S-57 Edition 3.1 Encoding Bulletins: S-57 is the IHO standard for the exchange of digital hydrographic data. It has been used almost exclusively for encoding Electronic Navigational Charts (ENCs). However there is a need for S-57 to support additional requirements, which has prompted the IHO to develop the S-100 (IHO Universal Hydrographic Data Model) which will eventually supersede S-57. It is anticipated however that S-57 Edition 3.1 will continue to be used to produce ENCs for the foreseeable future.

S-57 Edition 3.1 has been frozen, and order to promulgate IHO approved changes the concept of  "Encoding Bulletins" was developed to communicate how data producers may modify their encoding practices to address those issues that affect the use of ENC data in ECDIS. Each Bulletin explains a particular ENC/ECDIS issue; recommended procedures for addressing the issue; and the consequences of not following the recommended procedures. It should be noted that the procedures described in these Bulletins are not compulsory; however it is strongly recommended that data producers follow them wherever possible to ensure the consistency of ENC production worldwide.

In 2010, the IHO approved the “unfreezing” of S-57 Appendix B.1, Annex A – Use of the Object Catalogue for ENC (UOC). This was done in order to transfer new and revised ENC encoding guidance incorporated in these Encoding Bulletins, and in other IHO publications, into the authoritative IHO ENC encoding guidance document. Encoding Bulletins that have been transferred into the UOC will maintain their reference in the Encoding Bulletins list, and the guidance included in each Bulletin will be replaced with the appropriate UOC clause references. Future new or revised ENC encoding guidance will be added as new Encoding Bulletins, which will subsequently be incorporated in future New Editions of the UOC as required.

These Bulletins have resulted from proposals brought to the attention of the ENC Maintenance Working Group (ENCWG). New bulletins must be approved by the ENCWG.

INDEX

ENC Product Specification (ENC PS), including Use of the Object Catalogue (UOC)

