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Final report on the CCPR Key Comparison CCPR-K3.2014 Luminous Intensity



C Cameron Miller, Yuqin Zong, Arnold Gaertner, Eric Cote, Joaquin Campos, Gael Obein, Peter Blattner, Reto Scafer, Liu Hui, Jiang Xiaomei, Errol Atkinson, Erik Thorvaldson, Kenichi Kinoshita, Rheinhardt Sieberhagen, Irma Rabe, Teresa Goodman, Barry Scott, Armin Sperling, Detlef Lindner, Boris KHlevnoy, Evgeniy Ivashin


The metrological equivalence of national measurement standards in the field of photometry and radiometry is determined by a set of key comparisons chosen and organized by the Consultative Committee of Photometry and Radiometry (CCPR) of the Comité international des poids et mesures (CIPM), working closely with the Regional Metrology Organisations (RMOs). In September 2009 the CCPR decided that a second round of the key comparison K3 Luminous Intensity be commenced. The National Research Council of Canada (NRC) was chosen to pilot this comparison. A total of 12 participants were selected from the three RMO group members: EURAMET&COOMET (6: IO-CSIC, LNE-CNAM, METAS, NPL, PTB, VNIIOFI), APMP&AFRIMETS (4: NMISA, NIM, NMIA, NMIJ), and SIM (2: NIST, NRC). The comparison was organized as a star comparison (NMI-Pilot-NMI) using incandescent standard lamps supplied by each NMI (National Metrology Institute) as the travelling comparison artifact. This report describes the comparison organization (Section 2), the measurement methods and uncertainties achieved at all the participants and at the pilot (Sections 3 and 4), and the method for analysis and the results of the comparison according to this method (Section 4). It includes a comparison of the results of this comparison with the 1999 first round key comparison (Section 5). Section 6 presents a summary of the comparison.


CCPR, Luminous Intensity, Photometry, Radiometry


Miller, C. , Zong, Y. , Gaertner, A. , Cote, E. , Campos, J. , Obein, G. , Blattner, P. , Scafer, R. , Hui, L. , Xiaomei, J. , Atkinson, E. , Thorvaldson, E. , Kinoshita, K. , Sieberhagen, R. , Rabe, I. , Goodman, T. , Scott, B. , Sperling, A. , Lindner, D. , Khlevnoy, B. and Ivashin, E. (2022), Final report on the CCPR Key Comparison CCPR-K3.2014 Luminous Intensity, Metrologia (Accessed March 21, 2023)
Created June 15, 2022, Updated November 29, 2022