MRA Appendix B

This page contains a collection of old key / supplementary comparison data. The content is not necessarily up-to-date anymore.

An officially maintained list of EURAMET TC-L comparisons with results can be found at the BIPM website.

CCL key comparisons (CCL-Kx)

First round of  Key Comparisons, authorised by the CCL.

CCL-K1Gauge blocksCompleteFinal report
CCL-K2Long gauge blocks/length barsCompleteFinal report
CCL-K3PolygonsCompleteFinal report
CCL-K4Ring & plug gaugesCompleteFinal report
CCL-K51D CMM artefactsCompleteFinal report
CCL-K62D CMM artefactsCompleteFinal report

Second round of  Key Comparisons, authorised by the CCL.
(Not all future comparisons follow the classical scheme, some are operated as inter-RMO comparisons).

CCL-K1.2009Gauge blocks up to 500 mmPlanning -


CCL NANO pilot studies (NANOx)

Official pilot studies using MRA guidelines, authorised by the CCL.

NANO1Photomask linewidthStarts soon -
NANO2 (CCL-S2)Step heightCompleteFinal report
NANO3 (CCL-S3)LinescalesCompleteFinal report
NANO4 (CCL-S1)1D gratingsCompleteFinal report
NANO5 (CCL-S4)2D gratingsCompleteFinal report
NANO6SPM linewidthStarts soon -


EURAMET key comparisons (EURAMET.L-Kx)

New key comparisons organized by EURAMET's TC Length and designed to link to corresponding CCL key comparisons.

NumberSubjectProject No.Status / Report
EUROMET.L-K1Gauge blocks471Final report
EUROMET.L-K1.1Gauge blocks634Final report
EUROMET.L-K1.2Gauge blocks1138Final report
EUROMET.L-K2Long gauge blocks602Final report
EURAMET.L-K1.2011Gauge blocks (up to 500 mm)1218Final report
EUROMET.L-K3.1Optical polygons870Final report
EUROMET.L-K3.2009Autocollimators1074Final report
EUROMET.L-K4.2005Ring & plug gauges812Final 1
Final 2
EUROMET.L-K5-20041D CMM artefacts777Final report
EUROMET.L-K62D CMM artefacts743Final report
EUROMET.L-K7.2006Linescales (up to 100 mm)882Final Report
(not approved)
EUROMET.L-K8Roughness1003Final report
EURAMET.L-K8.2013Key comparison on surface roughness standards1245Final report



EURAMET supplementary comparisons (EURAMET.L-Sx)

Previous and new comparisons organized and reviewed by EURAMET TC-Length as being suitable for supporting the MRA.

NumberSubjectProject No.Status / Report
EUROMET.L-S1Linescales252BNM/LNE, 1995
EUROMET.L-S2Thermal expansion of gauge blocks275Metrologia paper
Final report
EUROMET.L-S3Depth setting standards301Final report
EUROMET.L-S4Wires (diameter)308Final report
EUROMET.L-S5aRoundnessBCRFinal report
EUROMET.L-S5bRoundness361Final report
EUROMET.L-S6Thermal expansion of long gauge blocks390PTB report
EUROMET.L-S7Surface platesBCREUR 14059 EN, 1992
EUROMET.L-S8Nd YAG lasersBilateralFinal report
EUROMET.L-S9Grid platesBCR 34423442/1/0/189/91/7
EUROMET.L-S10Squares570Final report
EUROMET.L-S11Surface texture600Metrologia paper
Final report (6MB)
EUROMET.L-S12Gauge blocks by comparison601Final report
EUROMET.L-S13Cylindrical artefacts369Final report (PTB)
EUROMET.L-S14Steel tapes677Final report
EUROMET.L-S15Step height standards by SPM707Final report
EUROMET.L-S15aStep height standards by SPM925Final report
EUROMET.L-S16Gauge blocks by comparison797Final report
EUROMET.L-S17Steel tape, trilateral (link to S14)875Final report
EUROMET.L-S18Granite square, bilateral (link to S10)905Final report
EUROMET.L-S19Steel cylindrical square, bilateral (link to S10)910Final report
EURAMET.L-S20Laser distance measuring instruments1169Final report
EURAMET.L-S21Thread pitch1223Final report
EURAMET.L-S22Gauge blocks by comparator1254Final report
EURAMET.L-S23Roundness by multi-step1269Final report
EURAMET.L-S25Comparison of pocket-type laser distance measurement instruments1354Final report
EURAMET.L-S26Measurement of groove depth standard in the range μm up to 1 mm1407Final report



EURAMET/EUROMET bi-lateral comparisons

Bilateral comparisons, not necessarily registred to MRA KCDB.

NumberSubjectProject No.Status
NoneIndexing tables 725Final report



Previous EUROMET key comparisons (EUROMET.L-Kx.PREV)

Existing Comparisons in the same subjects as the CCL-Kx series, reviewed by EUROMET Length as being suitable for the interim MRA.

NumberSubjectProject No.Report
EUROMET.L-K1.PREVGauge blocks229Final report
EUROMET.L-K2.PREVLong gauge blocks/length bars254Final report
EUROMET.L-K3.PREVPolygons371Final report (PTB)
EUROMET.L-K4.PREVRing & plug gauges384Final report
EUROMET.L-K5.PREVStep gauge372Final report (PTB)