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JCGM Working Group on the Expression of Uncertainty in Measurement (GUM)

Working Group 1 (WG1) of the Joint Committee for Guides in Metrology (JCGM) has responsibility for maintaining the Guide to the Expression of Uncertainty in Measurement (GUM), which is now used worldwide at all levels of the measurement chain, from NMIs to industry.

An updated version of the GUM has been prepared under the name JCGM 100:2008 (GUM 1995 with minor corrections). In addition, the JCGM-WG1 has decided to produce a series of complementary documents to cover some topics of interest in more detail, whilst also directing them to groups of users with different levels of expertise. Please refer to the News from the JCGM-WG1 for information on the latest publications and the documents in preparation.


  • Dr Walter Bich [ISO]

Executive Secretary:


  • Dr Walter Bich  [ISO]
  • Prof. Maurice Cox  [BIPM]
  • Dr Charles D. Ehrlich  [OIML]
  • Dr Stephen Ellison  [IUPAC]
  • Dr Clemens Elster  [IUPAP]
  • Dr W. Tyler Estler  [BIPM]
  • Dr Nicolas Fischer  [IEC]
  • Dr Hidetaka Imai  [ILAC]
  • Dr Michael Krystek  [ISO]
  • Dr Juris Meija  [IUPAC]
  • Mr Luis Mussio  [OIML]
  • Dr Lars Nielsen  [BIPM]
  • Prof. Leslie R. Pendrill  [ILAC]
  • Dr Antonio Possolo  [IEC]
  • Prof. Nick M. Ridler  [IEC]
  • Mr Steve Sidney  [ILAC]
  • Dr Adriaan van der Veen  [ISO]
  • Prof. Graham H. White  [IFCC]
  • Corresponding Member: Dr Rüdiger Kessel [IUPAC]

Fundamental Reference Document (GUM):

Guide to the Expression of Uncertainty in Measurement

JCGM100:2008 – GUM 1995 with minor corrections. Published by the JCGM in the name of the BIPM, IEC, IFCC, ILAC, ISO, IUPAC, IUPAP, and OIML. It is now often referred to as the GUM 1995 with minor corrections.

The following citations are for information purposes but are not necessarily endorsed by the members of the JCGM-WG1. This compilation is not meant to be exhaustive.

General documents derived from the GUM

  JCGM: Upcoming meetings
3 December 2018: Meeting of the JCGM
4–7 December 2018: JCGM Working Group 1: GUM
24–28 June 2019: JCGM Working Group 2: VIM

JCGM summary
General information
JCGM Charter
Bibliography on Uncertainty
JCGM Working Group on the Expression of Uncertainty in Measurement (GUM)
JCGM Working Group on the International Vocabulary of Metrology (VIM)
Open documents
JCGM documents
JCGM-WG1 documents
"Annotated VIM3"
Rationale papers on VIM3
FAQs on the VIM3