1. UOC clause 10.1.1 Navigational lines and recommended tracks; 10.2.2 Deep Water Route Centrelines; and 10.2.4 Recommended Routes [Updated – Feb 2012]
1.a UOC Clause 10.1.1 Navigational lines (NAVLNE) and recommended tracks (RECTRC) SUPERSEDED
1.b UOC Clause 10.2.2.2 Deep Water Route Centerlines (DWRTCL) SUPERSEDED
1.c UOC Clause 10.2.4 Recommended Route Centerline (RCRTCL) SUPERSEDED
2. UOC Clause 6.2.1 - Wrecks SUPERSEDED
3. UOC Clause 6.2.2 – Obstructions and foul areas SUPERSEDED
4. UOC Clause 4.8.5 – Dams (DAMCON)
5. UOC Clause 11.9.1 - Fishing facilities (FSHFAC)
6. UOC table 6.2 Wrecks
7. UOC table 6.3 Obstructions
8. UOC Clause 6.6 Caution areas [Updated – October 2011]
 9. UOC Clause 12.8.6.5 Directional lights (LIGHTS) [Feb 2007]
10. UOC Clauses 4.6.6.2 Floating Docks (FLODOC) [Feb 2007]
11. UOC Clauses 4.6.7.3 Pontoons (PONTON) [Feb 2007]
12. UOC Clause 4.1 Land Area (LNDARE) [Feb 2007]
13. UOC Clause 4.8.14 Built-up areas (BUAARE) SUPERSEDED
14. UOC Clause 12.1.2 Relationships [Feb 2007]
15. UOC Clause 11.2 Maritime jurisdiction areas [Jan 2008]
16. UOC Clause 11.2 Maritime jurisdiction areas: Disputed claims [Jan 2008]
17. Automatic Identification System (AIS) in ENC [Updated – October 2011]
18. ENC PS Clause 2.2 Cells: 180º Meridian of Longitude [Jan 2008]
19. UOC Clause 12.4.1 Buoys: Emergency Wreck Marking Buoy [Jan 2008]
20. ENC PS Clause 5.6 File naming: Use of _ (underscore) [Jan 2008]
21. External text files in national language [Jan 2008]
22. ENC PS Clause 5.4.1 Content of the exchange set [April 2008]
23. UOC Clause 5.4.1 Geo object depth areas [December 2008]
24. UOC Clause 2.1.5.1 Seasonal objects and Clause 2.6.1 Issuing updates in advance [Updated - March 2012]
25. UOC Clause 10.2.1 Traffic separation schemes [Updated - May 2010]
26. UOC Clause 12.8.6.1 Sector lights [April 2009]
27. UOC Clause 5.3 Soundings [April 2009]
28. ENC PS Clause 3.5.7 New attribute values in Edition 3.1 [June 2009]
29. ENC PS Clause 3.3 Objects permitted for use in ENC and their geometric primitives [Updated - May 2010]
30. UOC Clause 12.8.7 Various special types of lights [June 2009]
31. ENC PS Clause 5.7 Updating and UOC Clause 2.6 Updating [June 2009]
32. UOC Clause 6.2.1 Wrecks [June 2009]
33. ENC Product Specification Clause 3.1 Feature Object Identifiers [May 2010]
34. UOC Clause 12.1.2 Relationships [Updated – October 2011]
35. UOC Clause 6.2.2 Obstructions, foul areas and foul ground [October 2011]
36. UOC Clause 11.7.4 Offshore production areas [October 2011]
37. UOC Clause 1.1.1 References within S-57 to other IHO publications [October 2011]
38. UOC Clause 5.5 Dredged areas [October 2011]
39. UOC Clause 6.6 Caution areas [October 2011]
40. UOC Clauses 10.2.2.1 Deep water route parts; 10.2.3 Traffic separation scheme systems; and 10.2.6 Two-way routes [October 2011]
41. UOC Clause 15 Collection objects [October 2011]
42. UOC Clause 9.2.1 Anchorage Areas [May 2012]
43. UOC Clauses 6.1.2 Rocks which may cover; 6.2.1 Wrecks; and 6.2.2 Obstructions, foul areas and foul ground [May 2012]
44. UOC Clause 3.1.1 Magnetic variation [May 2012]
45. UOC Clause 5.8 Areas with inadequate depth information [May 2012]
46. UOC Section 2 Cartographic framework [May 2012]
47. UOC Clause 4.7.11 Vegetation [May 2012]
48. UOC Clause 2.8.1 Wide blank area [May 2012]
49. UOC Clause 2.3 Textual information [August 2012]
50. UOC clause 4.8.20 Views and sketches, viewpoints [August 2012]
51. UOC section 4 Topography [August 2012]
52. UOC clause 2.7 Multiple objects [August 2012]
53. UOC Clause 12.8.1 Description of lights [October 2012]
54. UOC Clause 12.14.1 AIS equipped aids to navigation [May 2013 - amended February 2015]
55. UOC Clause 12.4.1.1 Emergency wreck marking buoys [May 2013 - amended February 2015]
56. UOC Clause 2.1.5.1 Seasonal Objects [February 2015]
57. UOC Clause 2.8.1 Wide blank areas [February 2015]
59. UOC Clause 12.1.2 Relationships - Lights [March 2016]
60. UOC Clause 2.1.8 Seamless ENC coverage [March 2016]
61. UOC Clause 4.8.14 Built-up areas [April 2016]
62. Maintenance Document 8 revision to 1.Co.10 [amended - February 2015]
63. UOC Clause 2.2.3.1 Quality of bathymetric data [October 2019]
64. UOC Clause 2.6 Updating [September 2021]
65. Duplicate RCNM_RCID Combinations [February 2023]
66. Objects with 7 or more values populated for attribute RESTRN [July 2023]

Use of the Object Catalogue - Appendix B.1, Annex A - Encoding Bulletins (EB)

UOC Clauses 10.1.1 Navigational lines and recommended tracks; 10.2.2.2 Deep water route centrelines; and 10.2.4 Recommended routes

Please note this Encoding Bulletin SUPERSEDES EB1a, EB1b and EB1c below.

Revised encoding guidance regarding the resultant direction of line geometry for one way recommended tracks, deep water route centrelines and recommended route centrelines has been included in UOC Edition 3.1.0 (October 2012) – Clauses 10.1.1, 10.2.2.2 and 10.2.4.

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 EB1a - UOC Clause 10.1.1 Navigational lines (NAVLNE) and recommended tracks (RECTRC)

Please note that item EB1a, EB1b and EB1c have been SUPERSEDED by EB1 above

The third bullet point of clause 10.1.1 of Edition 2.1 (April 2002) of the Use of the Object Catalogue (S-57 Appendix B1, Annex A) states: "When the traffic flow is one way, the direction of digitising of an object of type line should be the same as the direction of the traffic flow".

