ENGINEERING
MANAGERS
FORUM
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REGION
V ENGINEERING MANAGERS FORUM |
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GUIDELINES
FOR THE ESTABLISHMENT
OF DESIGN BASES
DOCUMENTATION PROGRAMS
May 19,1989
GUIDELINES FOR THE ESTABLISHMENT OF
DESIGN BASES DOCUMENTATION PROGRAMS
1.0 PURPOSE
1.1 SCOPE
2.0 EVALUATIONS
3.0 GUIDELINES
4.0 REFERENCES
APPENDICES
B - DEFINITIONS
C - EXAMPLE OF SAFETY SYSTEM DESIGN BASES
GUIDELINES FOR THE ESTABLISHMENT OF
DESIGN BASES DOCUMENTATION PROGRAMS
1.0 GUIDELINE PURPOSE
The purpose of this Guideline is to provide each of the Region V nuclear utilities with strategic information for the development and implementation of Design Bases Documentation Programs. This information has been structured in a guideline format that describes the boundaries for acceptable design bases programs. Implementation of a design bases program within each utility can be accomplished by alternative approaches as specified in Section 3.0. This guideline is intended to provide a consistent methodology within the framework of each utility's internal constraints for Configuration Management.
1.1 GUIDELINE SCOPE
The guidelines discussed in this report are the product of the Configuration Management Working Group chartered by the Region V Nuclear Engineering Manager's Committee.
A set of definitions derived from nuclear industry practices, INPO Guidelines, and Federal codes and standards are included as guidance.
Section 2.0, Evaluations, outlines typical methods for detaining.
Information needed to support design processes.
Acceptable techniques for relating Design Bases information to the information contained in Safety Analysis Reports (50.34 requirements).
Methods for handling open items that may be identified during the preparation of Design Bases Packages.
The heart of this guideline is Section 3.0, "Guidelines", which presents the structured elements that should be included in each utility's Design Bases Program.
Included are:
Program Scope
Definition and Documentation of Program Purpose and Processes
Approach to Documentation
Definition of Users
Program Schedule
Quality Assurance
Verification
Open Items
Relationship Between Licensing Bases and Design Bases Documentation
Use of Pre-Appendix B Design Information
Relationship Between Design Bases and Other Technical Information
Training
Section 4.0 gives a detailed list of all reference documents used in preparation of this guideline.
The Appendices include examples of the types of information required in these programs, definitions, and acceptable alternative methods for program implementation.
2.0 EVALUATIONS
Development of Design Bases Information Design Bases information is a very small subset of the total amount of design
input information that is pertinent to a system, structure, or component. A definition of "design bases" per 10CFR50.2 states a useful distinction
between the larger set of "design inputs" and the information that constitutes
design bases. All information to be included in the design bases should be
rigorously limited to:
specific functions to be performed by a structure, system, or component
and specific values chosen for controlling parameters as reference bounds for
design. Implicit in this definition is documentation of the reason why a function
must be performed and why a specific value or range of values is necessary as a
controlling parameter. Design bases constitute those design inputs that define the systems function
and the "values" for parameters that are derived from accident analysis for the
system or from "state-of-the-art" design practices such as code requirements.
Typical design bases are given in Appendix C. An organized review of the system's functions and controlling parameters will
result in a consistent and complete definition of the design bases, which should
be stated from a regulatory perspective. Relation to Safety Analysis Report Design Bases information should be distinguished from licensing bases
information such as contained in the Safety Analysis Report. Regulatory
documents such as the FSAR, VSAR, and Safety Evaluation Reports contain a
mixture of design bases information and other descriptive or derived
information. These documents may not include all of the functions or values that
are a part of the design bases. However, it is essential that statements made in
these documents are consistent with the design bases.
3.0 GUIDELINES
Guidelines for assembling and documenting information that include the design bases for a system, structure, or component (SSC) are outlined below.
3.1 PROGRAM SCOPE
Design bases programs shall pertain to those SSCs that are important to plant safety and to the generation of electricity. Design basis documentation should be prepared to address systems, structures, components and topical design considerations, that are safety related, can cause challenges to safety systems or are significant to plant availability.
The Design Bases Document should provide the basis for the plant in its current configuration.
