This paper presents vented combustion data gathered in a 120 m(3) large scale vented combustion test facility at the Canadian Nuclear Laboratories. Experiments were performed with single volumes (57 or 120 m(3)), or two (60 and 57 m(3) each) and three (25, 28 and 57 m(3) each) interconnected volumes using lean H-2-air mixtures (6-10 vol.% H-2) under the initially quiescent or turbulent conditions. The effects of scaled vent area (AdV(2/3)), number of connected volumes, initial turbulence and hydrogen concentration on dynamics of vented combustion are examined. The test results show that combustion in an interconnected multi-compartment geometry could produce significant flame acceleration and local pressure build-up for mixtures containing 8 vol.% or higher H-2 in air due to flame jet ignition and flame interaction between compartments, resulting in much higher overpressures than in a single volume. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.