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Call for tenders : Vacuum FT-IR for gas analysis  
Deadline for receipt of replies: 30 April 2014.

CIPM meeting 2013  
The report of the CIPM's 102nd meeting is available on the BIPM webpage. The decisions from the meeting held in March 2014 are also available. – Click here

2013 Director's report now available  
The 2013 Director's Report is now available in English on the BIPM website. It is being translated into French and will be made available as soon as possible on the website. The final printed report will be distributed later in the year as a single pack including the minutes of the 2013 meeting of the CIPM and the Rapport Annuel in both French and English. – BIPM publications

Preparation for World Metrology Day  
The 2014 World Metrology Day poster, highlighting Measurements and the global energy challenge, is now available for download. – www.worldmetrologyday.org

New Member State: Iraq  
The BIPM is pleased to announce that the Republic of Iraq acceded to the Metre Convention on 20 August 2013, bringing the number of Member States to 56. – See the full list of Member States and Associates

Two-year secondment: Executive Secretary of the JCRB  
Note that formal applications should be made through the applicant's NMI Director. – Closing date for applications: 16 May 2014

New Associate of the CGPM: Luxembourg  
As of 29 January 2014, the Grand Duchy of Luxembourg is an Associate of the CGPM. – See the full list of Member States and Associates

Preliminary information about the 25th meeting of the General Conference on Weights and Measures  
Preliminary information about the 2014 meeting of the CGPM is now available on the BIPM website. Further details will be added shortly, after the March 2014 meeting of the CIPM.
Note: The CGPM is made up of delegates of the governments of the Member States with observers from the Associates of the CGPM. – CGPM website

The BIPM presents its best wishes for 2014  
Best wishes and season's greetings for a happy holiday and prosperous New Year from the Director and staff at the BIPM. – Happy New Year!

New edition of BIPM e-News  
Download the December 2013 issue

Draft Chapters 1, 2 and 3 of the 9th edition of the SI brochure are now available on the BIPM website  
This draft document is made available in order to encourage communication, awareness and debate on the possible revision of the SI. The document will continue to evolve over the coming years. – Draft dated 16 December 2013

Election of Dr Dae-Im Kang to the CIPM  
Dr Dae-Im Kang, President of KRISS (Republic of Korea) has been elected to the CIPM. – See the list of CIPM members

Retirement of Prof. Ian Mills and appointment of Prof. Joachim Ullrich as next President of the CCU  
At the meeting of the Consultative Committee for Units (CCU) in June 2013, Professor Ian Mills FRS, President of the CCU, announced his intention to resign with effect from the end of 2013. The delegates of the CCU gave him a standing ovation and warm thanks were expressed by Dr Barry Inglis, President of the CIPM, and Dr Terry Quinn, Emeritus Director of the BIPM, for the 17 years of service he has given to the CCU.
At their meeting in October 2013, the members of the CIPM also paid tribute to the extent and quality of Prof. Mills' service. They appointed Professor Joachim Ullrich, President of the PTB and a member of the CIPM, to serve as the next President of the CCU, with effect from 1 January 2014. Decisions of the CIPM (October 2013)

New signatory of the CIPM MRA: MASM (Mongolia)  
On behalf of MASM (Mongolian Agency for Standardization and Metrology), Galbadrakh GANTUMUR signed the CIPM MRA on 23 October 2013. – See the updated list of participants in the CIPM MRA

New Associate of the CGPM  
As of 7 August 2013, Mongolia is an Associate of the CGPM. – See the full list of Member States and Associates

Compendium of main rules and practices applicable to the BIPM  
We are pleased to announce that, as requested by the CIPM at its meeting in June 2013, the Compendium is now available on the BIPM website. – Click here

New edition of BIPM e-News  
Download the July 2013 issue and browse the 2012 Core Data