The use of the word 'should' in this sentence means that the advice is only recommended and not mandatory. However, if this rule is not followed and navigation lines and recommended tracks are digitised in the opposite direction, the direction arrows shown on ECDIS displays will show the direction of traffic flow incorrectly.

Encoders are strongly advised, therefore, to follow this rule and digitise such lines in the direction of the traffic flow thereby avoiding possible ECDIS display problems.

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EB1b - UOC Clause 10.2.2.2 Deep Water Route Centerline (DWRTCL)

As per 1.a above, the first remark, in clause 10.2.2.2 needs to have its obligation changed from "should" to "must" i.e. "When the traffic flow is one way (attribute TRAFIC = 3), the direction of digitising should must be the same as the direction of traffic flow, thereby avoiding possible ECDIS display problems."

This is required as the S-52 Presentation Library (Edition 3.3) actually calculates the bearing of the digitised line and displays the bearing text based on this calculation. (The PL does NOT use the attribute ORIENT to display this text).

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EB1c - UOC Clause 10.2.4 Recommended Route Centerline (RCRTCL)

As per 1.a above the first remark, in clause 10.2.4 needs to have it's obligation changed from "should" to "must" i.e. "When the traffic flow is one way (attribute TRAFIC = 3), the direction of digitising should must be the same as the direction of traffic flow, thereby avoiding possible ECDIS display problems."

This is required as the S-52 Presentation Library (Edition 3.3) actually calculates the bearing of the digitised line and displays the bearing text based on this calculation. (The PL does NOT use the attribute ORIENT to display this text).

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EB2 -UOC Clause 6.2.1 - Wrecks

Please note that this item has been SUPERSEDED as the result of changes made to the Conditional Symbology Procedure for displaying this object class in ECDIS.

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EB3 - UOC Clause 6.2.2 – Obstructions and foul areas

Please note that this item has been SUPERSEDED as the result of changes made to the Conditional Symbology Procedure for displaying this object class in ECDIS.

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EB4 - UOC Clause 4.8.5 – Dams (DAMCON)

Revised encoding guidance regarding a dam that has its seaward edge coincident with the coastline was included in UOC Edition 3.0.0 (October 2011) – Clause 4.8.5.

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EB5 - UOC Clause 11.9.1 - Fishing facilities

New encoding guidance regarding fishing facilities located in deep water was included in UOC Edition 3.0.0 (October 2011) – Clause 11.9,1.

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EB6 - UOC table 6.2 Wrecks

Revised encoding guidance regarding the population of the attribute QUASOU on WRECKS objects was included in UOC Edition 3.0.0 (October 2011) – Clause 6.2.1.</p>

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EB7 - UOC table 6.3 Obstructions

Revised encoding guidance regarding the population of the attribute QUASOU on OBSTRN objects was included in UOC Edition 3.0.0 (October 2011) – Clause 6.2.2.

EB8 - UOC Clause 6.6 Caution areas

New encoding guidance regarding lines demarcating collision regulation areas was included in UOC Edition 3.0.0 (October 2011) – Clause 11.13.5.

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EB9 - UOC Clause 12.8.6.5 Directional lights (LIGHTS)

Revised encoding guidance regarding the orientation of directional and moiré effect lights was included in UOC Edition 3.0.0 (October 2011) – Clauses 12.8.6.5 and 12.8.6.6.

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EB10 - UOC Clauses 4.6.6.2 Floating Docks (FLODOC)

Revised encoding guidance regarding temporal attribution for floating docks was included in UOC Edition 3.0.0 (October 2011) – Clause 4.6.2.2.

EB11 - UOC Clauses 4.6.7.3 Pontoons (PONTON)

Revised encoding guidance regarding temporal attribution for pontoons was included in UOC Edition 3.0.0 (October 2011) – Clause 4.6.7.3.

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EB12 - UOC Clause 4.1 Land Area (LNDARE)

Revised encoding guidance regarding portrayal of names for land areas was included in UOC Edition 3.0.0 (October 2011) – Clause 4.7.1.

