The new, extended safety requirements for cell separators call for a new generation of machines to address current safety needs. In order to ensure safe treatment, the complete safety concept is of decisive importance - this includes closed seal-less systems, continuous operation, fractions collected externally to the centrifuge, and pump tubings, connections and clamps which are color and direction coded. 'Human failure' as a cause of fault should be excluded for these highly technical appliances - for example, through the use of 'fail-safe' circuits, drip-controlled ACD flow by a separate adjustable pump, detection of damages to blood components by hemolysis control.