Pilot Study: Comparing nitrous oxide gas standards – tackling a super climate pollutant by optical and reference material-based gas standards
Project Description
The United Nations Environment Programme’s “Global Nitrous Oxide Assessment” has identified N2O as a super pollutant accounting as the third important greenhouse gas species and as the major ozone-layer depleting substance. Throughout the UNEP’s N2O Assessment, metrological traceability of the super pollutant is not mentioned or yet asked for. However, two EURAMET members (NPL, VSL) have N2O CMCs published in the KCDB covering the range from 50 nmol/mol to 500 mmol/mol N2O. Globally, there are currently additional CCQM members with published CMCs on N2O plus the WMO institute NOAA.
For EURAMET and European paths of metrological traceability of nitrous oxide, we are proposing the development of new N2O gas standards with the focus on environmental and climate related target applications. Here, we explicitly hope to compare both optical N2O standards and reference material based N2O standards in the range from 0.3 to 3 µmol/mol.
To support N2O CMCs and related services, the key comparison CCQM-K68.2019 has been run in 2019-2020. The corresponding data is now entering the 5-years age. Furthermore, the CCQM-K68.2019 has followed the model 2 comparison scheme – with the focus of the preparation of gas standards. The last model 1 key comparison on N2O with the focus on the participants’ analytical capabilities dates even back to 2008. At that time, only one EURAMET member institute participated (VSL).
The aim of this comparison study is to evaluate the level of comparability of newly developed optical N2O standards and classical reference material-based N2O standards. The comparison protocol is yet to be designed.