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EB13 - UOC Clause 4.8.14 Built-up areas (BUAARE)

Please note that this item has been SUPERSEDED as the result of changes made to the IHO Presentation Library Look-Up Tables for displaying this object class in ECDIS.

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EB14 - UOC Clause 12.1.2 Relationships

Revised encoding guidance regarding the role of the object class DAYMAR in a master to slave relationship was included in UOC Edition 3.0.0 (October 2011) – Clause 12.1.2.

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EB15 - UOC Clause 11.2 Maritime jurisdiction areas

New guidance regarding the encoding of “linear” maritime jurisdiction areas was included in UOC Edition 3.0.0 (October 2011) – Clause 11.2.

EB16 - UOC Clause 11.2 Maritime jurisdiction areas: Disputed claims

New guidance regarding the encoding of overlapping Territorial Sea and Exclusive Economic Zone areas due to the areas being in dispute between two or more Coastal States was included in UOC Edition 3.0.0 (October 2011) – Clause 11.2.4.

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EB 17 - Automatic Identification System (AIS) in ENC

New guidance regarding the encoding of AIS used as aids to navigation was included in UOC Edition 3.0.0 (October 2011) – Clause 12.14.1.

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EB18 - ENC PS Clause 2.2 Cells: 180º Meridian of Longitude

New guidance regarding the production of ENC cells that may span the 180° Meridian of Longitude was included in UOC Edition 3.0.0 (October 2011) – Clause 2.1.8.2.

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EB19 - UOC Clause 12.4.1 Buoys: Emergency Wreck Marking Buoy

New guidance regarding the encoding of IALA emergency wreck marking buoys was included in UOC Edition 3.0.0 (October 2011) – Clause 12.4.1.1.

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EB20 - ENC PS Clause 5.6 File naming: Use of _ (underscore)

Clause 5.6 of edition 2.0 (November 2000) of the ENC Product Specification (S-57 Appendix B.1) is not prescriptive as to the characters allowed for ENC data set file naming, resulting in some ECDIS rejecting ENC files containing the _ (underscore) character in the file name. The S-57 Maintenance Document MD8 (March 2002) lists both a Clarification (1.Cl.37) and a Correction (1.Co.32) explaining the allowable character format to be as described in ISO 9660, level 1. The existence of both a Clarification and a Correction in MD8 has resulted in confusion as to whether the _ (underscore) character is allowable in S-57 Edition 3.1 file names.

Encoders should note, therefore, that ENC data set file names must be composed from the upper case alphanumeric characters A to Z and the digits 0 to 9 only. The use of any other character, such as _ (underscore) is prohibited.

[Jan 2008]

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EB21 - External text files in national language

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EB22 - ENC PS Clause 5.4.1 Content of the exchange set

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EB23 - UOC Clause 5.4.1 Geo object depth areas

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EB24 - UOC Clause 2.1.5.1 Seasonal objects and Clause 2.6.1 Issuing updates in advance

NOTE: The guidance included in this Encoding Bulletin applies only when it is required to indicate seasonality, or to issue update information in advance, and the temporal attributes introduced for some navigational aid equipment objects in S-57 Supplement No. 2 are not available on the ENC production system used by the Producing Authority.

Clause 2.1.5.1 of Edition 2.1 (April 2002) of the Use of the Object Catalogue for ENC (S-57 Appendix B.1, Annex A) provides guidance on the use of the attributes PEREND and PERSTA for the encoding of seasonal objects in ENC. Clause 2.6.1 of the Use of the Object Catalogue for ENC provides guidance on the provision of advance update information, including the use of the attributes DATEND and DATSTA.

New tests introduced in Edition 3 (2008) of International Electrotechnical Commission document IEC 61174 - Marine Navigation and Radio communication Equipment and Systems – Electronic Chart Display and Information Systems (ECDIS) – Operational Performance Requirements, Methods of Testing and Required Test Results, have resulted in the implementation of the use of these time varying attributes by ECDIS manufacturers in their ECDIS systems.

S-57 Appendix A, Chapter 1 – IHO Object Catalogue (November 2000) contains the list of allowable attributes for S-57 Object Classes. For some navigational aid equipment objects the following time varying attributes are not included in the allowable list: 

FOGSIG – PEREND, PERSTA;

RADSTA – PEREND, PERSTA;

RETRFL – DATEND, DATSTA, PEREND, PERSTA;

RTPBCN – PEREND, PERSTA;

TOPMAR – DATEND, DATSTA, PEREND, PERSTA.

