Bidirectional flow air turbines are used in association with oscillating water columns to convert wave energy available in the oceans into mechanical power. Radial turbines, among others, were studied for such an application. The efficiency of radial turbines using reaction blading was found to be extremely low. On the other hand, the efficiency of impulse-type radial turbines was found to be higher. However, detailed performance studies on impulse-type radial turbines are not found in the literature. This paper presents detailed performance characteristics as well as some parametric studies based on laboratory experiments.