in our Blood Bank lab which is the biggest and the main in the country , we do review of BB testing on daily basis, there is a bench called reveiew , after the technician complete all the test will refere the request to review bench , the technician in this bench will check the request starting from ID and test order, the reaction of the test , resulting , documentation of crossmatching, chosin proper blood components thin he release in the system , if there is any mistake he will report to the supervisor and will not release til the mistake will be solved.any cases for further investigation will be referd to technical incharge on the dyty. This bench on the three duty (morning , evening and night).