Encoders are therefore advised that where a seasonal or periodic navigation aid contains at least one of the equipment objects FOGSIG, RADSTA, RETRFL, RTPBCN or TOPMAR, the time varying attributes PEREND and PERSTA should not be populated for any object comprising the navigation aid. To indicate seasonality for such navigation aids to the mariner, the attributes STATUS = 5 (periodic/intermittent) and INFORM containing details of the period should be populated.

Where a navigation aid contains one of the equipment objects RETRFL or TOPMAR, advance update information should not be issued. Therefore the attributes DATSTA or DATEND should not be populated for any object comprising the navigation aid. An update applying the temporal change to the navigation aid should be issued as close as possible to the date of the change.

Alternatively, if time varying attributes DATSTA and/or DATEND have been populated for components of a navigation aid that contains at least one of the equipment objects RETRFL or TOPMAR, a separate update applying the temporal change to these equipment objects should be issued as close as possible to the date of the change.

[Updated - March 2012]

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EB25 - UOC Clause 10.2.1 Traffic separation schemes

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EB26 - UOC Clause 12.8.6.1 Sector lights

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EB27 - UOC Clause 5.3 Soundings

Revised encoding guidance regarding the population of the attribute EXPSOU on SOUNDG objects was included in UOC Edition 3.0.0 (October 2011) – Clauses 5.3 and 5.5.

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EB28 - ENC PS Clause 3.5.7 New attribute values in Edition 3.1

Revised encoding guidance regarding the population of the attribute INFORM to describe the meaning for attribute values which appeared for the first time in S-57 Edition 3.1 was included in UOC Edition 3.0.0 (October 2011) – Clause 1.1.

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EB29 - ENC PS Clause 3.3 Objects permitted for use in ENC and their geometric primitives

New guidance regarding features for which the encoding combination of object class and geometric primitive results in no display of the feature in ECDIS was included in UOC Edition 3.0.0 (October 2011) – Clauses 2.5; 4.6.6.6; 4.7.4; 4.7.7.1; 4.7.7.2; 4.7.11; 4.8.3; 4.8.5; 4.8.8; 4.8.10; 4.8.12; 4.8.13 and 11.6.1.

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EB30 - UOC Clause 12.8.7 Various special types of lights

New guidance regarding the encoding of strip lights serving the purpose of an aid to navigation was included in UOC Edition 3.0.0 (October 2011) – Clause 12.8.7.

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EB31 - ENC PS Clause 5.7 Updating and UOC Clause 2.6 Updating

New guidance regarding changing the area of data coverage of a published ENC cell and the maximum recommended file size for an ENC Update (ER) cell was included in UOC Edition 3.0.0 (October 2011) – Clause 2.6.

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EB32 - UOC Clause 6.2.1 Wrecks

Revised encoding guidance regarding the population of attributes for WRECKS objects to aid in enhanced ECDIS portrayal was included in UOC Edition 3.0.0 (October 2011) – Clause 6.2.1.

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EB33 - ENC PS Clause 3.1 Feature Object Identifiers

New encoding guidance regarding the population of the Feature Object Identifier (FOID) field was included in UOC Edition 3.0.0 (October 2011) – Clause 2.1.8.1.

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EB34 - UOC Clause 12.1.2 Relationships

Revised guidance regarding the encoding of master to slave relationships for navigational aids, and the encoding of navigational aid base structures (on land or in the water) where the nature of the base structure is unknown, was included in UOC Edition 3.0.0 (October 2011) – Clause 12.1.2.

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EB35 - UOC Clause 6.2.2 Obstructions, foul area and foul ground

New encoding guidance regarding the distinction between areas considered to be “foul areas” and areas considered to be “foul ground” was included in UOC Edition 3.0.0 (October 2011) – Clause 6.2.2.

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EB36 - UOC Clause 11.7.4 Offshore production areas

New guidance regarding the encoding of offshore wind turbines and wind farms, wave energy devices, underwater turbines, and wave or current farms was included in UOC Edition 3.0.0 (October 2011) – Clause 11.7.4.

