Sterilisation method for a hollow fibre membrane filter

A method for sterilizing a hollow fiber membrane filter having a plurality of hollow fiber membranes sealed at the ends in the housing of the hollow fiber membrane filter so that a first compartment involving the interior of the hollow fiber membranes and a second compartment involving a space between the hollow fiber membranes is formed, wherein the hollow fiber membrane filter has at least two fluid inlets connected to the first compartment and has at least two fluid inlets connected to the second compartment, and wherein the fluid inlets are configured to be connected to a sterilization device, said method comprising at least the steps of:

• a) rinsing the hollow fiber membrane filter with a fluid wherein the rinsing fluid is passed through the first and second compartments of the hollow fiber membrane filter via a selection of the fluid inlets,
• b) carrying out a leakage test,
• c) sterilizing the hollow fiber membrane filter with a sterilizing fluid, wherein the sterilizing fluid is passed through the first and second compartments of the hollow fiber membrane filter via a selection of the fluid inlets,
• and wherein the leakage test is carried out prior to the sterilizing step.