Archon Engineering, PC

Commercial Grade Dedication

To use software for nuclear safety related analysis, the software must be either purchased from a 10CFR50 Appendix B supplier, or it must be commercially dedicated. Commercial software to be used for safety related applications is considered a basic component, and as such must undergo a Commercial Grade Dedication (CGD).
ASME NQA-1 provides guidance on verifying software for safety related use. EPRI Report 1025243 provides guidance on performing a CGD for software and Archon's V&V package becomes an integral part of the end user's CDG process.

A typical CGD package may include the following steps:

  • Identify Application/End Uses
  • Perform Safety classifications (i.e. identify functions, Failure Modes and Effects)
  • Identify Critical Characteristics
  • Select Acceptance Methods and Criteria

As this relates to software, the end user must determine first if the software is to be used in safety related applications, perform a Failure Modes and Effects Analysis (FMEA) to establish consequences of a failure of the software to perform its function, and establish the safety functions of the computer code (e.g. Fathom's function would be to provide process flow analysis, flow rates, pressures, etc.).

Critical Characteristics for acceptance would be the part of the CGD process where important characteristics of the software, that once verified, will provide reasonable assurance the computer software will perform its intended safety function.

The Acceptance Method and Criteria would then be employed to verify the critical characteristics. The V&V package that Archon provides would satisfy much of the acceptance method and criteria requirements of the CGD plan and help to develop the identification of the critical characteristics.
As it relates to AFT's software, this portion of the plan may look like the following:

1. Procure the software from AFT via a commercial Purchase Order
2. Procure the V&V package from Archon via safety related Purchase Order
3. Verify software received from AFT matches the file version, size and date verified by Archon. Each Verification package will identify the Program and database files by File Name, File Version, File Date and File Size. By comparing the files procured from AFT in step 1 above to those files listed in the V&V packaged, the end user is assured that the file version verified by the V&V package is identical to the version procured commercially.
4. Load the software onto the computers that will run the software
5. Run the sample models provided in the V&V package on the end user's machine.
6. Compare results of the sample models of step 5 above to the results included in the V&V package. The V&V package will include a few sample problems with output obtained by Archon in the verification process.

This 6 step plan provides the following assurances

  • The software provided by AFT is identical to the software verified by Archon (verified in step 3 above as well as in step 6 above).
  • The software provided by AFT is demonstrated to produce proper and expected results (as documented in the V&V package provided by Archon).
  • The software runs performed in step 5 and 6 verify that the end user's machine and operating system produce proper and expected results.

The package provided by Archon verifies the proper operation of the software package with its numerous features and options. The in-situ test by the end user does not have to perform this check since Archon has already verified this portion of the CGD plan. The end user must verify that his machine and operating system operate as expected and thus only a few sample problems are necessary for this purpose. The In-situ test also helps provide (in conjunction with step 3) the assurance that the commercial software purchased is identical to the software verified.