Document: NUREG-0800
Document ID: 117c3e07-68b8-4bd8-b2f6-f2bcf4de73b9
Document Type: srp
Title: Draft Revision 6 – August 2015
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159A982.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
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observed when reviewing systems specified or designed using such languages. Many vendors of PLCs allow programming languages other than ladder-logic to be used (e.g., C). The reviewer should take this possibility into account and assess the impact of using programming languages on the design of the PLC and the application. An I&C system built using PLCs contains a number of purchased components: hardware, including the processor, memory, I/O equipment, communications equipment, terminals, etc., and software, consisting of one or more operating systems, interpreters, compilers, libraries, configuration software, tools, and variations thereof. This purchased equipment should be of a quality appropriate to the proposed application. BTP 7-18-4 Draft Revision 6 – August 2015 Other issues associated with the application of digital computers to I&C systems, such as maintenance, verification and validation, electromagnetic interference, and calibration, apply and should be reviewed. The staff should not accept an argument that the PLC is somehow simpler or different from a computer and hence does not require the rigorous review that a computer system would receive. 2. Information to be Reviewed Information to be reviewed is contained in the safety analysis report (SAR), revisions to the SAR, license amendment requests, topical reports, or other applicant or licensee documentation. Inspections, tests, analyses, and acceptance criteria (ITAAC) or detailed design documents describe designs, tests, analyses, or other methods of demonstrating that design commitments have been satisfied. Information that is not contained in the licensee’s or applicant’s submittal should be available for review. 3. Acceptance Criteria Purchased PLC hardware; embedded and operating systems software, programming tools, and peripheral components should be qualified to a level commensurate with the system they are designed to support. EPRI TR-106439 and EPRI TR-107330 describe an acceptable