Two new miniature metallic sealed-cells containing the triple point of water, WTP (273.16
K) and the triple point of mercury, HgTP (234.3156 K) have been constructed for the
realization of the International Temperature Scale of 1990 (ITS-90) at the National
Institute of Standards (NIS-Egypt). The new cells will provide facilities for the
calibration of Capsule-type Standard Platinum Resistance Thermometers (CSPRTs). The two
cells will complete a multi-cells compartment in order to calibrate CSPRTs in one single
experiment. The multi-cells compartment contains two other cells; the triple point of
argon (83.8058 K) and the triple point of oxygen (54.3584 K) that has been already
developed and characterized before [M.G. Ahmed, Y. Hermier, Development of an adiabatic
calorimeter in the range 54 K–273 K in frame of a scientific collaboration LNE-NIS, AIP
Conf. Proc. 1552, 153 (2013)]. The system can calibrate two CSPRTs at once.
The compartment is accommodated in an adiabatic calorimeter. With a special technique, the
calorimeter could go down to a temperature of 52 K using liquid nitrogen and special
pumping system.