Skip to main content
Back

EVS-EN IEC 61226:2021

Nuclear power plants - Instrumentation, control and electrical power systems important to safety - Categorization of functions and classification of systems

General information

Valid from 03.08.2021
Base Documents
IEC 61226:2020; EN IEC 61226:2021
Directives or regulations
None

Standard history

Status
Date
Type
Name
03.08.2021
Main
06.05.2010
Main
This document establishes, for nuclear power plants, a method of assignment of the functions specified for the plant into categories according to their importance to safety.
Subsequent classification of the I&C and electrical power systems performing or supporting these functions, based on the assigned category, then determines relevant design criteria.
The design criteria, when applied, ensure the achievement of each function in accordance to its importance to safety. In this document, the criteria are those of functionality, reliability, performance, environmental qualification (e.g. seismic) and quality assurance (QA).
This document is applicable to:
- the functions important to safety that are performed by I&C systems and supported by electrical power systems (categorization of I&C functions),
- the I&C systems that enable those functions to be implemented (classification of I&C systems),
- the electrical power systems that support those functions (classification of electrical power systems).
The systems under consideration provide automated protection, closed or open loop control, information to the operating staff, and electrical power supply to systems. These systems keep the NPP conditions inside the safe operating envelope and provide automatic actions, or enable manual actions, that prevent or mitigate accidents, or that prevent or minimize radioactive releases to the site or wider environment. The I&C and electrical power systems that fulfil these roles safeguard the health and safety of the NPP operators and the public.
This document follows the general principles given in IAEA Safety Requirement SSR-2/1 and Safety Guides SSG-30, SSG-34 and SSG-39, and it defines a structured method of applying the guidance contained in those codes and standards to the I&C and electrical power systems that perform functions important to safety in a NPP. This document is read in association with the IAEA guides together with IEC 61513 and IEC 63046 in implementing the requirements of the IEC 61508 series. The overall classification scheme of structures, systems and components for NPPs can be summarized as follows by Figure 1.

Required fields are indicated with *

*
*
*
PDF
26.84 € incl tax
Paper
26.84 € incl tax
Browse standard from 2.44 € incl tax
Standard monitoring

Customers who bought this item also bought

Main

EVS-EN 61513:2013

Nuclear power plants - Instrumentation and control important to safety - General requirement for systems (IEC 61513:2011)
Newest version Valid from 02.04.2013
Main

EVS-EN IEC 62138:2019

Nuclear power plants - Instrumentation and control systems important to safety - Software aspects for computer-based systems performing category B or C functions
Newest version Valid from 15.10.2019
Main

EVS-EN IEC 62645:2020

Nuclear power plants - Instrumentation, control and electrical power systems - Cybersecurity requirements
Newest version Valid from 17.08.2020
Main + amendment

EVS-EN 50128:2011+A1+A2:2020

Railway applications - Communication, signalling and processing systems - Software for railway control and protection systems
Withdrawn from 01.12.2023