ISO 27048:2011

Overview

ISO 27048:2011 - Radiation protection - Dose assessment for the monitoring of workers for internal radiation exposure specifies minimum requirements and standardized procedures for evaluating monitoring data from workers potentially contaminated by radioactive substances. The standard provides a framework to quantify internal doses reliably for regulatory compliance and radiation protection programmes, defines applicability limits where more advanced methods are needed, and excludes certain specialist applications (e.g., litigation dosimetry, contaminated-wound dosimetry).

Key technical topics and requirements

• Dose-assessment procedures based on reference levels for routine and special monitoring programmes.
• Selection of dose‑critical parameter values: assumptions and justification for parameter choices used in interpretations.
• Criteria for significance: how to determine whether monitoring results indicate a meaningful internal intake.
• Interpretation of workplace monitoring results, including guidance for combining and comparing results from different measurement methods and times.
• Uncertainty analysis: addressing uncertainties from sampling, measurement techniques and working conditions to support defensible dose estimates.
• Special topics: handling multiple datasets, data below the decision threshold, rogue or outlier data, and calculation of doses to the embryo/foetus and infant.
• Reporting and documentation: minimum documentation and reporting requirements to demonstrate compliance and enable review.
• Quality assurance: requirements to ensure reliable monitoring, measurement and dose-assessment practices.
• Applicability limits: defined dose levels above which more sophisticated modelling or expert methods are required.

Note: ISO 27048:2011 explicitly does not cover dosimetry for litigation, modelling to improve dosimetry methods, effects of decorporation measures (chelation), investigation of causes or implications of an exposure, or contaminated-wound dosimetry.

Practical applications and users

ISO 27048 is intended for organizations and professionals involved in occupational radiation protection, including:

• Health physicists and radiation protection specialists conducting internal dosimetry and exposure assessments.
• Occupational safety managers and employers operating facilities with potential internal contamination (nuclear, medical radionuclide handling, research, industrial radioisotope use).
• Accredited laboratories and service providers performing bioassay, whole-body or in vivo monitoring and dose calculations.
• Regulators and auditors assessing compliance with radiation protection regulations and monitoring programmes.

Practical uses include routine and special worker monitoring, documenting compliance, interpreting mixed-method monitoring results, and establishing defensible dose records for programme management.

Related standards and guidance

ISO 27048 complements national regulations and international radiological protection guidance (e.g., ICRP recommendations) and should be used alongside other ISO radiation‑protection standards and local regulatory requirements to build a complete occupational internal dosimetry programme.

Keywords: ISO 27048, radiation protection, dose assessment, internal radiation exposure, monitoring workers, internal contamination, internal dosimetry, occupational exposure, uncertainty, quality assurance.