Radiation Dosimetry and Radiobiology Unit


The Radiation Dosimetry and Radiobiology Unit is the oldest professional and technical service for the protection from ionising radiation in the Republic of Croatia. We have worked in this field since 1959. Personal dosimetry surveillance is performed by means of thermoluminescent dosimeters (TLD) on a modern Panasonic dosimetry system.

After fulfilling the strict criteria of the Croatian Accreditation Agency, in 2011 the Unit became an accredited laboratory for testing in the field of ionising radiation. In 2012, the accreditation was supplemented and expanded from “Determining Hp(10) by thermoluminescent dosimeters” to “Determining the speed of the ambiental (outdoor) dose equivalent; H*(10)/t”.

The Unit comprises highly-qualified professionals and engineers of physics with years of experience in the field of radiation protection. Continuous professional and scientific growth and the most advanced measurement equipment have enabled the Unit to become renowned both domestically and internationally. Apart from professional activities, employees of the Unit also partake in domestic and international research projects, thus contributing to the field of radiation protection.


Tests on sources of ionising radiation imply a set of procedures for quality control relating to the functioning of electrical devices that emit ionising radiation (X-ray devices, computerised tomography (CT) devices, bone densitometry devices (densitometers), linear accelerators, etc.) and open and sealed radioisotopes. Quality control procedures include testing relevant parameters that influence safety during the handling and operation of the previously mentioned radiation sources for the people who work with them. Tests on ionising radiation sources are performed:

  1. prior to their initial use;
  2. at least every twelve months, pursuant to provisions on protective measures relating to ionising radiation protection and programmes of quality assurance and maintenance for performing activities involving ionising radiation sources;
  3. after major repairs, alterations or part replacements that could significantly affect the production of ionising radiation and before reintroduction into use;
  4. before use at a new location, if the ionising radiation sources had been transferred from place to another;
  5. after each architectural or building intervention on a space where an ionising radiation source is located that could negatively impact protection from ionising radiation within and outside the space.

Radiation source testing is performed for legal entities with approval for activities involving radioactive sources or electrical devices that emit ionising radiation, obtained from the State Office for Radiological and Nuclear Safety (DZRNS). Upon obtaining this approval, the legal entity must also obtain a procurement approval for an open/sealed radioactive source. After procuring a sealed radioactive source, it has to be registered with the DZRNS, which also applies to X-ray devices (or other electrical devices that emit ionising radiation). Applications for the abovementioned approvals must include the requested appendices, all of which are available at the website of the State Office for Radiological and Nuclear Safety.

Personal dosimetry surveillance includes measurements of external exposure to ionizing radiation for exposed workers or persons in training or education for work with ionising radiation sources. These measurements are performed using thermoluminescent dosimeters (TLDs), according to our own, accredited, methodology. The value measured and reported is called a personal dose equivalent Hp(10). Personal dosimetry surveillance also encompasses a set of procedures that ensure accuracy and reliability of measurements.

The procedure for initiating personal dosimetry surveillance begins by signing an Agreement on Personal Dosimetry Surveillance between the legal entity that employs the exposed worker and the Institute for Medical Research and Occupational Health and registering the exposed worker with the State Office for Radiological and Nuclear Safety (DZRNS) via a registry form and all necessary appendices. Personal dosimeters for the upcoming measurement period alongside instructions on use are then sent by mail. Once a measurement period expires (approx. one month) and an exposed worker receives a new one, he/she must send the previously worn dosimeter back to the Institute for processing. After the received dosimeter is analysed, a dosimetry report is drafted and the radiation dose received is entered into the DZRNS database. The Institute sends out dosimeters every first Monday in a month.

In cases when the radiation dose exceeds the limit values for an exposed worker or is in any other way suspicious, the Institute initiates a procedure to determine the reason, which involves testing the accuracy of the dosimeter itself as well as verifying its contact with the surveyed person. All quality assurance procedures during dosimetry surveillance are performed continuously in order to ensure maximum quality and accuracy.

The Radiation Dosimetry and Radiobiology Unit is an authorised professional and technical service for performing the following activities in the field of ionising radiation protection in the Republic of Croatia:

  • measuring the personal external irradiation of workers or persons in training or being educated to work with sources of ionising radiation (thermoluminescent dosimeters, TLD);
  • testing X-ray machines, accelerators, and other devices that produce ionising radiation, and issuing risk assessments;
  • testing sealed radioactive sources and devices with closed radioactive sources, and issuing risk assessments;
  • testing open radioactive sources and issuing risk assessments;
  • testing spaces where sources of ionising radiation are used and issuing assessments of the level of protection.

Alongside these services, which cannot be performed without official approval from the State Office for Radiological and Nuclear Safety, the Unit also provides the following services from the field of ionising radiation protection:

  • assistance to those that need permission to use sources of ionising radiation from registering to obtaining a license;
  • estimations of the thickness of protective walls in spaces where sources of ionising radiation are used;
  • drafting legislation on the structure and implementation of measures for ionising radiation protection;
  • risk analyses;
  • drafting assessments on purchasing sources of ionising radiation;
  • drafting studies and expert reports (with the authorisation of the Ministry of Environmental and Nature Protection);
  • expert studies on exposure to ionising radiation;
  • expert legal reports;
  • electronic dosimetry;
  • measuring the environmental dose equivalent H*(10) by using thermoluminescent and electronic dosimeters.

Other services:

  • measuring electromagnetic field levels for various sources (mobile telecommunication base stations, power transformer stations, radars, etc.);
  • studies on the impact of EM fields on the environment;
  • measuring asbestos in the environment and issuing assessments, studies…

In the Republic of Croatia, the field of ionising radiation protection is regulated by the Radiological and Nuclear Safety Act (OG 141/13) and other subordinate legislation, all of which are available here.




Our clients include:

Klinički bolnički centar Zagreb
Klinička bolnički centar “Sestre Milosrdnice”, Zagreb
Medicinski fakultet Sveučilišta u Zagrebu
Zavod za javno zdravstvo “dr. Andrija Štampar”, Zagreb
CROSCO d.o.o. član INA grupe, Zagreb
Dom zdravlja Splitsko-dalmatinske županije
Stomatološka poliklinika “Perkovčeva”, Zagreb
Poliklinika Nemetova, Zagreb
Bolnica za ortopedske bolesti i rehabilitaciju „dr. I. Horvat”, Rovinj
Državni zavod za radiološku i nuklearnu sigurnost, Zagreb
Sabor RH
Opća bolnica Varaždin
Opća bolnica “dr. Tomislav Bardek”, Koprivnica
Opća bolnica Virovitica
Opća bolnica Gospić
Opća bolnica Karlovac
Specijalna bolnica za ortopediju i opću kirurgiju dr. Nemec, Matulji
Psihijatrijska bolnica Rab
Dom zdravlja Dubrovnik
Dom zdravlja Ogulin
Dom zdravlja Senj
Dom zdravlja Županja
Zračne luke u RH
Đuro Đaković d.d.
Uljanik brodogradilište
Vivera d.o.o.
AKD Zaštita d.o.o.
Securitas Hrvatska d.o.o.
Osram d.o.o.
Cineplexx HR d.o.o.
Lagermax AED Croatia d.o.o.
Blitz Cinestar d.o.o.
Dcinex d.o.o.

Various private medical practices, dental medicine practices, and many others…