EN IEC 62705:2026

Overview

EN IEC 62705:2026 specifies the requirements for the lifecycle management of radiation monitoring systems (RMS) important to safety at nuclear facilities. Developed by CLC and aligned with IEC 62705:2022, the standard provides comprehensive guidance on the design, application, qualification, and maintenance of RMSs, ensuring ongoing safety for operations, anticipated operational occurrences (AOO), design basis accidents (DBA), and design extension conditions (DEC), including severe accidents (SA). The standard also harmonizes with updated international and European requirements, making it a foundational reference for nuclear power plants and other related facilities that depend on reliable radiation monitoring solutions throughout the system lifecycle.

Key Topics

• Lifecycle Management: Outlines RMS activities spanning conception, design, installation, operation, modification, and decommissioning to achieve consistent performance and compliance through all operational phases.
• System Requirements: Aligns with IEC and ISO standards for the qualification, categorization, and classification of RMSs, addressing design, installation, hardware/software integration, and calibration.
• Functional Coverage: Defines requirements for RMSs during all operational states-normal operation, AOO, DBA, DEC, and SA.
• Reference to International Standards: Incorporates and updates normative references, ensuring RMSs are designed to the latest safety, performance, and calibration standards.
• Accident Condition Categorization: Ensures RMSs are specified consistently for use during diverse operating and accident scenarios, reflecting current nuclear safety practices.
• Calibration and Validation: Establishes guidelines for both initial and periodic calibration of RMS, as well as traceability and functional checks to ensure reliable radiation detection and measurement.
• Modification and Upgrades: Provides guidance on systematically managing design changes and upgrading RMSs to maintain compliance with evolving safety standards.

Applications

EN IEC 62705:2026 is applicable to a wide range of radiation monitoring systems across various nuclear facilities, including:

• Nuclear Power Plants: For area, process, effluent, and centralized RMSs vital for reactor safety, environmental monitoring, and emergency response systems.
• Fuel Storage and Processing Sites: Ensures RMSs monitor airborne and liquid effluents, deliver rapid alerts, and enable effective contamination control and exposure assessment.
• Incident and Accident Monitoring: Guides the implementation of RMS designed for high-reliability operation during severe and extended accident scenarios, helping operators make informed decisions to protect personnel, the public, and the environment.
• Regulatory Compliance: Supports utilities and regulatory bodies in demonstrating adherence to international and national nuclear safety requirements in radiation monitoring.
• System Designers and Evaluators: Assists engineering teams, safety analysts, and system integrators in developing, qualifying, and validating RMS to ensure robust performance.

Related Standards

EN IEC 62705:2026 references a suite of interconnected standards to provide a holistic framework for RMS in nuclear facilities:

• IEC 61513: General requirements for I&C systems important to safety in nuclear power plants.
• IEC 61226: Categorization of functions and classification of safety systems.
• IEC 60880 & IEC 62138: Software aspects for computer-based safety functions.
• IEC 60761 series: Requirements for monitoring radioactivity in gaseous effluents.
• IEC 60861 & IEC 61031: Specifications for monitoring in liquids and area gamma monitoring.
• IEC/IEEE 60780-323 & 60980-344: Qualification for environmental and seismic aspects.
• IEC 62003: Electromagnetic compatibility testing.
• ISO 2889 & ISO 4037 series: Sampling techniques and calibration for radiation monitors.
• IEC 60951 series: Radiation monitoring in accident and post-accident conditions.
• IEC 61559, IEC 61504, IEC 60960: Requirements for centralized and plant-wide RMS, including safety parameter display.

This interconnection ensures EN IEC 62705:2026 delivers a consistent and reliable approach to RMS lifecycle management, supporting nuclear safety, operational efficiency, and regulatory compliance.