Since 2014, HERCA organised three workshops with direct relevance to the requirements of the BSS directive regarding Radon, NORM and building materials.

These workshops raised different issues including the need to compare national approaches and to exchange on technical issues. 

HERCA Board approved the creation of a new working group dealing with natural radiation sources late 2017. 

This new working group on natural radiation sources met in January 2018 in Paris. Its related mandate and action plan were approved by HERCA Board in May 2018.

A new workshop will be held on National Radon Action Plans - 23rd - 25th March 2021 in Bucharest, Romania.


  • To exchange and compare the different national approaches developed in the framework of the implementation of the BSS directive and associated European directives and regulations with regard to natural ionising radiations.
  • To develop approaches on specific issues focused on radon, NORM and building materials respecting national conditions and legislations.
  • To identify and develop an exchange of knowledge and experiences with relevant stakeholders, including the European Commission.

Action Plan

  • To organise the follow-up of the three workshops organised on Radon, NORM and building materials.
  • To develop a platform of exchange between HERCA members for sharing information on the national regulation with regards to implementation of specific BSS directive requirements on radon, NORM and building materials.
  • To work on specific issues as:
    1. The identification of the consequences of the new radon dose conversion factors at a national level and to work towards identifying options to dealing with them.
    2. The impact of standardization works on national regulations with regards to building materials. To develop relations with CEN and exchange with EC (Art. 31 GoE WP NAT).
    3. To scope out a review of the EC Guidance 122, part. 2 considering the on-going revision work undertaken by IAEA.
  • To continue to explore:
    • The comparison of approaches of the application of optimization to NORM activities, in particular to waste/residue management.
    • Commodities (clothes, etc.) containing NORM
    • An exchange on National inspection frameworks with regard to NORM activities and Radon in workplaces.
  •  To identify and develop exchanges of knowledge and experiences with relevant stakeholders: EC, CEN, ICRP, IAEA, WHO, UNSCEAR, IRPA, ERA (European Radon Association), ENA (European NORM Association)

Mrs Jelena Mrdakovic (DSA, Norway) is the chair and Mr Wolfang Ringer (AGES, Austria) is the co-chair of the working group on natural radiation sources (WGNAT).

For additional information: