Calibration of Gauge Blocks by Interferometry
This is an RMO Key Comparison on the measurement of short and long gauge blocks and will parallel the currently running CCL Key comparison (CCL-K1.2011). The measurements to be made are only the central length at 20 °C, measured both ways round. The technical procedure used for CCL-K1.2011 will also be followed for this comparison, though with some small modifications due to the fact that some EUROMET labs will only measure either the short or long gauge blocks. Moreover due to the large number of participants, the comparison must be performed in two concurrent loops. This has some influence on the key comparison reference value.
The artefacts used for this comparison (28 gauge blocks made of steel and ceramics, respectively) were newly purchased hence their history is unknown. Recurring stability measurement by the pilot are an important procedure in this comparison.
Final Report 2017-10-04
The comparison has been completed and results are published in the KCDB