This paper presents the experimental results of utilizing Electro-Osmotic Pulsing Technology to reduce the diffusion of radon soil gas through a concrete slab. A laboratory system with state-of-the-art instrumentation has been used to measure the diffusion coefficient of radon soil gas through 30.5 cm diameter, 10.2 cm thick standard composition concrete samples (w/c = 0.5 and cement:sand:gravel = 1:2:4). Within these concrete samples, a triple titanium anode configuration is embedded while an external copper rod is used as the cathode. To complete the circuit, these electrodes are connected to a unique variable pulsating power supply. This unique control processor generates a variable waveform sequence of positive, negative and neutral applied voltages with a variable pulse duration and current amplitude. In the test apparatus, the Source Chamber is filled with Antigo Silt Loam Soil, typical of Wisconsin soils and a passive radon gas source. The concrete sample is placed between this Source Chamber and a Collection Chamber so that the frontal facial area of the concrete sample is adjacent to the soil and radon gas flux. The rear facial area of the concrete slab is exposed to quiescent air. The experimental results show as much as a 93% reduction in the radon soil gas diffusion coefficient through the concrete slab when the Electro-Osmotic Pulsing System (EOPS) is in operation. The effects of system operation, voltage waveform sequence, pulse duration as well as soil and concrete relative humidity levels are documented. Details of the innovative experimental system and procedures are described. The results of this study have indicated that Electro-Osmotic Pulsing Technology should be considered as an effective and alternative method of reducing radon soil gas diffusion in buildings.