time enough to let all platelets and about 50 ml of plasma to transfer to the platelets bag in order to remove all platelets efficiently from the plasma bag it is preferable to open and close the platelets valve 76 intermittently until all platelets exit the plasma bag in small bursts of 1 ml of platelets concentrate as it is explained in the teaching above intermittent opening and closing of the valve allows the platelets layer to be reshaped and enhances the sharpness of the separation edge between plasma and platelets this practice keeps on accumulating high concentration of platelets at the exit port ready to exit the plasma bag when the valve is opened after completing certain number of platelets valve opening and closing cycles that ensures the depletion of platelets in the plasma bag the volume of the fluid that exits at each cycle is increased the valve continues with the intermittent open and close cycles but the exiting fluid volume is increased in order to drive about 50 ml of plasma to the platelets bag this routine permits the residual platelets or residual leukocytes to exit the plasma bag with each portion of plasma that transfers to the platelets bag per cycle after separating blood components and isolate each component in an individual bag centrifuge rotor spins at low speed at this stage the system is ready to start component treatment task depending on the selected protocol the system proceeds with the treatment details associated with the selected protocol if rbc treatment for up to 42 days storage is selected the system proceeds by mixing the rbc concentrate with additive solution the pressure is partially decreased in the.