Predicting the loads of electrical devices is an important part of modeling the energy flows in buildings. In non-residential buildings these loads can have a significant impact on heating and cooling requirements. In the case of hospitals this holds true particularly for areas directly connected to diagnostics and medical treatment. Even though the amount of information concerning these loads has increased in recent years, detailed information based on measured data remains scarce. Thus, within this paper over 20,000 h of measured data for operating theaters, intensive care units, examination and treatment rooms as well as large scale medical equipment are analyzed and evaluated. The used methodology allows for the determination of area-specific operating hours and a prediction of time-dependent electrical loads in different hospital departments. It was found that a differentiation of weekdays and weekend days is not appropriate for intensive care units, while the examined operating suites show surprisingly strong similarities with regular "office hours" within the assessed hospital. The presented values extend findings from other recent studies in this field and give a more detailed separation of individual contributions from lighting and different classes of medical equipment. (C) 2016 Elsevier B.V. All rights reserved.