To assist WMO members operating the the WMO/GAW stations to link their sulphur hexafluoride observations to the WMO/GAW guideline and reference scale, WCC-SF6 implements audits and technical assistance for the stations.
Audits
The Audit consists of a System audit and Performance audit
A System audit is more generally defined as a check of the overall confirmity of a station with the principles of the GAW system. It is evaluated by a checklist*.
A Performance audit is a voluntary check for conformity of a measurement where the audit criteria are the data quality objective for the specific parameter. It is evaluated by the inter-comparison experiment with WCC-SF6's travelling standard gases**.
* Checklist? If you would like to see the checklist before having the audit, you can download here
* Travelling standard? This is a measurement standard, sometimes of special construction, intended for transport between different locations. For measurements of stable trace gases within WMO/GAW, this refers, in particular, to compressed gas cylinders (natural air or synthetic gas mixture) for use at different locations with an assigned mole fraction of one or more trace species resulting from calibration(s) by the CCL or from comparisons with laboratory standards by approved laboratory, such as the WCC.
Technical Assistance
Technical Assistance is when stations try to set up SF6 monitoring system and have difficulties, the WCC-SF6 supports its activities based on the WMO/GAW guidelines.
So far...
- 2015: Technical assistance to India
- 2016: Audits to the Cape Point station in South Africa