SIST EN ISO 6980-2:2025

Overview

EN ISO 6980-2:2025 - adopted by CEN from ISO 6980-2:2023 (corrected version 2024-03) - defines calibration fundamentals for reference beta-particle radiation fields used in nuclear energy and radiological protection. The standard specifies methods to measure the absorbed-dose rate in a tissue-equivalent slab phantom for reference beta radiations with maximum beta energies from 0.22 MeV to 3.6 MeV (mean beta energy ~0.07 MeV to 1.2 MeV). It is intended primarily for organizations establishing primary dosimetry capabilities and for laboratories using an extrapolation chamber as a primary standard for beta-particle dosimetry.

Key Topics

• Primary measurement quantity: absorbed dose to tissue at reference depths (0.07 mm and optionally 3 mm) in a tissue-equivalent slab phantom at perpendicular incidence.
• Primary standard: detailed procedures for the use of an extrapolation chamber (extrapolation curves, depth scaling, correction factors).
• Secondary systems: guidance on calibrations with ionization chambers and other measurement systems or geometries (described in less detail).
• Energy range limitation: applies only to beta energies within the stated range; energies outside this range are out of scope.
• Operational quantities: links between measured reference absorbed dose and ICRU/ICRP operational quantities (e.g., directional dose equivalent H′(0.07; Ω), H′(3; Ω), personal dose equivalent Hp(0.07), Hp(3)). Notes that H*(10) and Hp(10) are not appropriate for beta radiation, even for higher-energy betas.
• Calibration traceability and uncertainty: requirements and examples for establishing traceability and for the statement and propagation of measurement uncertainties.
• Supplementary material: normative and informative annexes covering reference/test conditions, chamber correction factors, and an example uncertainty analysis.

Applications

• Establishing national or laboratory primary beta dosimetry capabilities.
• Calibrating and validating beta dosemeters and dose-rate meters used for radiation protection.
• Providing calibration procedures for radiation protection services, nuclear facilities, metrology institutes, and instrument manufacturers.
• Supporting dose assessment where accurate absorbed-dose rate at shallow tissue depths is required (e.g., skin dose evaluation).

Who should use this standard

• National metrology institutes and calibration laboratories
• Radiation protection laboratories and health physics services
• Nuclear industry calibration units
• Manufacturers of beta dosimetry equipment and extrapolation chambers

Related Standards

• ISO 6980-1 (reference radiation production and characterization)
• ISO 6980-3 (calibration of dosemeters and dose-rate meters)
• ISO 29661 (reference radiation field concepts)
• ISO/IEC Guide 99 (VIM - metrology vocabulary)
• ICRU Report 56 (discussion on operational quantities for beta radiation)

Keywords: EN ISO 6980-2:2025, reference beta-particle radiation, beta dosimetry, extrapolation chamber, absorbed-dose rate, tissue-equivalent slab phantom, calibration, measurement uncertainties, primary standard, CEN.