ISO 13408-2:2003 specifies requirements for sterilizing filtration as part of aseptic processing of health care products. It also offers guidance to filter users concerning general requirements for set-up, validation and routine operation of a sterilizing filtration process, to be used for aseptic processing of health care products. ISO 13408-2:2003 is not applicable to removal of viruses. Sterilizing filtration is not applicable to fluids containing particles as effective ingredient larger than the pore size of a filter (e.g. bacterial whole-cell vaccines).