SIST EN IEC 62705:2026

Overview

SIST EN IEC 62705:2026 addresses the requirements for the lifecycle management of Radiation Monitoring Systems (RMS) important to safety in nuclear facilities. Developed by the International Electrotechnical Commission (IEC) and adopted as a Slovenian standard, this document ensures harmonization with the latest international best practices in monitoring and controlling radiation in nuclear environments. Applicable to systems used during normal operations, anticipated operational occurrences (AOO), design basis accidents (DBA), and design extension conditions (DEC) including severe accidents (SA), the standard provides comprehensive guidance for design, qualification, calibration, integration, and ongoing management of RMSs.

The revised 2026 edition aligns with updated accident categorization, references the most recent standards, and updates terminology, supporting safe, effective, and compliant radiation monitoring throughout all phases of nuclear facility operation.

Key Topics

• Lifecycle Management of RMS
  The document establishes strict guidelines for managing RMS throughout their lifecycle, from initial specification and design through installation, operation, modification, and decommissioning.

• Integration with Existing Standards
  SIST EN IEC 62705:2026 maps its requirements to existing IEC and ISO standards, covering:

  • Design and qualification processes (hardware and software)
  • Calibration and traceability for radiation monitors
  • Sampling of radioactive materials
  • Categorization and classification of safety functions

• Accident Condition Coverage
  RMSs must be operable and reliable not only during routine operation but also under abnormal and extreme accident conditions, including severe accidents, to ensure ongoing safety and regulatory compliance.

• Categorization and Classification
  The standard defines systematic approaches for RMS function categorization and system classification, ensuring that each system is appropriately designed and qualified for its safety significance in compliance with IEC 61226 and related standards.

Applications

• Nuclear Power Plants
  RMSs designed and managed under this standard provide essential radiation surveillance to protect personnel, the environment, and infrastructure, supporting core regulatory and operational objectives across all nuclear plant conditions.

• Nuclear Fuel Storage and Processing Sites
  Effective radiation monitoring is critical for safety assurance in fuel storage facilities, reprocessing plants, and other nuclear installations, enabling prompt detection of radiological risks.

• Facility Design and Retrofit
  Engineering teams apply REQUIREMENTS from SIST EN IEC 62705:2026 when designing new monitoring systems or upgrading existing infrastructure. This ensures RMSs meet current safety, calibration, qualification, and integration requirements from project inception through operational life.

• Accident Preparedness and Response
  The comprehensive framework supports robust emergency preparedness by specifying RMS performance during both expected and extreme events, enabling facilities to maintain regulatory compliance and minimize radiation exposure risks in all scenarios.

Related Standards

SIST EN IEC 62705:2026 is fully integrated within the international framework of nuclear safety and radiation monitoring, referencing and aligning with key standards, including:

• IEC 61513: General requirements for instrumentation and control systems important to safety in nuclear power plants
• IEC 61226: Categorization of functions and classification of systems
• IEC 60880 / IEC 62138: Software aspects for computer-based systems performing category A, B, or C safety functions
• IEC/IEEE 60780-323 & 60980-344: Environmental and seismic qualification of safety-related equipment
• IEC 60768 / IEC 60861 / IEC 61031: Requirements for specific types of radiation monitoring equipment
• ISO/IEC 17025: Competency requirements for testing and calibration laboratories
• ISO 2889: Sampling airborne radioactive materials

By following SIST EN IEC 62705:2026 and these related standards, nuclear facilities ensure the reliability, traceability, and compliance of their radiation monitoring systems, ultimately supporting operational safety and regulatory conformity across the nuclear sector.