PCST Network

Public Communication of Science and Technology


The revision of the International System of Units and the challenge to communicate it
The Brazilian case

Aline de Oliveira CoelhoUniversity of Coimbra / Inmetro. Brazil


  • Carlos Fiolhais Coimbra University   Portugal
  • Claudia JurbergFiocruz   Brazil
  • D├ęcio Ruivo Martins Coimbra University   Portugal
The objective of this study is to present the review of the International System of Units (SI) and the promotion of its updates in Brazil, under the responsibility of the National Institute of Metrology, Quality and Technology (Inmetro). In times when relationships and media are increasingly virtual, it is opportune to analyze Inmetro's dissemination strategies focusing on direct communication using social networks, particularly Facebook.

In November 2018, Metrology (the science of measurement and its applications) took a historic step: the approval of the redefinition of four (out of seven) units of measurement on which it was based: kilogram (mass), ampere (electric current), kelvin (thermodynamic temperature) and mole (amount of substance). The revision is based on fundamental physical constants, considered stable and immutable, and using quantum phenomena as the basis for universal units of measurement.

This process required an unprecedented joint campaign to publicize these changes, coordinated by the International Bureau of Weights and Measures (BIPM) to 'translate' and disseminate the information of this transition and its effects to the public, composed mostly by citizen-consumers and industry representatives. Despite some obstacles such as the election period in Brazil, Inmetro's communication initiatives have proven to be efficient, which is demonstrated by expressive reactions, comments and shared posts. They were analyzed by quantitative methods (content analysis) in which a numerical value was assigned for each type of reaction, which generated value for each post and allowed them to be classified according to their repercussion. The results are presented by visual resources, such as infographics.

The author has not yet submitted a copy of the full paper.

Category: Visual presentation
Theme: Time