Comparison
Comparison close
Results

No graphs of equivalence are included in the KCDB for this comparison.

Comparison
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Results

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for April 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for May 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for June 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for July 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for August 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for September 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for October 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for November 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for December 2023

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for January 2024

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for February 2024

Degrees of equivalence Dk = [UTC - UTC (k)] and associated expanded uncertainty Uk for March 2024

Comparison
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CC comparison
Linked comparison
CCTF-K001.UTC
Metrology area, Sub-field Time and Frequency, Time
Description Calculation of the reference time scale UTC (Coordinated Universal Time)
Time of measurements 1977 -
Status Continuous, approved for equivalence
References

Guidelines for participation in the ongoing key comparison in time CCTF-K001.UTC

Metrologia 40 2003 pp. 184 - 188

Metrologia 56 2019 042001 (26 pp.)

Measurand [UTC - UTC(k)] in ns
UTC(k) is the local representation of UTC maintained by the laboratory k

Transfer device Time transfer between participants is carried out using Global Positioning System (GPS) and Two-Way Satellite Time and Frequency Transfer (TWSTFT)
Comparison type Key Comparison
Consultative Committee CCTF (Consultative Committee for Time and Frequency)
Conducted by CCTF (Consultative Committee for Time and Frequency)
Comments Most recent KCDB update: 16 MaY 2024

Values are available every 5 days on MJD's ending by "4" and "9" (MJD: Modified Julian Day).
They are published in the monthly Circular T and in the BIPM Time Section Annual Report.

The laboratories listed in the tab "Participants" are those which contributed to the Circular T. The RMO indicated is the RMO representing the National Metrology Institute of the state or economy.

At its 17th meeting in September 2006, the CCTF decided to assign the identifier "CCTF-K001.UTC" to this key comparison, first registered as "CCTF-K2001.UTC" in January 2005 (see page 28 of the Report of the 17th CCTF meeting).
This was implemented in the KCDB on 19 March 2007.

Additonal data for CCTF-K001.UTC: https://www.bipm.org/en/time-metrology gives access to successive issues of Circular T since No 125 (May 1998), and complete sets of values of [UTC - UTC(k)] since 1998.
Pilot institute BIPM
Bureau International des Poids et Mesures
BIPM - International Organization
Contact person Patrizia Tavella

+33 (0)1 45 07 70 76
First Name Last Name
wwww@ww.www +356719836 Institute 1 Institute 1 Khmelnitskiy
Pilot laboratory
BIPM

Bureau International des Poids et Mesures, BIPM - International Organization, N/A

BEV

Bundesamt für Eich- und Vermessungswesen, Austria, EURAMET

BFKH

Government Office of the Capital City Budapest, Hungary, EURAMET

BIM

Bulgarian Institute of Metrology, Bulgaria, EURAMET

BMM

Bureau of Metrology (Montenegro), Montenegro, EURAMET

BOM

Bureau of Metrology, Ministry of Economy (North Macedonia), North Macedonia, EURAMET

BelGIM

Belarussian State Institute for Metrology, Belarus, COOMET

CENAM

Centro Nacional de Metrologia, Mexico, SIM

CENAMEP AIP

Centro Nacional de Metrología de Panama AIP, Panama, SIM

DEF-NAT

Laboratoire de Métrologie de la Direction Générale des Transmissions et de l'Informatique, Tunisia, AFRIMETS

DFM

Danish Fundamental Metrology A/S, Denmark, EURAMET

DMDM

Directorate of Measures and Precious Metals, Serbia, EURAMET

DZM

State Office for Metrology, Croatia, EURAMET

registered under the acronym "IFZG" in Circular T

EIM

Hellenic Institute of Metrology, Greece, EURAMET

EMI

Emirates Metrology Institute, United Arab Emirates, GULFMET

ESA

European Space Agency - European Space Research and Technology Centre, European Union, EURAMET

FTMC

Center for Physical Sciences and Technology, Lithuania, EURAMET

GUM

Glowny Urzad Miar, Central Office of Measures, Poland, EURAMET

ILNAS

Bureau Luxembourgeois de Métrologie, Luxembourg, EURAMET

IMBIH

Institute of Metrology of Bosnia and Herzegovina, Bosnia and Herzegovina, EURAMET

INACAL

National Institute for Quality, Peru, SIM

INM

National Institute of Metrology, Romania, EURAMET

INM (CO)

Instituto Nacional de Metrología de Colombia, Colombia, SIM

INMETRO

Instituto Nacional de Metrologia, Qualidade e Tecnologia, Brazil, SIM

INPL

National Physical Laboratory of Israel, Israel, N/A

INRIM

Istituto Nazionale di Ricerca Metrologica, Italy, EURAMET

INTI

Instituto Nacional de Tecnologia Industrial, Argentina, SIM

IPE/ASCR

Institute of Photonics and Electronics, Czech Academy of Sciences, Czechia, EURAMET