3.2 DEFINITION AND DOCUMENTATION OF PROGRAM PURPOSE AND PROCESSES
The basic goals, objectives, and sub-objectives for a design bases program shall be documented and approved by utility management as a necessary part of defining the program scope and direction of their particular utility.
3.3 DEFINITION OF USERS
Design bases programs should be designed to provide controlled user-friendly information to engineering, operations, maintenance, procurement, quality assurance, and plant support groups. These organizations should participate in the determination of scope, level of detail, and the review of the design bases document.
Design bases programs shall be designed and developed to implement the approved goals, objectives, and sub-objectives. These programs shall be documented by appropriate procedures, guides, and standards covering the overall program and all operational elements.
3.4 APPROACH TO DOCUMENTATION
Three basic approaches to documentation of information exist, as outlined below. Note that "design bases" is a subcategory of information in all approaches.
1) Index Approach - includes minimal text with extensive references to other documents. References may include:
system descriptions
component descriptions
calculations
procurement specifications
license/technical specifications
other documents
2) Mixed Approach - includes use of text information plus extensive references. For example, a mixed approach might be structured to include texts of:
system descriptions
component descriptions
design bases
With references to:
calculations
procurement specification requirements
license/technical specifications
other documents, letters, etc.
3) Comprehensive Approach - provides extensive hard copy information such as:
design bases
system descriptions
component information
system functions, safety and non-safety
calculation and calculation summaries
procurement specification requirements
lists of related drawings
related licensee technical specification sections
Minimal cross-referencing of most documents is included.
Any of these approaches are acceptable. No industry consensus has been reached or is necessary. In general, it is unnecessary to duplicate the content of other self-contained documents such as:
ASME Code Stress Reports
Equipment Qualification Data Packages
Vendor Manuals
Procedures for Operations and Maintenance
Actual Industry Codes and Standards
Specifications
3.5 PROGRAM SCHEDULE
Design bases programs should commence with a pilot phase intended to develop the basis program process, initial cost/schedule data, format/scope, and user interfaces and should be scheduled for completion within 5 years beyond the pilot program phase.
3.6 QUALITY ASSURANCE
Information gathered under the auspices of the program shall be assembled, verified, documented, and controlled in accordance with a quality assurance program responsive to the requirements of 10CFR50 Appendix B.
3.7 VERIFICATION
Verification and Validation:
Careful consideration of the verification program is required.
Acceptable approaches include:
1 ) Follow-up internal validation using a process similar to NRC Safety System Function Inspections (SSFls). This alternative approach could be useful to validate a sample of the DBDs produced or as a means of confirming that the program pilot DBDs are adequate.
2) Verification using a design review plan developed from each DBD. Considerations for the sample plan include:
a) Technical staff experience with system
b) Experience from previous SSFI reviews or in-house design reviews processes
c) Assessment of the type and frequency of discrepancies that arose during preparation of the DBD.
Typically, the verification plan should include two elements: (1) an overall review to identify omissions or "holes" and (2) a fact-for-fact check of a portion of the document (perhaps 10%) to verify correct translation of information from the sources. Acceptance criteria for this review shall be provided in the program documentation developed by each utility.
3.8 OPEN ITEMS
Open items identified during development of the design bases document shall be addressed as defined in the individual program plans.
3.9 RELATIONSHIP BETWEEN LICENSING BASES AND DESIGN BASES DOCUMENTATION
Licensing bases documents such as FSAR, USAR, Technical Specifications, commitments, etc., shall not be considered to be design bases documents. Commitments made via the licensing process to adopt specific technical options are not part of the plant design bases until specifically included in the design bases documents or procedures and then become a design input for the final design.
However, in regard to Technical Specifications, it should be noted that the document values agreed upon during the licensing process may be more conservative than the design bases or may be expressed in a different format derived directly from the system design. To assure that modifications will be consistent with the technical specifications and not cause unintended violations, the technical specifications and other licensing documents should be reconciled with the design bases.
3.10 USE OF PRE-APPENDIX B DESIGN INFORMATION
Information developed prior to imposition of Appendix B of 10CFR50 may be used as the authoritative technical basis for design, maintenance, and operation provided that such information:
is legible and has been appropriate labeled,
can be logically followed, and
is pertinent to the current plant configuration.
No supplementary verification is required if the above attributes are present. The program documentation should provide specific utility requirements for use and incorporation of this information.
