The Danish Geodata Agency assesses incoming information and data from various sources and if it triggers updates to nautical chart products. If updates are required, a chart correction is issued for paper charts.
Additionally, depth data from hydrographic surveys conducted by the Danish Geodata Agency's Maritime Survey Unit or other entities is processed. Changes in depths and depth contours cannot be addressed through standard chart corrections. Therefore these changes will be reflected only when a new edition of the affected paper charts is published.
For the majority of chart corrections, Notices to Mariners (EfS) serve as the primary source. A smaller portion of chart corrections is based on information and data from stakeholders such as ports, contractors, cable owners and other entities.
If the required corrections to a chart are too extensive to be applied via standard chart corrections, a new edition of the chart will be published. When a new edition is published, the previous edition is withdrawn.
Upon publication, paper charts include all corrections up to and including the date indicated in the lower-left corner of the chart. When acquiring a paper chart, users should be aware that any corrections released after this specified date must be manually added to the chart.