Fifth generation wireless communications will exploit the enormous chunk of bandwidth available at millimeter-wave frequency bands. Accordingly, an accurate and simple path loss model is critical for indoor environments, where deployment is likely to occur.We conducted measurement campaigns in the 14 and 22 GHz frequency bands in a typical indoor corridor environment on 5th oor of the Discipline of Electrical, Electronic and Computer Engineering building, University of KwaZulu-Natal, Howard Campus, South Africa. This paper presents details of measurement campaigns with unique transmitter receiver combinations using a costume-designed channel sounder. The acquired measurement results provide large- scale path loss statistics in an open-plan indoor environment in line-of-sight and non-line-of-sight conditions. An effective application of dual slope single-frequency directional large-scale path loss model is evaluated based on the acquired measurement data. The application of dual slope large-scale path loss model is supported by a comprehensive analysis and consideration of propagation mechanisms, such as re ection and diffraction resulting in modal attenuation. Validated results show that dual slope large-scale path loss model applied in this paper outperforms close-in reference distance model that assumes the impact of propagating wave guiding effect in indoor corridors.