Heat Standards Calibration in the DOE Complex*

As part of the Department of Energy (DOE) Non-nuclear Reconfiguration Program, the Office of Safeguards and Security Calorimetry Development Program has transferred from EG&G Mound Applied Technologies to the Los Alamos National Laboratory. An important function of this program is the calibration and certification of 238Pu heat standards, which are used to assure accountability of plutonium and tritium throughout the complex. To facilitate relatively uninterrupted calibration service, two calorimeters have been installed in the Los Alamos Plutonium Facility (TA-55). These calorimeters are capable of highly accurate measurements of heat standards with power ranging from 0.01 to 20 W. In addition, two new EG&G Mound Applied Technologies calibration calorimeters with a robot handling system have been installed in the Nuclear Safeguards Laboratories at Los Alamos National Laboratory. These calorimeters are located in a specially constructed laboratory that is controlled for temperature and humidity to achieve low uncertainty in the measurements. Because transportation of aging heat standards between sites within the DOE complex has become increasingly difficult, we are looking into several approaches to this problem. Repackaging of all heat standards to comply with Department of Transportation and American Nuclear Standards Institute requirements is a long-term goal.