New ISO standard to protect workers exposed to radiation

A new ISO standard will help optimise individual monitoring and protection of workers exposed to radiation. It will also provide the technical basis for reinforcing regulation in this field worldwide. The application of ISO 27048:2011 ‘Radiation protection - Dose assessment for the monitoring of workers for internal radiation exposure’ will contribute to more reliable and consistent results when measuring internal doses of radioactive substances.

Many workers are exposed - often in varying degrees and circumstances - to ionising radiation. Therefore, people who are occupationally exposed to ionising radiation receive increased health surveillance and monitoring. For workers exposed to radioactivity which may enter the body via inhalation, ingestion or the skin, a comprehensive monitoring program is needed; such a program consists in measurements of body activities and excretion rates via urine or faeces.

The quantitative interpretation of such measurements requires well-defined models and data describing the behaviour of radioactive substances in the human body. Various comparative studies have revealed that, in spite of the availability of scientific support in the form of International Atomic Energy Agency (AEIA) and International Commission on Radiological Protection (ICRP) recommendations, the actual application of identical models and data by different laboratories often results in dose assessments differing by orders of magnitude.

There is, therefore, a need to lay down standard procedures for assessing internal doses using exposure data, in order to achieve consistency and reliability in the assessment of doses. ISO 27048:2011 should:

• Improve the reproducibility of dose assessments;
• Ensure that the level of effort required for data interpretation is commensurate with the seriousness of the exposure;
• Enable the exchange of consistent dosimetric information among laboratories and authorities, including across international borders.

This International Standard specifies the minimum requirements for the evaluation of data from the monitoring of workers and presents procedures and assumptions for the standardised interpretation of monitoring data, in order to achieve acceptable levels of reliability. Those procedures allow the quantification of radiation exposures for the documentation of compliance with regulations and radiation protection programs.

ISO 27048:2011 will be useful in interpreting data and assessing the reliability of results and will thus help improve the protection of workers through better knowledge of internal doses of radioactive substances.

This International Standard is one of a series of three standards that together form a complete and consistent system regulating the complex issue of monitoring workers for potential incorporations (measurement programs, requirements for laboratories, quantitative assessment of exposures).