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EB37 - UOC Clause 1.1.1 References within S-57 to other IHO publications

New advice regarding outdated references to IHO publications within S-57 documentation was included in UOC Edition 3.0.0 (October 2011) – Clause 1.1.1.

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EB38 - UOC Clause 5.5 Dredged areas

Revised guidance regarding the encoding of the date of dredging for dredged areas was included in UOC Edition 3.0.0 (October 2011) – Clause 5.5.

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EB39 - UOC Clause 6.6 Caution areas

New encoding guidance regarding the avoidance of the overuse of CTNARE and the geographic extent of encoded CTNAREs was included in UOC Edition 3.0.0 (October 2011) – Clauses 2.5 and 6.6.

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EB40 - UOC Clauses 10.2.2.1 Deep water route parts; 10.2.3 Traffic separation scheme systems; and 10.2.6 Two-way routes

New guidance regarding the encoding of relationships between deep water routes, traffic separation schemes and two-way routes, and other routeing measures was included in UOC Edition 3.0.0 (October 2011) – Clauses 10.2.2.1; 10.2.3 and 10.2.6.

EB41 - UOC Clause 15 Collection objects

Revised guidance regarding the encoding of navigationally relevant information on C_AGGR and C_ASSO objects was included in UOC Edition 3.0.0 (October 2011) – Clause 15.

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EB42 - UOC Clause 9.2.1 Anchorage Areas

New guidance regarding the encoding of anchorages such that the name displays in ECDIS has been included in UOC Edition 3.1.0 (October 2012) – Clause 9.2.1.

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EB43 - UOC Clauses 6.1.2 Rocks which may cover; 6.2.1 Wrecks; and 6.2.2 Obstructions, foul areas and foul ground

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EB44 - UOC Clause 3.1.1 Magnetic variation

New guidance regarding the encoding magnetic variation information as areas in ENCs has been included in UOC Edition 3.1.0 (October 2012) – Clause 3.1.1.

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EB45 - UOC Clause 5.8 Areas with inadequate depth information

New guidance regarding the encoding of bathymetry where source data is limited to satellite imagery has been included in UOC Edition 3.1.0 (October 2012) – Clause 5.8.1.1.

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EB46 UOC Section 2 Cartographic framework

New guidance regarding the encoding of features in their true position where they may be displaced on the paper chart for cartographic reasons has been included in UOC Edition 3.1.0 (October 2012) – Clause 2.7.

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EB47 UOC Clause 4.7.11 Vegetation

New guidance regarding the encoding of mangroves in the intertidal area has been included in UOC Edition 3.1.0 (October 2012) – Clause 4.7.11.

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EB48 - UOC Clause 2.8.1 Wide blank area

New guidance regarding the spatial extent of the M_COVR objects comprising an ENC data set has been included in UOC Edition 3.1.0 (October 2012) – Clause 2.8.1.

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EB49 - UOC clause 2.3 Textual information

New guidance clarifying the use of the attributes INFORM, NNFOM, TXTDSC and NTXTDS has been included in UOC Edition 3.1.0 (October 2012) – Clause 2.3.

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EB50 - UOC clause 4.8.20 Views and sketches, viewpoints

• New guidance regarding the recommended format and content of the associated picture files referenced by the attribute PICREP has been included in UOC Edition 3.1.0 (October 2012) – Clause 4.8.20. 

EB51 - UOC section 4 Topography

New guidance regarding the recommended level of topographic depiction for ENCs has been included in UOC Edition 3.1.0 (October 2012) – Clause 4.

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EB52 - UOC clause 2.7 Multiple objects

New guidance clarifying the requirement to indicate multiple objects where they have been generalised to a single object on the source has been included in UOC Edition 3.1.0 (October 2012) – Clause 2.7.

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EB53 - UOC Clause 12.8.1 Description of lights

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EB54 - UOC Clause 12.14.1 AIS equipped aids to navigation

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EB55 - UOC Clause 12.4.1.1 Emergency wreck marking buoys

Revised guidance regarding the population of the attribute SIGSEQ for the LIGHTS object on an IALA compliant emergency wreck marking buoy has been included in UOC Edition 4.1.0 (January 2018) - Clause 12.4.1.1.

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Revised guidance regarding encoding of "holes" in a Navigational Purpose coverage under the assumption that the ECDIS user will have the larger Navigational Purpose data available has been included in UOC Edition 4.1.0 (January 2018) - Clause 2.8.1.