3.11 RELATIONSHIP BETWEEN DESIGN BASES AND OTHER TECHNICAL INFORMATION
Documents prepared by the utility according to their specified program may contain only design bases information or may contain both design bases information and other technical data. In either case, the document should be organized such that design bases information can be differentiated from non-design bases information or data.
3.12 TRAINING
Design bases training shall be documented in each utilitys specific program.
3.13 FORMULATION OF DESIGN BASES STATEMENTS
Design bases should be stated in broad terms and be focused on the mission or function of the particular safety system. Design bases should be strictly limited to the scope outlined in the definition of 10CFR50.2 and should include regulatory requirements and the technical bases for design which demonstrates compliance to the regulatory requirements.
4.0 REFERENCES
4.1 - 10 CFR 50.34, Contents of applications: technical information
4.2 - 10 CFR 50.59, Changes, tests and experiments
4.3 - INPO 87-006, Reports on Configuration Management in the Nuclear Utility Industry
4.4 - 10 CFR 50.2, Definitions
4.5 - ANSI N45.2.11 - 1974, Quality Assurance Requirements for the Design of Nuclear Power Plants
4.6 - ANSI N45.2.13 - 1976, Quality Assurance Requirements for Control of Procurement of Items and Services for a Nuclear Power Plant
4.7 - ANSI 18.7 - 1976, Quality Assurance Requirements for Operating Nuclear Power Plants
4.8 - Regulatory Guide 1.64, Revision 2, June 1976, Quality Assurance Program Requirements for the Design of Nuclear Power Plants
4.9 - Regulatory Guide 1.74, Revision 0, February 1974, Quality Assurance Terms and Definitions
4.10 - ANSI N45.2.10 - 1973, Quality Assurance Terms and Definitions
4.11 - 10 CFR Part 100, Reactor Site Criteria
4.12 - 10 CFR Part 50, Appendix B, Quality Assurance Criteria for Nuclear Power Plants...
TYPICAL
DESIGNS BASES DOCUMENTS
Include but are not limited to:
Code of Federal Regulations 10CFR 50, Reactor Licensing, including but not limited to the following appendices:
Appendix A - General Design Criteria
Appendix E - Emergency Planning
Appendix I - ALARA Guidelines
Appendix J - Leak Testing
Appendix L - ECCS Evaluation Model
Appendix R - Fire Protection
Code of Federal Regulations 10CFR 73, Physical Protection of Plants and Materials
Code of Federal Regulations 10CFR 100, Reactor Site Criteria
Industry Codes and Standards including but not limited to the following:
ASME
ANSI
ASCE
IEEE
ACI
AISC
HI
AE/NSSS Design Guides and Standards
Design Criteria
Regulatory Guides
Back to Table of Contents
APPENDIX A (continued)
TYPICAL
Include but are not limited to:
Engineering, engineering evaluations, and procurement engineering practices, procedures, and department instructions and their implementing administrative forms that provide for the evaluation, justification, documentation, or implementation of a design change
Computer codes used for design or design analysis (including user manuals)
Design baseline analyses and calculations to establish effects of postulated accidents
Transient analysis
Seismic site-specific criteria
Flooding site-specific criteria
Calculations or analyses that verify that the restraints imposed by the design bases have not been exceeded
Component classification evaluations
Load sequencing and electrical supply sizing calculations
Setpoint calculations and methodologies
Equipment sizing calculations
Motor-operated valve calculations, analyses, or test results that establish limit switch tolerances/settings or torque switch tolerances/settings
Reports and engineering studies that verify that the restraints imposed by the design bases have not been exceeded
Equipment qualification
Stress
Seismic
Environmental
Fire protection safe shutdown capability assessment
Relay protection coordination studies
Safety evaluations and technical review checklists/results
Technical review checklists
10CFR 50.59 checklist
APPENDIX A (continued)
TYPICAL
Include but are not limited to:
System Description Manuals
Specifications
Component
Material
Design
Installation
Procurement
Piping classification list
Valve mark number list
Process software (or firmware) requirement specifications
Vendor engineering documents including:
Technical manuals
Vendor drawings
Information bulletins
Equipment qualification reports (specifically maintenance requirements)
Instrumentation and control setpoint documents
Plant component lists, including but not limited to:
Valves
Equipment
Line
Breakers and other electrical equipment
Instrumentation and controls
Equipment qualification
UFSAR
Drawings
Mechanical
Basic flow diagram
Heat balance
P & ID
Nuclear
Basic flow diagram
P&ID
Radiation
Plant Design
Area Drawings
General
CONFIGURATION MANAGEMENT AND DESIGN BASES
PROGRAM DEFINITIONS
1. Configuration Management: An integrated management process whereby (1) the design requirements for plant structures, systems, components, software, and firmware are defined and documented, (2) changes to these design requirements are identified, documented, controlled, evaluated, and approved or disapproved, and (3) approved design changes and implementation status are recorded and reported throughout the life of the plant, which results in the accurate implementation of design output information (a) into the physical configuration of the plant and (b) into selected plant configuration documents specifying operations, maintenance, testing, installation, procurement, and training requirements.
