Knowledge about deuterium retention and diffusion in tungsten is important for the design of future fusion reactors. A large number of experiments have been carried out to study the retention of deuterium in tungsten after plasma exposure near room temperature, which is dominated by trapping of deuterium near material defects. The results are usually modeled using diffusion data extrapolated from much higher temperatures, since the dynamic effects of deuterium diffusion in tungsten are difficult to measure near room temperature, due to the very low solubility of deuterium in tungsten. It is thus important to test the validity of this extrapolation and the model used by measuring and modeling of the diffusion dynamics near room temperature. In this talk, a method based on deuterium plasma loading on one side and accumulation of permeating deuterium in a getter layer on the other side of the sample, is presented. The amount of deuterium in the getter is analyzed after the plasma exposure using nuclear reaction analysis. By exposing samples to the plasma for different times, information about the temporal evolution of the deuterium permeation flux and thus the dynamic effects mentioned above can be gained. [mehr]