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EB58 - UOC Clause 10.2.7 Areas to be avoided

Revised guidance regarding the encoding of value 14 (area to be avoided) for the attribute RESTRN has been included in UOC Edition 4.1.0 (January 2018) – Clause 10.2.7.

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EB59 UOC Clause 12.1.2 Relationships – Lights

New guidance regarding the encoding of omnidirectional lights on land of nominal range 10 Nautical Miles or greater, where the nature of the structure object is unknown, has been included in UOC Edition 4.1.0 (January 2018) – Clause 12.1.2.

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EB60 UOC Clause 2.1.8 Seamless ENC coverage

New guidance regarding overlapping data within cells having the same compilation scale and different Navigational Purposes has been included in UOC Edition 4.1.0 (January 2018) – Clause 2.1.8.

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EB61 UOC Clause 4.8.14 Built-up areas

New guidance regarding the encoding of built-up areas extending into navigable water has been included in UOC Edition 4.1.0 (January 2018) – Clause 4.8.14.
 

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EB63 UOC Clause 2.2.3.1 Quality of bathymetric data

New guidance regarding the encoding of M_QUAL over UNSARE carrying no depth data or bathymetry has been included in UOC Edition 4.3.0 (October 2022) – Clause 2.2.3.1.

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EB64 UOC Clause 2.6 Updating

An ECDIS display anomaly has been identified in some ECDIS when the following changes to the ENC dataset are applied using the ENC Update (ER file) mechanism:

1. The deletion of a Group 1 feature of class DEPARE or DRGARE that overlaps at least one WRECKS, OBSTRN, or UWTROC feature.

2. A change to the geometry of a Group 1 feature of class DEPARE or DRGARE in a way that the relationship with the set of WRECKS, OBSTRN, or UWTROC features that it overlaps is different before and after the change.

NOTE: It may be difficult to determine in some cases if a particular Group 1 Update instruction falls into one of the two above categories. Hence software tools have been made available to assist Data Producers by applying an additional validation check against any potentially impacted ENC Update file.  This validation check has been included in the following versions of ENC data validation software:

7Cs Analyzer Version 5.0.2.4;

dKart Editor Version 3.4.2.1815 and dKart Inspector Version 6.4.2.3518.

Encoders are strongly advised, therefore, that where such changes to an ENC dataset are required a New Edition of the ENC should be issued, unless validation of the corresponding ENC Update reports no related errors when validated using the versions of the software tools listed in the Note above.

This action is needed in the short term to minimise the risk of some ECDIS not displaying isolated dangers correctly.  Data Producers will be notified when the anomaly has been rectified.

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EB65 Duplicate RCNM_RCID Combinations

A potential ECDIS anomaly has been identified in cases where the record identifier NAME (concatenation of the RCNM and RCID subfields) has been used more than once in any dataset (Base dataset (EN) file and all subsequent Update (ER) files) applicable to a single Edition of an ENC.

Encoders are advised, therefore, that reusing the record identifier NAME (concatenation of the RCNM and RCID subfields) must be avoided. This issue is normally not identified until the data has been issued via a service provider. Where this occurs, Data Producers must release the ENC as a New Edition; and should contact their production software providers to provide a permanent solution.

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EB66 Objects with 7 or more values populated for attribute RESTRN

An ECDIS issue has been identified in some ECDIS, causing the machine to crash when attempting to load ENC datasets (EN or ER) containing Objects having 7 or more values populated for the List type attribute RESTRN. This problem occurs for all Object Classes except for RESARE and NEWOBJ.

Encoders are advised, therefore, to limit the number of values populated for a single instance of the attribute RESTRN to a maximum of 6, with preference being given to those that have the greatest impact on navigational safety and environmental protection. If it is considered necessary to encode additional RESTRN values, these should be populated using the attribute INFORM, for example Additional restrictions: fishing restricted; diving prohibited, on the same Object instance that carries RESTRN.

This issue is normally not identified until the data has been issued via a Service Provider. Where this occurs, Data Producers must apply the appropriate changes and release the ENC as a New Edition.

This action is needed in the short term to minimise the risk of some ECDIS crashing when attempting to load an ENC dataset.  Data Producers will be notified when the issue has been rectified and this Encoding Bulletin will be cancelled.

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