[en] Rock samples from three candidate sites for nuclear waste repositories at Olkiluoto, Kivetty and Romuvaara in Finland were analysed by He-gas methods, and their porosities, diffusivities and permeabilities were determined. The throughdiffusion method was used to determine the porosities and effective diffusion coefficients of the short drill-core samples, and the permeability method to measure their permeability coefficients. The channelflow method was used to determine the products of porosity and effective diffusion coefficient for the long drill-core samples. The matrix porosities and effective diffusion coefficients determined are for helium in samples saturated with nitrogen gas