Official introduction of Rapid UTC  
The BIPM Time Department's pilot experiment on the computation of Rapid UTC (UTCr) has concluded successfully with the approval of the CCTF WG on TAI and its authorization to start official publication of UTCr from 1 July 2013.
The pilot experiment began in January 2012 with the objective of studying the feasibility of computing a weekly UTC solution to assist the contributing laboratories to better synchronize their local time scale realizations to UTC. Of the 72 laboratories participating in the computation of UTC, 39 contributed to the pilot experiment.
Results of UTCr are published at http://www.bipm.org/jsp/en/TimeFtp.jsp?TypePub=publication and at ftp://tai.bipm.org/UTCr/Results/.
Rapid UTC should be understood as intermediate results before the publication of BIPM Circular T, which remains the only means of getting traceability to UTC. – See UTCr results on the BIPM Time Department's ftp server

Impact Factor of Metrologia up again  
As released in the Thomson Reuters Journal Citation Reports®, the 2012 Impact Factor for Metrologia is 1.902. – Access Metrologia on-line

The University of York has awarded an Honorary Professorship to Dr Milton, Director of the BIPM  
The BIPM is pleased to announce that from 1 June 2013 Martin Milton is an Honorary Professor in the Department of Chemistry at the University of York (United Kingdom). Whilst working at NPL, Dr Milton collaborated with academics at the University of York to develop standards for long-term monitoring of atmospheric composition. – Director's Office

Monday 20 May is World Metrology Day  
This year's theme is "Measurements in Daily Life" – a wide-ranging topic that concerns everyone in a multitude of situations. We invite you to download the promotional poster and other material from the World Metrology Day website, and to browse the many events around the world being organized to celebrate the day. – www.worldmetrologyday.org

New signatory of the CIPM MRA: INM (Colombia)  
On behalf of INM (Instituto Nacional de Metrología de Colombia), Hernan Dario Alzate Sepulveda signed the CIPM MRA on 15 May 2013. – See the updated list of participants in the CIPM MRA

New members of the CIPM  
Following the retirements of Prof. Göbel, Dr Hengstberger and Dr Schwitz from the International Committee of Weights and Measures (CIPM), three new members have been elected: Prof. Humberto Brandi (Director for Scientific and Industrial Metrology, INMETRO, Brazil), Dr Wynand Louw (Director, Technical Infrastructure Development, NMISA, South Africa) and Prof. Joachim Ullrich (President, PTB, Germany). – See list of CIPM members

We are pleased to announce that articles can now be published in Metrologia on an open access basis  
To provide the greatest flexibility to authors the journal will now operate under a hybrid model, accepting both standard and open access submissions. – More on open access publishing

Metrology training courses aimed at assisting developing countries  
NMI- and RMO-run metrology training courses aimed specifically at assisting developing countries are now listed under the BIPM banner on the DCMAS Network website. Details of other such courses, including appropriate text, links and documents, should please be submitted by email for inclusion in the list.
Conferences, workshops and general assemblies will continue to be listed on the BIPM website. – BIPM page on the DCMAS Network website

Preparation for World Metrology Day  
The 2013 World Metrology Day poster, celebrating Measurements in daily life, is now available for download. – www.worldmetrologyday.org

New Member State: Colombia  
The BIPM is pleased to announce that the Republic of Colombia acceded to the BIPM on 6 February 2013, bringing the number of Member States to 55. – See the full list of Member States and Associates

UTCr's 1st birthday  
"Rapid UTC" (UTCr) is one year old already. The first results of the pilot experiment aimed at providing access to UTC on a shorter timescale than the monthly Circular T were published on 29 February 2012, and the BIPM Time Department has been publishing UTCr results on a weekly basis since then. One year into the pilot experiment, UTCr has reached the expected quality and official publication is expected to start in mid-2013. – Pilot experiment on "rapid UTC"

Circular T celebrates its 25th birthday  
The 300th issue of Circular T was published by the BIPM Time Department on 10 January 2013, after 25 years of uninterrupted monthly publication. – See the FTP server of the BIPM Time Department

The 13th Director of the BIPM  
The New Year 2013 marks the move of the directorship of the BIPM from Professor Michael Kühne to Dr Martin J.T. Milton. – Click here for more information

The BIPM presents its best wishes for 2013  
Happy New Year!

