INTRODUCTION 



The Naval Undersea Warfare Center (NUWC) 

 Temperature Calibration Facility was originally designed 

 for the calibration of deep-sea reversing thermometers/ 

 Since that time its function has been expanded to include 

 the calibration of other oceanographic research instruments 

 used in the measurement of temperature for Navy acoustic 

 studies. For example, such devices as the sensing ele- 

 ments of the NUWC Thermistor Chain/ which is now 

 employed in large-scale acquisition of data on the tempera- 

 ture structure of the upper layers of the sea, are routinely 

 calibrated in the tank. 



This report describes the improvements made to 

 the NUWC Temperature Calibration Facility during the last 

 10 years and provides a guide for the installation and use of 

 such a facility in the support of an oceanographic program. 

 It also presents the results of a deep-sea reversing 

 thermometer cross-calibration program in which the 

 facility was used (see Appendix). 



EQUIPMENT 



The present NUWC Temperature Calibration 

 Facility represents the result of a continued effort toward 

 improvement in reliability, accuracy, and accessibility. 

 Its principal components are a main calibration tank (fig. 

 1); tank lid (fig. 2); reading telescope (figs. 1 and 3); 

 thermal system (figs. 5 and 7); platinum thermometer 

 and temperature-control unit (figs. 4b and 6). 



'Navy Electronics Laboratory Report 784, A Temperature-Controlled Tank for 

 Calibrating Reversing Thermometers, by J. S. Black, 6 May 1957. 

 ^Navy Electronics Laboratory Report 1395, Vertical and Horizontal Thermal 

 Structures in the Sea, by E. C. LaFond and K. G. LaFond, 29 July 1966. 



