About 25 years ago, I first visited the Instrumentation Labs at Oak Ridge National Laboratories (ONRL) at the invitation of the late Bob Shepard. Bob was a pioneer in many areas of temperature measurement and at that time was the Chairman of ASTM Committee E20 on Temperature. He was also head of the lab at ORNL.
He introduced me to Johnson Noise Temperature (JNT) measurement and showed me a prototype device that they had developed at Oak Ridge to implement the method as an possible alternate means to verify the calibration in situ of thermocouples in a nuclear reactor environment.
While the method was very complex, Bob was convinced it would eventually become commercially viable, if for no other reason than it was a fundamental technology related to the Absolute Thermodynamic Temperature Scale (Kelvin Scale) and required no calibration.
Work has continued to this day at ORNL and elsewhere. More recently, the staff at the National Institute of Standards & Technology (NIST) Thermometry Group have been producing some remarkable results, prototype devices and a raft of technical papers on the subject.
First a description about this unique temperature measurement method that has been studied for more than 30 years.
(more…)
TEMPERATURES.COM, INC. publishes information about measurement devices and measurement on its websites. The sites have articles, directories and news to foster competent measurements & analysis in industry & science. Sites are free. Submissions by visitors are encouraged and reviewed. Sites as of August 2007 are: lehos tecHeadlines, measureNEWS, About Temperature Sensors, TempSensor Directories, TempSensorNEWS, Measurement Databases, (MeasurementBlog.com)MeasurementMedia.com and MeasurementDevices.com
“Remember, it is important for thermographers to take an annual vision exam. At a minimum it should include a Jaeger Eye Test, to see if you can read small print, as well as a color-blind test such as the widely accepted Ishihara Color Deficiency.
Entries (RSS)