New issue of the BIPM e-News  
Download the December 2012 issue

World Metrology Day 2013  
The theme for World Metrology Day 2013 has been announced: Metrology in Daily Life. www.worldmetrologyday.org

Publication of JCGM 106:2012  
Document JCGM 106:2012 "Evaluation of measurement data – The role of measurement uncertainty in conformity assessment", produced by the JCGM Working Group on the Expression of Uncertainty in Measurement (JCGM-WG1), was approved by the JCGM Member Organizations in October 2012. It constitutes the fourth of the series of documents accompanying the GUM. – Download JCGM 106:2012

New signatory of the CIPM MRA: NSI (Namibia)  
On behalf of NSI (Namibian Standards Institution), Riundja Ali Kaakunga signed the CIPM MRA on 16 October 2012. – See the updated list of participants in the CIPM MRA

New signatory of the CIPM MRA: European Space Agency (ESA)  
On behalf of ESA (European Space Agency), Franco Ongaro signed the CIPM MRA on 8 October 2012. – See the updated list of participants in the CIPM MRA

New signatory of the CIPM MRA: NSCL (Syrian Arab Republic)  
On behalf of NSCL (National Standards Calibration Laboratory, Syrian Arab Republic), Souhaila Elias signed the CIPM MRA on 17 September 2012. – See the updated list of participants in the CIPM MRA

New Associate of the CGPM: Namibia  
As of 10 August 2012, the Republic of Namibia is an Associate of the CGPM. – See the full list of Member States and Associates

Hugh Preston-Thomas, 23 December 1923 - 11 August 2012  
It is with great sadness that the BIPM has learnt of the death of Hugh Preston-Thomas, Honorary Member of the CIPM. – Hugh Preston-Thomas

Secondment: Mr Chingis Kuanbayev  
Mr Chingis Kuanbayev, Head of the Mechanical and Geometrical Laboratory at the National Metrology Institute of Kazakhstan (KazInMetr RSE), will be on secondment at the BIPM from 1 October 2012 to 30 November 2014. – He will take over as JCRB Executive Secretary as from 3 December 2012.

New signatory of the CIPM MRA: BOBS (Botswana)  
On behalf of BOBS (Botswana Bureau of Standards), Masego MAROBELA signed the CIPM MRA on 26 July 2012. – See the updated list of participants in the CIPM MRA

Memorandum of Understanding between the BIPM and the IAEA  
The BIPM and the International Atomic Energy Agency (IAEA) signed a Memorandum of Understanding on 25 June 2012, formalizing more than 50 years of close working relations between the two organizations in the field of radiation measurements. – BIPM-IAEA MoU

New members of the CIPM  
Following the retirements of Dr Bennett, Prof. Issaev and Dr Tanaka from the International Committee of Weights and Measures (CIPM), three new members have been elected: Dr Brian Bowsher (Managing Director, NPL, United Kingdom), Dr Vladimir Krutikov (Rosstandart, Russian Federation) and Dr Takashi Usuda (Director of the International Metrology Cooperation Office, NMIJ/AIST, Japan). – See list of CIPM members

Next Director of the BIPM: Dr Martin Milton  
The BIPM is pleased to announce that Dr Martin Milton will join the BIPM on 1 October 2012 as Deputy Director/Director Designate to take over the directorship from the present Director, Dr Michael Kühne, on 1 January 2013.
Dr Milton received a BA in Physics from Oxford University in 1981 and a PhD in Physics from Southampton University in 1990 followed by a MBA from the London Business School in 1991. He joined the National Physical Laboratory of the UK in 1981 as a Scientific Officer, became Principal Research Scientist in 1994 and NPL Fellow in 1998. Since 2005 he is Lead Scientist for the Gas Metrology and Trace Analysis Group at the NPL. – Dr Martin J.T. Milton

