In Finnish legislation, diagnostic reference level (DRL) is defined as a predefined dose level or administrated activity level for a normal-sized patient that are not expected to be exceeded for standard procedures or examinations when good practice is applied. The concept of a DRL was introduced by ICRP in 1996 and the first national DRLs in Finland were published in the year 2000. Since then, the number of the national DRLs has increased and the older ones have been updated, in many cases, numerous times.

Currently the DRLs cover CT examinations (adult and paediatric), nuclear medicine, cone-beam computed tomography of the head and neck region, cardiology and conventional x-ray examinations including dental examinations (adult and paediatric). When applicable, the DRLs are given based on an indication of the examination or a specific procedure and can be classified as clinical DRLs. Currently the oldest DRLs are for the adult CT examinations, which are from 2013. Traditionally the data for establishing the DRLs has been collected by sending the facilities a spreadsheet...

Since the DRLs have been in use in Finland for approximately 20 years, the users of radiation are typically accustomed to the concept and compare their average doses to the DRLs according to the requirements in the legislation. Despite the long history, there is always room for improvement in establishing DRLs. Encouraging the facilities to use automatic dose management systems would increase the number of patient doses to be analysed. A proper national PACS with customised interfaces for facilities and competent authority could enable constantly...

A. Lajunen; Helsinki/FI - nothing to disclose

"Säteilyturvakeskuksen määräys oikeutusarvioinnista ja ja säteilysuojelun optimoinnista lääketieteellisessä altistuksessa," Radiation and Nuclear Safety Authority, April 2019, in Finnish "Reference levels for the patient's radiation exposure for conventional paediatric X-ray examinations," Radiation and Nuclear Safety Authority, April 2018