Data has to be delivered with additional information on which datum and coordinate system they are based upon. Helpful additional information is:

  • Description of location and coordinates on the chart/sketch
  • Location name, preferably as specified in the nautical chart
  • Chart number if nautical chart

At you can find useful information about charts, location names and positions in UTM coordinates.

Additional information can be found in "Efs nr. 1" and in the article «Miscellaneous Notices to Mariners».

Data should be provided in these formats:
Datum WGS84 EUREF89 Ed50  
Coordinate system Geographical N, E
(degrees minute and optionally
UTM, specify the zone NGO, specify the axis  
Format SOSI Shape Text file, xy(z)

Here you will find an overview with deadline dates for delivery of notices to mariners to the Efs, as well as date of issues.

It is of importance for safety at sea that the official nautical charts are quickly and continuously updated. This is especially true in connection with new constructions and modifications of installations at sea which may affect safe navigation.

Inadequate updates may cause damage to vessels and installations which can lead to compensation claims from third parties. The Norwegian Mapping Authority Hydrographic Service is not responsible for the lack of update-to-date information due to the owner not sending them sufficient information.

Questions about contribution and delivery of nautical information, or information about your case, can be sent on e-mail to, or call the Norwegian Mapping Authority on + 47 32 11 80 00.

Current messages

Deliveries of current messages are to be sent to

Current messages are for example:

  • Temporary (T) notices. When the notice is only valid for a specified time period.
  • Preliminary (P) notices. When the announcement relates to an activity or condition that will become permanent and result in a chart update.
  • Gunnery exercises and warnings (seismic, rig moves, pre-laying of anchors).
  • Miscellaneous. When the notice is not related to a specific chart, but contains information which can be of importance to navigators.

Messages about permanent changes

Deliveries of nautical information about permanent changes are to be sent to

These notices concern messages with information about permanent changes which are of significance to safety of life at sea, for example:

  • New underwater rocks/depths
  • New or alteration of lights
  • Changes to buoys and beacons
  • New or adjustments to submarine cables and pipelines
  • New or adjustments to overhead cables
  • Wreck or obstructions which can be an obstacle to fishing and shipping etc.

Messages can also be delivered by mail: The Norwegian Mapping Authority Hydrographic Service, Post-box 60, N-4001 Stavanger.

Contributors are required to follow up that the submitted nautical information has been published in the Norwegian NM Etterretninger for sjøfarende (Efs) / nautical charts as they intended.

Contributors of nautical information to the Efs

The main contributors of nautical information to the Norwegian NM, Etterretninger for sjøfarende (Efs), can be divided into three groups:

  1. Government agencies such as: The Norwegian Coastal Administration, The Norwegian Public Roads Administration, The Directorate of Fisheries, Port Authorities, and local municipalities. Typical data are lights and aids to navigation, bridges, fish farms, quays, fillings and moles, etc.
  2. Private entrepreneurs constructing new or making changes to existing infrastructure which may affect the safe navigation at sea. This includes new/modified quays, marinas, moles, marine farms, fillings, overhead cables, submarine cables, etc.
  3. Private companies making constructions at sea that are not relevant for safe navigation, but where the object can be damaged by anchoring or by fishing activity, such as submarine pipelines or oil-related equipment on the seabed in the North Sea.