Revising the SI - news, updates and events

Event | 26 September 2018

In the lead up to World Metrology Day 2019 the MSL team will be delivering and partnering on several events to help communicate the importance and impact of the SI revision - we hope you can join us!

Event finder image

Register now for the following events:

Auckland SI Roadshow(external link) on Thursday 9 May

Wellington SI Roadshow(external link) on Monday 20 May

MSL is taking measurement to the regions with a series of free public events in our main centres for measurement testing laboratories, industry, innovators and the public.  We’ll share the latest information and impact the changes to the SI will have on businesses both here, and around the globe. We will also have some exciting speakers and displays that you should not miss.

Events will be held in partnership with the Metrology Society of Australasia, Dodd-Walls Centre and our Regional Business Partners. 

Download the Programmes:

Auckland [PDF, 189 KB]

Wellington [PDF, 191 KB]

Location Venue   Date Time
Auckland Unleash Space, Faculty of Engineering Building, Auckland University Register  Now(external link) Thursday 9 May 10:00 - 5:30pm
Wellington Callaghan Innovation, 69 Gracefield Road, Lower Hutt Register Now(external link) Monday 20 May 10:00 - 5.30pm

Enter the competition - We are running a competition for the duration of our Roadshows to see how far a Commonwealth Gold Medalist can throw our 1 kilogram standard.  Prizes are up for grabs so check out the video and competition details here.


International System of Units Redefinition, 2019

The International System of Units, known as the SI, is the globally-agreed basis for expressing measurements at all levels of precision, and in all areas of science, technology, and human endeavour.

The SI is presently made up of seven base quantities that each correspond to a universally-recognised unit.

The SI will undergo a major revision in May 2019 that will be implemented by the international measurement community. This global change involves moving away from material artefacts (e.g. the kilogram prototype in Paris), and instead employing a set of seven defining constants, from which all units can be derived.

The Measurement Standards Laboratory is the primary agency responsible for implementing the new SI definitions into New Zealand. Adopting the definitions will allow NZ to remain consistent with international best practice and allow precision measurement to be available to everyone.

Four of the base units – the kilogram, ampere, kelvin, and mole – will be redefined based on fixed numerical values of the Planck constant (h), the elementary charge (e), the Boltzmann constant (k), and the Avogadro constant (NA), respectively. The three remaining base units – the second, metre and candela – are already defined by physical constants, so it will only be necessary to edit their present definitions.

The SI has been revised several times since its formal adoption by the CGPM in 1960. However, redefining four base units at one time is unprecedented, requiring simultaneous world-wide collaborations in diverse fields of metrology. As in the past, care has been taken to ensure that there will be no perceptible impact on daily life and that measurements made with previous definitions of the units remain valid within their measurement uncertainties. Few users outside national metrology laboratories will notice the changes.

Why do we need the SI?

  • For fair domestic and international trade, so when you buy or sell a quantity of something you and your customers know what you are getting without being cheated or surprised.
  • So that things made in different places, countries, or even factories across the street will fit and work together.
  • To provide a common basis to communicate measurements in science, engineering, health, safety and the public good.

Want to know more?

You can download a handy factsheet on the changes here [PDF, 373 KB].

Read more about each of the measurement units here.

Read our case study 'Quantum Balancing Act for the SI'

Read 'Information for users about the revision of the SI' (external link)from the BIPM website.


Other Coming Events

15 - 17 April 2019 - New Zealand Institute of Physics Conference

Hosted at Canterbury University, this is your chance to dig deeper into the world of physics with workshops, demonstrations, posters and exciting Plenary speakers.  A number of MSL staff are presenting and the Kilogram to Kibble display is part of the exhibition. Find out more on the NZIP conference website(external link).

 20 May 2019 - World Metrology Day

World Metrology Day is an annual celebration to mark the signing of the Metre Convention on the 20th May 1875, which set the framework for global collaboration in the science of measurement. 

In May 2019, the historic change will take place, and we will finally see all the SI base units (International System of Units), such as the kilogram and the kelvin, referenced to a fundamental constant, as opposed to a physical artefact.

This is the final event of the regional roadshow. We will be celebrating World Metrology Day in Wellington on Monday 20th May with an exciting programme of events planned and announcing the winner of our Throwing the Kilogram competition.

20 - 26 May 2019 - Techweek19

This is New Zealand's annual festival of innovation with a theme of 'innovation that's good for the world'. Techweek18 was huge, with 540 events running in 24 locations across the country. Thousands of New Zealanders got involved in workshops, discussion and talks so expect more in 2019.  The programme for 2019 is being developed but keep an eye on the Techweek website(external link) for more information to come.

20 - 24 May 2019 - IEEE International Instrumentation & Measurement Technology Conference

The IEEE I2MTC is the flagship conference of the IEEE Instrumentation and Measurement Society, and is dedicated to advances in measurement methodologies, measurement systems, instrumentation, and sensors in all areas of science and technology. Hosted at the Grand Millennium Hotel in Auckland this is another conference where MSL staff will have a big presence running workshops, presentations and sponsoring International speaker Michael De Podesta from NPL in the UK. Find out more on the conference website(external link).