Electronic Charting Information

Electronic Charts, ECDIS and ECS Explained

For a comprehensive overview about electronic charts (ENC and RNC), electronic charting systems (ECDIS and ECS) and electronic chart carriage requirements under the International Convention on the Safety of Life at Sea (SOLAS), we recommend you read IHO publication S-66, Facts about Electronic Charts and Carriage Requirements, published in 2010:

This publication is written in an easy to read “question and answer” style and answers over twenty of the most commonly asked questions about electronic charts and their use in ECDIS and ECS. It contains the following information:

Section 1: An overview of electronic charting and regulations. This section explains what an ECDIS is, what an ECS is, what constitutes an ENC, what an RNC is, what ‘RCDS’ mode on an ECDIS is and explains chart carriage requirements under SOLAS regulations
Section 2: A list of contacts for detailed information on Flag State Implementation of ECDIS.
Section 3: ECDIS training objectives.
Section 4: Technical details about ENCs and RNCs. This section explains the benefits of ENCs over paper charts, explains what a ‘SENC’ is, what a ‘RENC’ is and explains the differences between official and private (non official) electronic chart data.
Section 5: Glossary/List of Abbreviations of electronic charting terms, references and relevant IMO Safety of Navigation Circulars.

Use of Electronic Charts in Australian Waters Explained

We recommend that you read the Facts about Electronic Charts and Carriage Requirements to become familiar with electronic charting terms and concepts prior to reading the following information.

What kinds of official electronic charts are available covering Australian waters?

Official charts are those issued by, or on the authority of, a Government authorised Hydrographic Office or other relevant government institution. The Australian Hydrographic Office (AHO) is Australia’s national charting authority. It is the only authority that can publish official paper and electronic charts of the Australian Charting Area.

The AHO publishes official electronic charts covering Australian, Australian Antarctic Territory, Papua New Guinea and Solomon Islands waters as Electronic Navigational Charts (ENC).

Which ENC services include coverage of Australian, Papua New Guinea and Solomon Islands waters?


The AHO distributes its ENC nationally under the ‘AusENC’ service. AusENC is sold in a range of packs at affordable prices with coverage tailored to domestic Australian operations. This service includes the full portfolio of published ENC covering Australian, Australian Antarctic Territory, Papua New Guinea and Solomon Island waters. For a full description of this service see the AusENC page on this website.

Other ENC services: The AHO has authorised international distribution of Australian-produced ENC via the IC-ENC distribution network and PRIMAR. These services are generally tailored to international commercial shipping by enabling ENC from multiple nations to be grouped together under a single subscription.   For more information on other ENC services, visit the IC-ENC (www.ic-enc.org) and PRIMAR (www.primar.org) websites.

Which RNC services include coverage of Australian, Papua New Guinea and Solomon Islands waters?

ARCs: The AHO has authorised the United Kingdom Hydrographic Office (UKHO) to distribute selected Australian paper nautical charts in both printed and raster form.   These do not include the full range of charts available from the AHO, particularly away from major commercial ports and shipping routes.    More information about the Admiralty Raster Chart Service (ARCS) can be found at the Admiralty website at www.admiralty.co.uk.

How will I recognise an official ENC of Australian waters?
Firstly, use of non official data in an IMO compliant ECDIS will result in a warning being displayed on the screen.   If the warning appears on screen, it is worth checking the coverage on screen for an area that looks different, as the area of unofficial data may not be in the immediate area surrounding your vessel.   A system with full ENC coverage for the depicted area will not display this warning.

All official ENC follow a standard naming convention using eight characters – a two letter national identifier, a single numerical ‘navigation purpose’ (scale band) identifier, then a five character file number.   National identifiers and the navigation purpose are controlled by the International Hydrographic Organization (IHO).

The AHO, as the national hydrographic authority for Australia, has been allocated the ENC national identifier code ‘AU’.

