International intercomparisons

Results of CCPR K3.a (luminous intensity and K4 (luminous flux)

These comparisons were conducted between 1997 and 1998. The figure below are recreations form the official report. The figures show the relative difference in measured luminous intensity (candela) and luminous flux (lumen). The error bars are the expanded uncertainties with a coverage factor, k=2, reported by each participant. A key for the acronyms of the participating laboratories are shown in this link.

Results of CCPR K1.a (spectral irradiance 250 nm to 2500 nm)

This comparison was conducted between 2000 and 2004. The figures below are extracts from the official report. The first figure shows the percent difference of measured spectral irradiance values (from the reference value) by each laboratory. The second figure shows the combined standard uncertainties reported by each laboratory. A key for the acronyms of the participating laboratories are shown in this link.

For further details of the results of these comparisons, see the BIPM Key Comparison Data Base*.

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