Comparison of Water Triple Point Cells
GUM, as the official signatory of the CIPM MRA, designated INTiBS for participation in the CIPM MRA in the low temperature range of the thermometry field. The water triple point temperature is the border between the low temperature range (covered by INTiBS) and the high temperature range (covered by GUM). GUM and INTiBS agreed that GUM provides the services at the water triple point related to the use of long-stem SPRTs (LSPRTs), while INTiBS provides the services at the water triple point related to the use of capsule-type SPRTs (CSPRTs). As consequence, only GUM took part in EURAMET.T-K7 of water triple point cells. This comparison (EURAMET.T-K2) was required by INTiBS to demonstrate its technical competence in calibrating CSPRTs at the triple point of water. The protocol of the comparison will follow closely the EUROMET.T-K7 protocol, with the only difference that INTiBS will use CSPRTs (instead of LSPRTs) in the local measurements.
Final Report 2013-04-03
The comparison has been completed and results are published in the KCDB.
The project was completed in November 2012. The bilateral equivalence between VSL and INTiBS was found to be satisfactory.