Abstract: An installation includes a high pressure steam turbine module, a medium pressure steam turbine module, and at least one low pressure steam turbine module, sealing devices being positioned between a rotating turbine shaft and corresponding casings of the various turbine modules, each of the modules include a main chamber in which the turbine is housed. The installation also includes a first collection chamber positioned in the casing of the high pressure module to collect the steam leaks leaving the high pressure module through its sealing device at a pressure greater than atmospheric pressure, and an injection chamber positioned in the casing of the low pressure module and connected by a first circuit to the first collection chamber such that the steam is transferred from the first collection chamber toward the injection chamber, and then toward the main chamber of the low pressure module through its sealing device.