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26 June 2017

S-57, S-63 and S-52: The latest IHO Standards and what they mean

Image of Mariner looking at ECDIS

​​​​​​​​​​​​​​​​​​​​​S-57, S-63 and S-52 are some of the important ECDIS and ENC Standards that have been developed by the International Hydrographic Organization (IHO) to support Safety of Life At Sea (SOLAS). Met by all charts in the ADMIRALTY Vector Chart Service​, these standards have been put into place to ensure that all Electronic Navigational Charts (ENCs) are accurate, secure and can be interpreted correctly by type-approved Electronic Chart Display and Information Systems (ECDIS).  Below, we outline what each of the standards mean and why they're so crucial to safety of ships at sea.

What is S-57?

S-57 is the data format used for the transfer of digital hydrographic data between national hydrographic offices and for ​its distribution to manufacturers, mariners and other data users.

Within this standard, the S-57 ENC product specification defines how hydrographic offices will construct an Electronic Navigational Chart. By meeting these specifications hydrographic offices will ensure that all electronic charts contain all the chart information that is necessary for safe navigation.

What is S-58?

S-58 sets out validation checks that must be performed on ENCs by hydrographic offices before they are released to the mariner at sea. These checks include tests to ensure that there are no irregularities in an ENC that could cause an ECDIS to malfunction. Irregularities could include incorrectly intersecting geometry, depths plotted on land or railway tracks appearing in open water.

​Tom Mellor - C​hairman of the IHO Electronic Navigational Chart Working Group (ENC WG)​ - explains what the IHO's ECDIS and ENC Standards mean​

What is S-63?

This standard covers three important areas:

  • Piracy Protection - to prevent unauthorised use of data by encrypting the ENC information.

  • Selective Access - to restrict access to ENC information to only those cells that a customer has been licenced for.

  • Authentication - to provide assurance that the ENC data has come from approved sources

For the mariner, this means that data which meets these standards is authenticated and comes from an official source, reducing the risk of using inaccurate data that is posed by unofficial ENCs and the risk of malware being introduced to a ship's IT systems.

What is S-52?

S-52 is a standard used by ECDIS manufacturers that determines how ENC data is displayed on an ECDIS screen through symbols, line styles, colours and other visual cues. This means that what the mariner sees on the screen is displayed in the same way across all approved makes and models of ECDIS.

The presentation library is an important part of this standard and ship owners are now expected to update to the latest library (4.0) by August 2017. You can find out more information on this change in our S-52 blog​.​​