ENC safety and accuracy

November 24, 2017

Over the last couple of weeks you may have seen articles in press discussing the role of ENC and ECDIS in marine accidents like the one featured in Tradewinds on Friday 10 November.

We’d like to remind all our customers of the importance of CATZOC when planning and executing voyages using ENCs and ECDIS.

CATZOC (Category Zones of Confidence) is the ENC equivalent of the Source Data Diagram on a paper chart. CATZOC is used to indicate the accuracy of data presented on charts to assist mariners with determining a safe Under Keel Clearance.

Navigating officers should always:

  • Apply an appropriate level of appraisal and planning in preparation for the Intended voyage
  • Be fully aware of the ‘CATZOC’ quality of all areas of the intended voyage and apply suitable caution in areas where survey data is older.
  • Be fully aware of the ECDIS settings and use features like safety contours, shallow water contours, safety depth and deep water contours appropriately for prevailing situation.

You can read more about CATZOC here.