DICHTUNGSANORDNUNG FUER EINE WELLE

1. A seal arrangement for a shaft (1) having a main seal which, while the shaft is stationary and while the shaft rotates in smooth operation, prevents a hazardous fluid from escaping from a housing, and having an auxiliary seal which is connected downstream from the said main seal via a space (6a) surrounded by a part (6) of the housing and takes over the sealing function on failure of the said main seal, and is formed by a mechanical seal turning without contact with the shaft rotation in smooth operation, characterized in that the auxiliary seal is formed by a gas-lubricated mechanical seal (2, 5) which, in relation to the pressure in the space (6a), has a K-factor far higher than 1, which is connected to the space (6a) at its outside circumference and which is connected to the free atmosphere (A) at its inside circumference and has open intake grooves (2b) to this inside circumference, the intake grooves (2b) in smooth operation introducing air from the free atmosphere between the sliding surfaces (2a, 5a) and the latter forming separating air cushions of minimum thickness, and in faulty operation the mechanical seal (2, 5), lubricated by the fluid which has entered the space (6a) or in dry rotation, taking over the sealing function.