Safety Software Quality Assurance - Central Registry

A significant improvement to the safety software at the Department of Energy (DOE) nuclear facilities was achieved with the development and maintenance of a collection, or "toolbox, "of high-use safety software codes. The toolbox codes are compliant with the DOE Safety Software Quality Assurance (SSQA) requirements of DOE O 414.1C and its guidance, DOE G 414.1-4. The toolbox codes are routinely used by DOE to perform calculations and develop data used to establish the safety basis for DOE facilities and their operation, and to support the variety of safety analyses and safety evaluations developed for these facilities. The collection of toolbox codes is referred to as the DOE Safety Software Central Registry.

The Central Registry currently contains software versions for 7 toolbox codes ALOHA, CFAST, EPICODE, GENII, IMBA, MACCS2, and MELCOR. An additional code, Hotspot, is in the process of implementing recommendations for inclusion into the Central Registry. Prior to inclusion into the Central Registry an evaluation, referred to as a gap analysis, of each code is conducted to identify any "gaps" between the SQA practices and DOE's requirements and criteria for safety software. Code-specific guidance reports were also developed to identify applicable regimes in accident analysis, default inputs, and special conditions for using the toolbox codes for DOE applications. These documents as well as general information are available through the links provided above.

While DOE has established the Central Registry and includes codes into this virtual registry, most were developed outside of DOE (e.g., in the private sector or other Federal agencies). Access to the toolbox codes or their use is subject to agreements, conditions and restrictions established by the code owners or Federal agencies.

The Chief Health, Safety and Security Officer (HS-1) is responsible for managing the Safety Software Central Registry. However, the toolbox code owners are responsible for ensuring that the codes are maintained in accordance with established requirements. DOE works closely with the code owners to ensure that adequate technical support and training are available.

Although use of the Central Registry toolbox codes is not mandatory, using the codes offer a number of advantages to the DOE and its contractors. These advantages include: 1) the gap analysis evaluation performed provides valuable information as to the quality of the code, 2) the evaluation extends beyond the DOE SSQA criteria to review the code's capability to properly perform safety basis calculations, 3) DOE-specific guidance document that identifies limitations and vulnerabilities not readily found in other code documentation is available, 4) assessments by the field federal and contractor of the toolbox code may be reduced in scope, and 5) continual monitoring and communication to DOE users of new code features and resolutions to defects important to DOE.

DOE also conducted a survey of design codes currently in use across DOE to determine if any should be included in the Safety Software Central Registry. No additional codes were identified for inclusion. A two-volume report (Volume 1; Volume 2) describes the process and identifies the codes evaluated.

For more information on the Central Registry contact Subir Sen.