A novel approach to studying dynamic three phase systems using Electrical Capacitance Volume Tomography (ECVT) is proposed and verified against previously published pressure gauge techniques and hydrodynamics patterns. In this three-phase study, hold up of water, glass beads, and air are measured simultaneously in a slurry bubble column reactor. Application of ECVT to investigate three phase systems holds several advantages over pressure gauges including the ability to deliver non-invasive real time direct measurements without making assumptions about the hydrodynamics. Results support the conclusion that ECVT can be used in place of pressure gauges to obtain accurate holdup measurements of three-phase flow systems in real time applications. (C) 2019 Elsevier B.V. All rights reserved.