New Director of the BIPM's Ionizing Radiation Department  
Mr José María Los Arcos, previously Research and Development Advisor at CIEMAT (Spain), has taken up his new post as Director of the BIPM's Ionizing Radiation Department. To facilitate a smooth transition from the previous Director of the Department, Dr Penelope Allisy-Roberts will continue in the role of BIPM Consultant until 31 August 2012. BIPM Ionizing Radiation Department

One second will be added to UTC at the end of 30 June 2012  
The IERS has announced that a leap second will be added to UTC on 30 June 2012 at 23 h 59 m 59 s UTC. Read more

Launch of BIPM e-News  
We are pleased to present the first issue of BIPM e-News, which now brings together into a single publication topics previously included in the BIPM Bulletin and the KCDB Newsletter. BIPM e-News will be published twice a year and will highlight some key recent issues and achievements. We hope that the readership of the former BIPM Bulletin and KCDB Newsletter will benefit from the comprehensive coverage provided by BIPM e-News, which will be circulated by email as well as being made available on the BIPM website. – Download the June 2012 issue

Survey: Your views on the BIPM and KCDB websites  
In preparation for the future revamping of the BIPM and KCDB websites, a questionnaire on the usability of our web applications has been drawn up. Feedback from our user community is an important driver for change and we would ask you please to participate by completing the survey available online at https://www.surveymonkey.com/s/BIPM-web-survey. The feedback provided will be taken into account in the development of our future web systems. – Deadline: 23 July 2012; this survey is now closed. Thank you for your input.

New Associate of the CGPM: Syria  
As of 31 May 2012, the Syrian Arab Republic is an Associate of the CGPM. – See the full list of Member States and Associates

New Associate of the CGPM: Botswana  
As of 30 May 2012, Botswana is an Associate of the CGPM. – See the full list of Member States and Associates

Estefanía de Mirandés appointed member of the CODATA TGFC  
We are delighted to announce that Dr Estefanía de Mirandés of the BIPM Mass Department has been appointed a member of the CODATA Task Group on Fundamental Constants (TGFC). The purpose of the CODATA TGFC is to periodically provide the scientific and technological communities with a self-consistent set of internationally recommended values of the basis constants and conversion factors of physics and chemistry based on all of the relevant data available at a given point in time. Established in 1969, the CODATA TGFC is one of the original Task Groups of CODATA. Because of the close linkage between the SI units and fundamental constants, the CODATA TGFC enjoys a close relationship with the Consultative Committee for Units (CCU) and the BIPM. – CODATA TGFC. See also: Towards the New SI...

David Burns' election to the ICRU  
We are delighted to announce that Dr David T. Burns FInstP of the BIPM's Ionizing Radiation Department has been elected a Commissioner of the International Commission on Radiation Units and Measurements (ICRU). The ICRU has the mission to develop and promulgate internationally accepted recommendations on radiation-related quantities and units, terminology, measurement procedures, and reference data for the safe and efficient application of ionizing radiation to medical diagnosis and therapy, radiation science and technology, and radiation protection of individuals and populations. David has been the BIPM observer on the ICRU for a number of years and has contributed to various of its report committees, and is also a member of the ICRU's only standing committee, which is on fundamental quantities and units. – See also: Dosimetry at the BIPM

Transit of Venus 2012  
In the 19th century the transit of Venus across the face of the Sun was used to calculate the astronomical unit, the distance between the Earth and the Sun. There is a chance to see this relatively rare event on 6 June 2012. After that, the next transit will occur in 2117! – Read more

New Associate of the CGPM: Oman  
As of 8 May 2012, Oman is an Associate of the CGPM. – See the full list of Member States and Associates

