UV radiation is part of the electromagnetic spectrum. For practical reasons, applications are categorized according to whether the UV radiation comes from natural or artificial sources. Physically, there is no difference, but the spectral composition of artificial sources can vary greatly. Humans are relatively well adapted to the natural solar UV spectrum. Nevertheless, there are a number of positive and negative effects of exposure to UV radiation. These must be taken into account in the risk assessment and workplaces must be designed to be safe—both inside and outside buildings. In recent years, knowledge about UV radiation during outdoor activities has increased considerably, as both international interest groups and social insurance organizations and legislators have taken up the issue. Occupational safety and health research and occupational medicine have also dealt with the topic intensively. Now, there are well-founded instruments for retrospective calculation of UV radiation, as well as detailed registers for research into occupationally related UV radiation information. Prevention must be thought of and implemented holistically. Both situational and behavioral preventive measures are available for this. It is crucial that both employees and employers live up to their responsibilities.