IEC 61757-1-2:2023

Overview

IEC 61757-1-2:2023 defines the specifications for distributed strain measurement using fibre optic sensors based on Brillouin scattering. As part of the internationally recognized IEC 61757 series, this standard targets distributed strain sensing systems (DSS) that leverage spontaneous or stimulated Brillouin scattering to measure absolute strain along optical fibers. By establishing key performance parameters and standardized measurement procedures, IEC 61757-1-2:2023 enables consistent evaluation, documentation, and deployment of advanced fibre optic strain sensing solutions.

Key Topics

• Distributed Fibre Optic Strain Sensing: Systems that utilize optical fibers connected to an interrogation unit to provide spatially resolved, continuous strain measurements along the sensor length.
• Brillouin Scattering: The underpinning technology for DSS, using either spontaneous or stimulated scattering effects to determine strain distribution.
• Performance Parameters:
  • Strain measurement error
  • Spatial resolution
  • Strain repeatability
  • Spatial strain uncertainty
  • Warm-up time
  • System performance under varying attenuation
• Test Setups: Requirements for general setups, including the use of temperature chambers, fiber configurations (single-ended and loop), and appropriate calibration tools.
• Documentation Protocols: Comprehensive recording of measurement and setup details to ensure traceability and repeatability.
• Measurement Procedures: Step-by-step guidelines for determining each DSS performance characteristic under controlled environmental and operational conditions.

Applications

IEC 61757-1-2:2023 is highly relevant for industries and applications where precise, long-range monitoring of structural strain is critical. Common use cases include:

• Civil Infrastructure: Continuous monitoring of bridges, tunnels, dams, and buildings for structural health, detecting deformation or potential failure points.
• Energy Sector: Surveillance of pipelines, wind turbines, and power plants to identify strain-induced anomalies that could impact safety and efficiency.
• Geotechnical Engineering: Subsurface strain monitoring in landslide-prone or seismically active regions.
• Industrial Environments: Smart manufacturing lines and mechanical systems where real-time strain metrics enable predictive maintenance and process optimization.

The standardized approach ensures interoperability, reliability, and accuracy, which are essential for regulatory compliance and operational safety in these critical sectors.

Related Standards

For organizations seeking to implement or expand their use of fibre optic sensor technology, the following related IEC standards provide valuable additional guidance:

• IEC 61757:2018 - Generic specification for fibre optic sensors
• IEC 61757-2-2:2016 - Temperature measurement with distributed sensing
• IEC 61757-3-2:2022 - Acoustic sensing and vibration measurement
• IEC 60869-1 - Fibre optic passive power control devices
• ISO/IEC Guide 98-3 - Guide to the expression of uncertainty in measurement (GUM)

Incorporating these standards supports a robust, cohesive approach to sensing solutions for both new and existing infrastructure and technology deployments.

By adhering to IEC 61757-1-2:2023, industry stakeholders benefit from harmonized terminology, proven methodologies, and clearly defined performance benchmarks, aiding in the reliable selection, deployment, and management of fibre optic distributed strain sensing systems based on Brillouin scattering.