Dave Worton, Project Coordinator of the MetNO2 project, chaired a scientific session at the European Geosciences Union (EGU) General Assembly in Vienna, Austria for the third consecutive year.

This annually-convened conference is one of the largest of its kind in Europe, with 16,273 participants from 113 countries in 2019.

The session was part of the Atmospheric Sciences Program and was entitled ‘Atmospheric gases and particles: metrology, quality controlled and measurement comparability’. The session was organised as a collaboration between NPL (Dave Worton, Paul Brewer, Paul Quincey), METAS (Celine Pascale) and the BIPM (Joele Viallon), and provided an excellent forum for the dissemination of outputs from four EMPIR funded projects (16ENV02 Black Carbon, 16ENV05 MetNO2, 16ENV06 SIRS and 16ENV07 AEROMET) to the wider user community. The session was highly successful, with 23 presentations, seven oral and 16 posters, and more than 60 attendees.