This document is the EGO quality control manual for CTD (Conductivity, Temperature, Depth) and BGC (BioGeoChemical) data. It describes two levels of quality control.

• The first level is the real-time system that performs a set of agreed automatic checks. Adjustment in real-time can also be performed and the real-time system can evaluate quality flags for adjusted fields.
• The second level is the delayed-mode quality control system.

Please note that at the present time, official quality control procedures don’t exist for all BGC parameters. This document will be updated as soon as other procedures are available.