ISO Standards to help manage risk of exposure to radon

Issue 45 – December 2012

A new series of ISO Standards will help to assess the radiation exposure to natural radioactivity in the environment and buildings, particularly radon, which is considered the second cause of lung cancer after smoking in many countries. Radon is reported by the World Health Organization (WHO) to cause between 3 – 14% of such disease worldwide.

ISO 11665:2012 Measurement of radioactivity in the environment – Air: radon-222, published in several parts, outlines guidance to measure radon-222 activity concentration and the potential alpha energy concentration of its short-lived decay products in the air.

Roselyne Ameon, project leader of the series of Standards comments, 'By proposing standardised measurement methods for testing laboratories, the ISO 11665 series of Standards will help to reduce health risks due to exposure to radon in taking measures for preventing and mitigating radon effect. Radon measurements in homes are easy to perform, but need to be based on standardised protocols to ensure accurate and consistent measurements. Quality assurance and quality control measures are strongly recommended to assure the reliability of radon test results.'

'Radon is a chemically inert, naturally occurring radioactive gas. It has no smell, colour, or taste. Radon is produced from the natural radioactive decay of uranium, which is found in rocks and soil. Radon escapes from the ground into the air, where it disintegrates through short-lived decay products called radon progeny. As radon progeny decay, they emit radioactive alpha particles and attach to aerosols, dust, and other particles in the air. As we breathe, radon progeny are deposited on the respiratory tract and can cause cancers.'

The ISO 11665 series of Standards provides several testing methods. Selection of the appropriate method will depend on the intended use of the data and the site under investigation, such as underground mines, outdoors, houses, buildings open to the public, workplaces, and so on.

ISO 11665 consists of the following parts, under the general title; Measurement of radioactivity in the environment – Air: radon-222:

  • Part 1: Origins of radon and its short-lived decay products and associated measurement methods

  • Part 2: Integrated measurement method for determining average potential alpha energy concentration of its short-lived decay products

  • Part 3: Spot measurement method of the potential alpha energy concentration of its short-lived decay products

  • Part 4: Integrated measurement method for determining average activity concentration using passive sampling and delayed analysis

  • Part 5: Continuous measurement method of the activity concentration

  • Part 6: Spot measurement method of the activity concentration

  • Part 7: Accumulation method for estimating surface exhalation rate

  • Part 8: Methodologies for initial and additional investigations in buildings

The following parts are in preparation:

  • Part 9: Method for determining exhalation rate of dense building materials

  • Part 10: Determination of diffusion coefficient in waterproof materials using activity concentration measurement

  • Part 11: Test method for soil gaz.

The measurement results will notably help to ensure compliance with the WHO recommendations on the reduction of indoor radon concentrations; 'WHO recommends that countries implement national programmes to reduce the population's risk from exposure to the national average radon concentration, and to reduce the risk for individuals exposed to high radon levels. Building codes should be implemented to reduce radon levels in homes under construction.'

Note: You can order ISO and IEC Standards from www.standards.co.nz or call 0800 782 632 during business hours or email enquiries@standards.co.nz. Members of Standards New Zealand receive a 20% discount on all NZS and AS/NZS Standards, and a 10% discount on all international Standards. Visit our membership page for more information.

View the ISO 11665 series

Summarised from an ISO media release, 29 November 2012.

Published in international.