2. Design Bases: Information that identifies the specific functions to be performed by a structure, system, or component of a facility and the specific values or ranges of values chosen for controlling parameters as reference bounds for design. These values may be (1) restraints derived from generally accepted "state-of-the-art" practices for achieving functional goals or (2) requirements derived from analysis (based on calculations and/or experiments) of the effects of a postulated accident for which a structure, system, or component must meet its functional goals. (10CFR50.2)
3. Design Input: Those criteria, parameters, bases, or other design requirements upon which detailed final design is based. (ANSI N45.2.11 - 1974) See Appendix A for typical document list.
4. Design Process: Documented methods (engineering policies, procedures, practices, and instructions) and the documentation of their use (calculations, engineering studies, evaluations, technical review checklists, safety evaluations, computer codes used for design and associated test cases, etc.) that ensure that applicable design inputs are correctly translated into design output. (ANSI N45.2.11 - 1974) See Appendix A for typical document list.
5. Design Output: Documents such as drawings, specifications, and other documents defining technical requirements of structures, systems, and components. (ANSI N45.2.11 - 1974) See Appendix A for typical document list.
6. Open Items: Those items that are discovered during the performance and evaluation of design bases documents that are discrepant and require correction.
7. Plant Configuration Documents: Documents containing current information that has been effectively translated from design output documents that provide detailed instructions and data used by plant personnel in the conduct of activities related to operations, maintenance, testing, procurement, training, and modification. These documents integrate work practices and design output information such that instructions (and training) are provided for the conduct of the subject activities by personnel in a manner that will preserve the plant design bases. (ANSI N45.2.13 - 1976 Section 3.3.2; ANSI N18.7 - 1976 Sections 5.2.13.1, 5.2.7, 5.2.8, 5.2.9, 5.2.13.2, 5.2.13.3, 5.2.18, 5.2.19, etc.) see Appendix A for typical document list.
8. Design: Technical and management processes that begin with identification of design input and lead to and include issuance of design output documents. (ANSI N45.2.11 - 1974)
9. Final Design: Approved design output documents and approved changes thereto. (ANSI N45.2.11 - 1974)
10. Design Change: Changes to approved design output documents. (Reg. Guide 1.64, C.3; ANSI N45.2.11 - 1974 Section 1.8)
11. Modification: A planned change in plant design or operation accomplished in accordance with the requirements and limitations of applicable codes, standards, specifications, licenses, and predetermined safety restrictions. (ANSI N45.2.10 - 1973)
12. Design Equivalent Change: A design change that is limited to replacement of materials, components, consumables, or spare parts that are similarly procured and are at least equivalent in performance to the item being replaced. Design changes in this category require an evaluation to assure that interfaces, interchangeability, safety, fit, and function are not adversely affected or contrary to applicable regulatory or code requirements. (ANSI N18.7 - 1976)
13. Design Documents: A generic term that includes design bases, design process, and design output documents.
14. Configuration Management Program (CMP) Documents: Information used in the configuration management process including design bases, design process, design output, and plant configuration documents.
15. Operable, Operability: A system, subsystem, train, component, or device is considered to be OPERABLE or have OPERABILITY when it is capable of performing its specified function(s) and when all necessary attendant instrumentation, controls, electrical power, cooling or seal water, lubrication, or other auxiliary equipment are also capable of performing their related support function(s). (Typical technical specifications definition)
16. Key Parameters Values: The actual test values of design bases parameters that directly correlate to capability of the system, component, structure, or topical issue to perform its design bases functions.