IPQ

Instituto Portugues da Qualidade, Portugal, EURAMET

JV

Justervesenet, Norway, EURAMET

KEBS

Kenya Bureau of Standards, Kenya, AFRIMETS

KRISS

Korea Research Institute of Standards and Science, Korea, Republic of, APMP

KazStandard

Kazakhstan Institute of Standardization and Metrology, Kazakhstan, COOMET

LACOMET

Laboratorio Costarricense de Metrologia, Costa Rica, SIM

LNE-SYRTE

Observatoire de Paris/Systèmes de Référence Temps-Espace, France, EURAMET

MASM

Mongolian Agency for Standardization and Metrology, Mongolia, APMP

METAS

Federal Institute of Metrology, Switzerland, EURAMET

MIKES

VTT Technical Research Centre of Finland Ltd, Centre for Metrology/Mittatekniikan keskus, Finland, EURAMET

MIRS/SIQ/Metrology

MIRS/Slovenian Institute of Quality and Metrology/Metrology, Slovenia, EURAMET

MSL

Measurement Standards Laboratory, New Zealand, APMP

MUSSD

Department of Measurement Units, Standards and Services, Sri Lanka, APMP

registered under the acronym “SL” in Circular T

NICT

National Institute of Information and Communications Technology, Japan, APMP

NIM

National Institute of Metrology, China, APMP

NIMT

National Institute of Metrology (Thailand), Thailand, APMP

NIS

National Institute for Standards, Egypt, AFRIMETS

NIST

National Institute of Standards and Technology, United States, SIM

NMC, A*STAR

National Metrology Centre, Agency for Science, Technology and Research, Singapore, APMP

NMIA

National Measurement Institute, Australia, Australia, APMP

NMIJ AIST

National Metrology Institute of Japan, Japan, APMP

NMIM

National Metrology Institute of Malaysia, Malaysia, APMP

NMISA

National Metrology Institute of South Africa, South Africa, AFRIMETS

NPL

National Physical Laboratory, United Kingdom, EURAMET

NPLI

CSIR National Physical Laboratory of India, India, APMP

NRC

National Research Council, Canada, SIM

NSAI NML

NSAI National Metrology Laboratory, Ireland, EURAMET

NSC IM

National Scientific Centre "Institute of Metrology", Ukraine, EURAMET

ON/DSHO

Observatório Nacional/Serviço Nacional da Hora, Brazil, SIM

PTB

Physikalisch-Technische Bundesanstalt, Germany, EURAMET

RISE

Research Institutes of Sweden AB, Sweden, EURAMET

ROA

Real Instituto y Observatorio de la Armada, Spain, EURAMET

SASO-NMCC

National Measurement and Calibration Center - Saudi Standards, Metrology and Quality Organization, Saudi Arabia, GULFMET

registered under the acronym “SASO” in Circular T

SCL

Standards and Calibration Laboratory, Hong Kong, China, APMP

SMD

Service de la Métrologie Belge, Belgium, EURAMET

SMU

Slovensky Metrologicky Ustav, Slovakia, EURAMET

SNSU-BSN

National Measurement Standard - National Standardization Agency of Indonesia, Indonesia, APMP

registered under the acronym "IDN" in Circular T

TL

Telecommunication Laboratories, ChungHwa Telecom Co. Ltd., Chinese Taipei, APMP

UME

TÜBITAK Ulusal Metroloji Enstitüsü, Türkiye, EURAMET

UzNIM

Uzbek National Institute of Metrology, Uzbekistan, COOMET

VMI-STAMEQ

Viet Nam Metrology Institute, Directorate for Standards and Quality, Viet Nam, APMP

VNIIFTRI

Institute of Physical Technical and Radiotechnical Measurements, Rosstandart, Russian Federation, COOMET

VSL

VSL, Netherlands, EURAMET

Comparison
Comparison close
Results

The key comparison reference value of the key comparison CCTF-K001.UTC is UTC, as decided by the CCTF at its 15th meeting held in 2001.The degree of equivalence of each laboratory k with respect to the key comparison reference value is given by a pair of terms both expressed in ns:
Dk = [UTC - UTC (k)], where UTC (k) is the local representation of UTC maintained by laboratory k, and Uk, the expanded uncertainty (coverage factor equal to 2), of Dk.
 
The KCDB gives access to the degrees of equivalence for the last 12 months.

Uk = 2uk where uk is the combined standard uncertainty of [UTC - UTC (k)].
Uk does not include the prediction component due to the delay of publication of [UTC ‑ UTC (k)].
The uk values are valid for the whole month of calculation.

Comparison
Comparison close
Results

No Laboratory Individual Measurements are available from the KCDB for this comparison.