Section 640.24(b) of 21 CFR requires that *Platelets*  shall be separated within 4 hours after the collection of the unit of whole blood or plasma.
During inspections, questions have arisen concerning blood banks that do not separate the platelets from platelet-rich plasma for a period in excess of 4 hours.
This section of the regulations was promulgated to assure that the red cells are promptly separated from the plasma and refrigerated rather than concern about compromising the quality of the resultant platelet concentrate if the platelets remained in the plasma for a period in excess of four hours.
Based on recommendations received from the Panel on Safety and Efficacy of Blood and Blood Derivatives, the *Center for Biologics Evaluation and Research* is preparing to modify the regulation to indicate that:
- The 4-hour period for separation of plasma from red cells be changed to 6 hours. (Please note--The plasma should be placed in the freezer within 6 hours. 21 CFR 640.34(b), which requires that plasma be frozen solid within 6 hours, will be revised to reflect this change)
- There be no time limit set for the preparation of *platelets* from platelet-rich plasma.
*Platelets*  may be prepared from platelet-rich plasma at any time during the dating period assigned to *platelets,* provided that:
Not more than 6 hours following collection of whole blood, the red cells are separated from the platelet-rich plasma and refrigerated;
The platelet-rich plasma is stored at the appropriate temperature (20-24o C) until the platelets are separated.
Blood banks that prepare *Platelets*  and * * Fresh Frozen *Plasma* consistent with these policy guidelines will not be considered to be deviating from acceptable manufacturing practices.
*Material between asterisks is new or revised*
 Indicates material has been deleted
Revised: 12/1/82, 3/95