New Member State: Tunisia  
The BIPM is pleased to announce that the Republic of Tunisia, which has been an Associate of the CGPM since October 2007, acceded to the Metre Convention on 1 February 2012, bringing the number of Member States to 56. – See the full list of Member States and Associates

Publication of JCGM 200:2012  
This corrected version of the 3rd edition of the VIM cancels and replaces JCGM 200:2008. – International Vocabulary of Metrology – Basic and General Concepts and Associated Terms

International School of Physics "Enrico Fermi": Metrology and Physical Constants  
Applications for the Varenna Summer Schools are now open. Course CLXXXV – "Metrology and Physical Constants", co-directed by E. Bava (INRIM) and M. Kühne (BIPM) – will run from 17-27 July 2012. – Closing date for appications: 5 May 2012

PRESS RELEASE: ITU Radiocommunication Assembly defers decision to eliminate the leap second  
The ITU Radiocommunication Assembly has reached an important decision to defer the development of a continuous time standard in order to address the concerns of countries that use the current system of the leap second in Coordinated Universal Time (UTC).
The decision has been reached to ensure that all the technical options have been fully addressed in further studies related to the issue. These studies will involve further discussions within the ITU membership and with other organizations that have an interest in this matter and will be referred to the next Radiocommunication Assembly and World Radiocommunication Conference scheduled for 2015. – ITU Press Release, 19 January 2012

Special issue of Metrologia on Neutron Metrology  
This special issue completes Metrologia's trilogy on measurements in Ionizing Radiation, comprising issues on Radionuclide Metrology, Dosimetry, and Neutron Metrology. This essential reference provides a broad overview of neutron metrology, aiming to give both a clear introduction to the novice as well as an up-to-date description of the latest scientific developments for the more experienced reader.
Guest editors: David Thomas (NPL), Ralf Nolte (PTB) and Vincent Gressier (IRSN) – Browse Metrologia 48(6), December 2011

KCDB Newsletter  
Issue 16 (December 2011) is now available – Click here

PRESS RELEASE: UTC for the 21st Century  
The BIPM has issued a press release following the Royal Society Discussion Meeting on UTC for the 21st Century, which was held at the Kavli Royal Society International Centre, UK, on 3-4 November 2011. The meeting was organized by Dr Terry Quinn and Dr Felicitas Arias. – Click here for the full press release

PRESS RELEASE: The proposed redefinition of Coordinated Universal Time, UTC  
The International Bureau of Weights and Measures (BIPM) has issued the following press release to explain the proposed redefinition of Coordinated Universal Time, UTC. It sets out clearly the reasons for the change and what is involved. – Click here for the full press release

BIPM Bulletin  
News from Session II of the 100th meeting of the CIPM and the 24th meeting of the CGPM is now available – Click here

The BIPM, OIML, ILAC and ISO have issued a joint declaration on metrological traceability  
This declaration from the four internationally recognized bodies responsible for metrology, accreditation and standardization world-wide, addresses everyone for whom traceability is important. – 9 November 2011

Resolutions of the CGPM (2011)  
Resolutions adopted at the 24th meeting of the CGPM (17–21 October 2011) – See: Resolutions of the 24th meeting of the CGPM

PRESS RELEASE: CGPM approves possible changes to the SI, including redefinition of the kilogram  
The International Bureau of Weights and Measures (BIPM) has issued a press release following the unanimous vote by the General Conference on Weights and Measures (CGPM) to adopt Resolution 1: “On the possible future revision of the International System of Units, the SI”. – Click here for the full press release

New signatory of the CIPM MRA: BMM (Montenegro)  
On behalf of BMM (Bureau of Metrology), Vanja ASANOVIC signed the CIPM MRA on 19 October 2011. – See the updated list of participants in the CIPM MRA