17. Margins: The difference between the actual operating point or failure point for a system, component, or structure and the minimum operating, licensing, or theoretical design point of a technical specification.
18. Safety Functions: Those system, structure, or topical issue functions that directly or indirectly support one or more of the following plant nuclear safety performance goals:
1) Maintain reactor coolant pressure boundary integrity.
2) Provide capability to shut the reactor down and maintain the safe shutdown condition.
3) Prevent or mitigate the consequences of accidents that could potentially result in off-site exposures comparable to 10 CFR Part 100 guidelines.
19. Non-safety Functions: Those system, structure, or topical issue functions that support the generation of electrical power and other functions not related to nuclear safety.
20. Design Bases Training Package: A set of documents developed for the purpose of training individuals in design bases areas, including but not limited to the following:
1) Lesson plans
2) Handout materials
3) Examinations
4) Other materials used in training
EXAMPLE OF SAFETY SYSTEM DESIGN BASES
Design Basis for Low-Pressure Core Spray System
Following are the design bases for the low-pressure core spray system, following the design basis definition from 10CFR50.2, which states:
"Design bases" means that information which identifies the specific functions to be performed by a structure, system, or component of a facility, and the specific values or ranges of values chosen for controlling parameters as reference bounds for design. These values may be (1) restraints derived from generally accepted "state of the art" practices for achieving functional goals, or (2) requirements derived from analysis (based on calculation and/or experiments) of the effects of a postulated accident for which a structure, system, or component must meet its functional goals.
LOW-PRESSURE CORE SPRAY SYSTEM FUNCTIONS:
Provide emergency core cooling at low reactor vessel pressures to mitigate the effects of large pipe breaks.
VALUES OF CONTROLLING PARAMETERS USED AS REFERENCE BOUNDS FOR DESIGN
1. Fuel cladding temperatures shall be maintained at or below 2200 degrees F.
2. Total oxidation of the cladding shall be limited to 17% of the original cladding thickness.
3. Hydrogen generation shall be limited to 1% of the amount that would be generated by complete oxidation of all metal in the cladding.
4. A coolable reactor core geometry shall be maintained.
5. The core temperature shall be maintained within acceptable limits during the long-term post-LOCA cooling phase.
6. Parameters used to bound LPCS capability to meet the above criteria:
a) Core thermal power: 105% of rated steam flow
b) Vessel steam dome pressure: l055 psia
c) LPCS system at rated flow
d) Vessel pressure at which LPCS flow starts: 289 psia
e) Assumed pipe break is a double-ended guillotine rupture of one reactor recirculation system suction pipe
ADDITIONAL DESIGN CONSIDERATIONS
1. The LPCS is classified as Seismic Class I and shall be designed to meet the structural requirements imposed by this classification.
2. The LPCS shall be designed so as to maintain the integrity of the reactor vessel and primary containment during and after a design basis event.
3. The LPCS is designated a Quality Class 1 system; its design, fabrication, erection, testing, operation, and maintenance shall be performed according to Quality Class 1 standards.
4. The LPCS shall be designed, operated, and maintained such that it can perform its function continuously in a harsh environment for 4320 hours following a design basis accident.
5. The LPCS shall be designed, operated, and maintained such that the system can perform its function continuously for 4320 hours following an earthquake up to the safe shutdown earthquake (SSE), which may or may not coincide with a design basis accident.
6. The LPCS system shall be designed to ensure its protection from overpressure conditions or to ensure that it can withstand maximum expected overpressure conditions.
7. The LPCS system shall be designed to limit the effects of LPCS pipe breaks on other plant systems, structures, or components.
8. The LPCS system shall be protected from the effects of internally generated missiles.
REGION V UTILITIES
GUIDELINES FOR THE ESTABLISHMENT OF
DESIGN BASES PROGRAMS
MAY 19, 1989
| N/A Warren Peabody Manager, Nuclear Engineering SMUD
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/s/ Ed Sterling Manager, Nuclear Engineering Arizona Public Service
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| /s/ for Gary Moore E & C Manager PG&E
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/s/ Larry Harrold Manager, Nuclear Engineering WPPSS
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| /s/ D. E. Nunn SCE
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/s/ T.D. Walt Portland General Electric
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Distribution:
B. Croley, SMUD
A. Roller, PGE
G. Moore, PG&E
J. Allen,
APS
CM Working Group Members