Calibration of platinum resistance thermometers using an intercomparison scheme

The report describes a procedure for the calibration of capsule type platinum resistance thermometers, (PRT), using one or more standard platinum resistance thermometers (SPRT) in the temperature range of 0 - 35 C. These PRT were designed to be used in density work through hydrostatic weighing where SPRT cannot be used because of space and other limitations, but the procedure is thought to be generally useful in other applications as well. The schedule of intercomparisons was designed to eliminate possible trends in temperature variations of the constant temperature bath setup. Results of calibration can be expressed either in terms of the two constants alpha and delta, or in a table relating R(t)/R(O) to t sub 68 within the range of calibrations.