Results of the first direct comparison of the quantum Hall effect in epitaxial graphene and gallium-arsenide have been published  
A future redefinition of the units for mass and current in terms of the Planck constant h and electron charge e, respectively, will depend on the accuracy of the relationships that provide a link between these constants and measurable macroscopic quantities. The quantum Hall effect (QHE) is an example of such a relationship, whereby the Hall resistance shows a series of quantized plateaux with values h/ie2, where i is an integer, independent of the material. The first direct comparison of the QHE in epitaxial graphene and gallium-arsenide was carried out jointly by the NPL (UK), the BIPM and researchers from Swedish and UK universities. The quantized resistance values were found to be identical in graphene and gallium-arsenide within the relative standard uncertainty of the measurement of 8.6 × 10−11 providing proof of the universality of the QHE in different materials. – Download the paper from New J. Phys., 2011, 13, 093026

Special issue of Metrologia on Modern Applications of Timescales  
This special issue of Metrologia reviews timescales in use today, including the internationally recognized references as well as some other scales adapted to specific applications. It discusses new and future developments and presents the - sometimes complex - procedures for making international recommendations.
Guest editors: E.F. Arias, W. Lewandowski (BIPM) – Browse Metrologia 48(4), August 2011

BIPM Bulletin  
News from the BIPM and session I of the 100th meeting of the CIPM is now available – Click here

New Associate of the CGPM: Montenegro  
As of 1 August 2011, Montenegro is an Associate of the CGPM. – See the full list of Member States and Associates

New signatory of the CIPM MRA: NPSL (Pakistan)  
On behalf of NPSL (National Physical and Standards Laboratory), Shaheen RAJA signed the CIPM MRA on 6 July 2011. – See the updated list of participants in the CIPM MRA

Announcement of the death of Pierre Giacomo  
It is with great sadness that the BIPM wishes to announce the death of Pierre Giacomo, Emeritus Director of the BIPM, on 29 June 2011.
Pierre Giacomo joined the BIPM as physicien chercheur principal on 1 November 1966. He was appointed by the CIPM as Deputy Director in October 1968, and as Director Designate on 30 September 1976. He took over from Dr Terrien as Director of the BIPM on 1 January 1978 and retired on 31 July 1988.
With the death of Pierre Giacomo we have lost a great metrologist. We will always keep him in our memory. – Pierre Giacomo

David Burns elected as Fellow of the Institute of Physics  
Dr David T. Burns, Principal Physicist at the BIPM, has been elected as a Fellow of the Institute of Physics in the UK, in recognition of his personal contribution to the advancement of physics. The BIPM is proud to announce this honour in acknowledgment of his scientific research, publications, international standing and supervision of the BIPM international dosimetry standards programme. – Dosimetry at the BIPM

Andrew Wallard awarded a CBE for services to international measurement  
Professor Andrew Wallard, Director Emeritus of the BIPM, was made a Commander of the Order of the British Empire (CBE) in the Queen's Birthday Honours 2011. The award is in recognition of Professor Wallard's services to international measurement. – Emeritus Directors

New signatory of the CIPM MRA: IMBIH (Bosnia and Herzegovina)  
On behalf of IMBIH (Institute of Metrology of Bosnia and Herzegovina), Zijad DZEMIC signed the CIPM MRA on 15 June 2011. – See the updated list of participants in the CIPM MRA

KCDB Newsletter  
Issue 15 (June 2011) is now available – Click here

New signatory of the CIPM MRA: SASO (Saudi Arabia)  
On behalf of SASO (Saudi Standards, Metrology and Quality Organization), Mr Nabil Ameen Molla signed the CIPM MRA on 25 May 2011. – See the updated list of participants in the CIPM MRA

New Associate of the CGPM: Bosnia and Herzegovina  
As of 24 May 2011, Bosnia and Herzegovina is an Associate of the CGPM. – See the full list of Member States and Associates

