Metrology in the context of ionizing radiation regulatory bodies

Abstract

This paper analyzes the role of metrology in the regulation of activities involving ionizing radiation in Brazil, highlighting its relevance in ensuring the reliability of measurements used in regulatory processes. The regulation of these activities is carried out by different governmental bodies, particularly the National Nuclear Safety Authority (ANSN), the Brazilian Health Regulatory Agency (ANVISA), and the Ministry of Labor and Employment, and is based on three main stages: the establishment of standards and regulations, licensing and authorization processes, and inspections and audits. In all these stages, metrology plays a central role by ensuring comparability and traceability of measurement results. The paper also discusses the integration of the Brazilian metrological infrastructure into the international context, emphasizing the importance of institutions and agreements such as the BIPM, ILAC, OIML, and the CIPM MRA, which are responsible for ensuring the international recognition of measurement standards and results. At the national level, the role of the National Institute of Metrology, Quality and Technology (INMETRO) is highlighted as the body responsible for coordinating the Brazilian metrological system, as well as the role of the National Laboratory of Ionizing Radiation Metrology (LNMRI) as the designated laboratory for ionizing radiation. In addition, the paper analyzes the operational measurement infrastructure in Brazil, which includes calibration laboratories, testing laboratories, individual monitoring services, and radiometric analysis laboratories, all linked to accreditation networks coordinated by Cgcre/Inmetro and CASEC. In this context, the reliability of measurements depends on metrological traceability to the International System of Units (SI) and on the proper integration of the different levels of the metrological infrastructure. Finally, it is concluded that although Brazil has a robust metrological infrastructure aligned with international standards, there is still no evidence that the installed capacity is sufficient to fully meet national demand. Therefore, the need for systematic assessments of the existing infrastructure and for strengthening actions aimed at ensuring metrological traceability and radiological safety in the country is emphasized.