177 
Process: 
3. Management of data and reference parame 
ters 
Name 
Date 
Created: 
Mathes 
28.5.98 
Data flow: 
Geographical data 
Checked: 
1. Origin 
• The origin of the stored geographical data must be known. 
2. Validity 
• It must be known whether the stored geographical data constitute certified data. This should be 
made available to processing procedures (particularly for voyage planning and execution). 
• In the case of electronic sea chart systems, the format of the geographical data used must 
follow international standards (e.g. S57). 
3. Quality 
4. Harmonisation 
• Any sea chart data represented must be harmonised with the ship’s currently navigated position. 
• With electronic sea chart systems, care must be taken to ensure that the sea region 
corresponding to the current ship position is constantly displayed. 
5. Criticality 
6. Limit values and alarm facilities 
7. Representation/display 
A summarised display of the geographical data available in the system must provided. This 
should likewise permit the selection of certain sea regions.