The communication of risk in general and the potential risk in relation to low doses of ionizing radiation in particular is a complex subject and needs to be scientifically investigated. Internationally recognized organizations like (ICRP, WHO, IAEA etc.) provide a relatively consistent view about radiological risks but there still remains an opposing view to the internationally set safety standards and guidelines. Moreover, uncertainty related to health effects from low doses of ionizing radiation exists. Four interrelated challenges of risk perception and risk communication in the field of low doses of ionizing radiation and the field of medical use of ionizing radiation important for democratic risk governance are discussed in this editorial in order to identify new research topics. First, the issue of technical information and the use of risk estimates; second, the issue of perception and communication related to uncertainty of scientific information; third, the goal of communication by experts and/or authorities; and finally, the role of social networks in the interpretation of risk from low radiation doses. These challenges and research topics were discussed, among others, during the EC FP7 OPERRA research workshop in Brussels, Belgium (2013).