A nominal 2 inch (5 cm), EMI Type 9789B, photomultiplier tube. The 13 stage tube measures 12 cm in length and has a 16-pin base. It was used at CRNL for measuring the light emitted by the thermoluminescent dosimeters (TLD) worn in personal radiation dosimeters by laboratory personnel. Under normal circumstances the TLDs, which are one part of the personal dosimeters, are read out routinely every two weeks and the recorded dose is entered into the worker’s record.
