summary hazard table also included in the HAR.

The following table is a suggested format of a summary hazard table that must be included in the HAR

and present conclusions of the hazard analysis suitable for NEOs.