Monitor the Gamma irradiation of the blood bags
Transfusion-associated graft-versus-host disease (TA-GVHD), a rare complication of blood transfusion, is usually fatal. Patients in certain clinical categories, including bone marrow transplants, solid tumors and acquired T cell defects, are at greater risk of developing TA-GVHD. It can be prevented by the irradiation of cellular blood products prior to transfusion, thus one needs to be sure that the irradiation has been successful for 100%.
The way to be 100% sure is to apply an irradiation label on the bloodbag that changes colour when irradiation was successful!