The AHO is the Primary Charting Authority for the National Maritime Safety Authority Papua New Guinea and the Solomon Islands Maritime Safety Administration. As Primary Charting Authority the AHO publishes ENC of Papua New Guinea waters with an ‘AU’ producer code and publishes ENC of Solomon Islands waters with an ‘SB’ producer code.

Publishing Nation
(always 2 letters)

Navigation Purpose Code
(no. in range
1 to 6)

Unique File Number
(always 5 characters)




How are AusENC kept up to date?


As part of subscribing to any AusENC pack, you will automatically receive a free, fortnightly, web-based update service for the duration of your subscription. Advice on how your subscribed pack has been affected by the latest round of updates will be forwarded by the AHO each fortnight to your registered email address.   You can then download either the latest cumulative update (recommended) or individual update from the AHO website.   If a new ENC, or new edition of an existing ENC, within your subscribed pack has been published, you will automatically be sent a new permit for that ENC covering the remainder of the subscription period.

Who are official electronic charts suitable for?

What are the electronic chart carriage rules and regulations in Australian waters?
SOLAS Vessels:
In Australian waters, the Australian Maritime Safety Authority sets the rules, under the Australian Navigation Act 2012, for vessels entering and operating within Australian waters. The Australian implementation of SOLAS regulations are set out in AMSA Marine Orders / Notices.

If you are a SOLAS mariner and want to find out about electronic chart carriage requirements in Australian waters you should consult the following Australian Maritime Safety Authority Marine Orders/Notices:

AusENC and RNC
In summary, AusENCs allow vessels navigating in Australian waters to meet chart carriage regulations under SOLAS Chapter V regulations (and AMSA) regulations provided they are kept up to date, used on an IMO compliant ECDIS with appropriate backup arrangements and the ECDIS is operated by appropriately trained and competent users.

RNC (ARCS) are not suitable for international SOLAS commercial vessels navigating in Australia to meet chart carriage regulations.

Australian Domestic Commercial Vessels:
Australian domestic commercial vessels are required to comply with the AMSA's National Standard for Commercial Vessels (NSCV).

AusENC and ARCS when kept up-to-date, will allow commercial vessels 12 metres or more in length and engaged in Australian domestic operations to meet the NSCV when used in an IMO compliant ECDIS or NSCV compliant ECS. However, it is good practice to carry appropriate nautical charts on vessels less than 12m in length when operating outside port and harbour limits.

For more information about carriage requirements, refer to NSCV Section B on area and vessel types and Part C, Subsection 7C regarding Navigation Equipment at: www.amsa.gov.au/vessels-operators/regulations-and-standards-vessels/national-standard-commercial-vessels.

Recreational Vessels:
In New South Wales, Northern Territory and South Australia it is a requirement to carry an official chart when going offshore or beyond smooth waters. In all other states it is recommended as good practice. AusENC and ARCS, when kept up-to-date, will allow recreational vessels to meet state electronic chart regulations. See the table below for further details:


Chart carriage requirements

Interstate Marine Authorities


Recommended for smooth, partially smooth and beyond smooth waters

Maritime Safety Queensland

New South Wales

Required for open waters

NSW Roads and Maritime Services


Advisable for all waters

Transport Safety Victoria

South Australia

Unprotected waters
All Vessels > 10 nautical miles from Shore

Department of Planning, Transport and Infrastructure


Advisable for all waters

Marine and Safety Tasmania

Northern Territory

For vessels > 5 metres


What are the system requirements to use AusENC?
AusENC are protected under the IHO S-63 data protection scheme. To use AusENC you will need a navigation system that is “IHO S-63 compatible”. For more information see AusENC System Requirements.

What are the system requirements to use ARCS?
ARCS are produced in encrypted HCRF format and require a navigation system that is ‘ARCS compatible’.

Where do I buy AusENC?
AusENC is commercially available through AusENC distribution agents.

However, Australian port authorities may request AusENC that cover their area of port limits or areas of operation, directly from the AHO as part of data sharing arrangements. For further information, please contact the AHO Licensing Manager:

P: (02) 4223 6500 F: (02) 4223 6599 E: hydro.licensing@defence.gov.au