Recently we had an incident where the timer setting on the Irradiator was 6min 1sec, but the print out had 6min 2sec. The calculated time for the 27.5 Gy for central dose rate( the Radiation Officer adds 10% to minimum central dose of 25Gy) is 6min 1sec At the 25Gy dose it would be 5min 31sec. But, what would be the maximun acceptable Gy central dose for blood and blood products? (Cesium-137 source) Anyone have any similar problems or any suggestions?