Plastic deformation tests were carried out by helium pressurization in 304 austenitic steel sphere, previously used for tritium permeability experiments at 2000° C but within negligible residual degassing rate room temperature. Important degassing peaks were noted, and we ascribe them to the emergence of tritium-carrying dislocations. The mechanism of Bastien and Azou (1-2) proposes that during fragilization by internal hydrogen, this hydrogen is carried off by the dislocations. This mechanism is now classic; in the last 20 years it has received numerous experimental confirmations, and it has been possible to extend it to the case of cracking by corrosion under stress in austenitic steels (3), and to the case of fragilization by gaseous hydrogen (4). However, in the first case a simple reticular diffusion is insufficient to explain the cracking rates observed, and in the second it does not explain why a metal deformed to the breaking point under hydrogen can absorb quantities of hydrogen of the order of one ppm in a few minutes, at ordinary temperatures. In the present work, we have tried to reveal the role of dislocations in hydrogen transport, using degassing measurements made on a sphere of austenitic steel deformed plastically at 22°, after test of tritium permeability at 200° C.