You may already know about the ongoing need for blood and the importance of your donations through the American Red Cross. Whole blood donations contain red blood cells, platelets, plasma and white blood cells. Red blood cells are the most frequently used blood component and are needed by almost every type of patient requiring transfusion. If you meet certain criteria, double red cell donation allows you to safely donate two units of red cells during one appointment as an automated donation process. It is as safe as whole blood donation.