Dr Takashi Usuda has been awarded the Ichimura Prize in Technology  
Dr Takashi Usuda, a visiting scientist at the BIPM, was awarded this prestigious prize on 28 April 2011 by the New Technology Development Foundation, Japan, for his contribution to improvement of the National Metrology Standard of Vibration Measurement.
The award was in recognition of his work on development of a laser interferometer for vibration acceleration calibration. The laser interferometer enables high resolution and robust characteristics against vibration noise*. He also established the national calibration programme for vibration acceleration in Japan. His achievements improved the Japanese metrology standard of vibration measurement and ensured the traceability of vibration measurements in industry to the national standard.
*T. Usuda et al., Development of laser interferometer for a sine-approximation method, Proc. SPIE, Vol. 4827, p. 29-36 (2002) – Dr. Takashi Usuda

Special issue of Metrologia on International determination of the Avogadro constant  
This special issue of Metrologia collects papers about the results of an international research project aimed at the determination of the Avogadro constant, NA, by counting the atoms in a silicon crystal highly enriched with the isotope 28Si.
Guest editors: Enrico Massa and Arnold Nicolaus – Browse Metrologia 48(2), April 2011

New Member State: Saudi Arabia  
The BIPM is pleased to announce that the Kingdom of Saudi Arabia acceded to the BIPM on 11 February 2011, bringing the number of Member States to 55. – See the full list of Member States and Associates

New signatory of the CIPM MRA: BSTI (Bangladesh)  
On behalf of the BSTI (Bangladesh Standards and Testing Institution, Bangladesh), Mr A. K. Fazlul Ahad signed the CIPM MRA on 25 March 2011. – See the updated list of participants in the CIPM MRA

Biosciences and biotechnology final report  
The final report entitled 'Study of Measurement Service and Comparison Needs for an International Measurement Infrastructure for the Biosciences and Biotechnology: Input for the BIPM Work Programme' is now available. The final report can be downloaded from the BIPM website. –

New signatory of the CIPM MRA: MSB (Mauritius)  
On behalf of the Mauritius Standards Bureau (MSB), Mauritius, Mr Khemraj Ramful signed the CIPM MRA on 9 March 2011. – See the updated list of participants in the CIPM MRA

"New SI" web pages  
Draft Resolution A of the Convocation of the next meeting of the CGPM presents the intention of the CIPM to propose a possible future revision of the SI based on fixing the numerical values of four invariants of nature: the Planck constant, the elementary charge, the Boltzmann constant and the Avogadro constant.
In order to encourage communication, awareness and debate on this important possible change, the BIPM is pleased to present its new web pages dedicated to explaining the "New SI" and giving access to Draft Resolution A as well as to Draft Chapter 2 of the next edition of the SI Brochure. – See http://www.bipm.org/en/new_si/

New signatory of the CIPM MRA: ZABS (Zambia)  
On behalf of the Zambia Bureau of Standards (ZABS), Zambia, Mr Mataa Mukelabai signed the CIPM MRA on 3 February 2011. – See the updated list of participants in the CIPM MRA

New signatory of the CIPM MRA: NMI-SIRDC (Zimbabwe)  
On behalf of the NMI-SIRDC (Zimbabwe), Mr Matthew Ranganai signed the CIPM MRA on 14 January 2011. – See the updated list of participants in the CIPM MRA

The results of the "Avogadro project" have been published  
The International Avogadro Coordination project brings together several NMIs as well as the BIPM and the IRMM in a collaborative effort to determine the Avogadro constant – essentially by counting the number of atoms in a 28Si crystal of known mass. Alain Picard, Director of the BIPM's Mass Department, has primary responsibility for the required mass measurements. By virtue of its extraordinarily low uncertainty, the result just published for the Avogadro constant, NA = 6.022 140 78(18) x 1023  mol–1, will be an important input datum for a future redefinition of the kilogram. An even lower uncertainty is anticipated in the foreseeable future. – Download the paper from Phys. Rev. Lett., 2011, 106, 030801

Change of Director  
As of 1 January 2011, Prof. Michael Kühne is Director of the BIPM. On his retirement, Prof. Andrew Wallard becomes Director Emeritus. – Click here for more details