EFCOG Best Practice #65
Version with White Paper
Engineering Calculations Best Practices White Paper 2008-12
Point of Contact: Ken Keith,
Brief Description of Best Practice: The purpose of
this paper is to present guidance for developing engineering
calculations to assure that such technical documents meet
the quality requirements of 10 CFR 830 and DOE O 414.1C.
More specifically, this paper presents guidance related to
the following general topics: Development; Design
Input/Assumptions; Documentation/Content; Format; Rigor;
Review/Verification; Approval; Revisions.
Guidance for this paper was also taken from ASME NQA-1,
Quality Assurance Requirements for Nuclear Facility
Applications and its predecessor ANSI N45.2.11,
Quality Assurance Requirements for the Design of Nuclear
Power Plants. These standards clearly
point to what can be described as a graded approach.
This guidance presented in this paper is intended to apply
to safety related structures, systems and components (SSCs)
whose reliable performance prevents or mitigates accidents
that could cause undue risk to the health and safety of the
public. Extension beyond this scope to non-safety related
SSCs represents good engineering practice.
Why the best practice was used: This paper was
developed in response to concern for this topic expressed in
the DOE HS-64 Office of Environment, Safety and Health
Evaluations site assessment reports.
What are the benefits of the best practice:
Implementation of these practices helps ensure that
calculations contributing to safety are complete, concise,
What problems/issues were associated with the best
practice: The paper may appear to require a level of
rigor greater than typical practice; however, these features
are important to ensure the quality necessary to ensure the
calculations are reliable.
How the success of the Best Practice was measured:
Much of the guidance presented in this paper is already
practiced at various DOE sites and as such is a compilation
of the many of the best concepts from across the DOE complex
as compiled by the author and with the concurrence of the
members of the Engineering Practices Working Group (EPWOG).
Description of process experience using the Best
Practice: DOE sites using the concepts in this paper
have benefitted from improved quality of calculation result
and better documentation for future review and understanding
of previous work. Contributes to several ISM Core Functions
and Guiding Principles: Define scope of work; Identify and
analyze hazards; Develop and implement hazard controls; and
Perform work within controls.