INTERNATIONAL MARITIME ORGANIZATION
E
IMO
SUB-COMMITTEE ON SAFETY OF
NAVIGATION
52nd session
Agenda item 14
NAV 52/WP.2
17 July 2006
Original: ENGLISH
CONSIDERATION OF IACS UNIFIED INTERPRETATIONS
Draft MSC circulars relating to Unified Interpretations (UI) of
COLREGs 1972, as amended and SOLAS chapter V
Note by the Chairman
1
Attached at annex 1 and annex 2 are two draft MSC circulars relating to Unified
Interpretations (UI) of COLREGs 1972, as amended and SOLAS chapter V for consideration.
Action requested of the Sub-Committee
2
The Sub-Committee is invited to consider the draft MSC circulars and forward them to
the Committee for approval.
***
For reasons of economy, this document is printed in a limited number. Delegates are
kindly asked to bring their copies to meetings and not to request additional copies.
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NAV 52/WP.2
ANNEX 1
DRAFT MSC CIRCULAR
UNIFIED INTERPRETATIONS OF COLREGs 1972
1
The Maritime Safety Committee, [at its eighty-second session (29 November to
8 December 2006)], with a view to providing more specific guidance for certain Rules, which are
open to different interpretations contained in IMO instruments, approved the unified
interpretations of COLREGs prepared by the Sub-Committee on Safety of Navigation, as set out
in the annex.
2
Member Governments are invited to use the annexed unified interpretations as guidance
when applying relevant provisions of COLREGs to ships on or after [1 July 2006] and to bring
the unified interpretations to the attention of all parties concerned.
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NAV 52/WP.2
ANNEX 1
Page 2
ANNEX
UNIFIED INTERPRETATIONS OF COLREGs 1972[, AS AMENDED]
Rule 23(a) – Power-driven vessels underway
Navigation lights (masthead light(s), sidelights and sternlight) installed on board shall be
duplicated or shall be fitted with duplicate lamps.
Rule 27(b)(i) – Vessels not under command or restricted in their ability to manoeuvre
“Not under command” (NUC) all-round red lights (Rule 27(a)(ii) may be used as part of
the “Restricted Ability to Manoeuvre” (RAM) lights provided the vertical and horizontal
distances required by COLREG 1972 are complied with and the electrical system is arranged so
that the all-round white light (RAM) may be switched on independently from the two all-round
red lights (NUC).
Annex I, Section 3(b) – Horizontal positioning and spacing of lights
The term “near the side” is interpreted as being a distance of not more than 10% of the breadth of
the vessel inboard from the side, up to a maximum of 2 metres. Where the application of above
requirement is impractical (e.g. small ships with superstructure of reduced width) exemption may
be given on the basis of the Flag Authority acceptance.
Annex I, Section 9(b) – Horizontal sectors
In order to comply with the 1 mile requirement in 9(b)(ii), the all-round lights shall be screened
less than 180 degrees. However, as a light source is not a point but has a certain extension, it
may be accepted that all-round lights are screened up to 180 degrees. Screening details are to be
considered by Societies when carrying out the drawing approval process.
***
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NAV 52/WP.2
ANNEX 2
DRAFT MSC CIRCULAR
UNIFIED INTERPRETATIONS OF SOLAS CHAPTER V
1
The Maritime Safety Committee, [at its eighty-second session (29 November to
8 December 2006)], with a view to providing more specific guidance for vague expressions such
as “other means”, which are open to different interpretations contained in IMO instruments,
approved the unified interpretations of SOLAS chapter V prepared by the Sub-Committee on
Safety of Navigation, as set out in the annex.
2
Member Governments are invited to use the annexed unified interpretations as guidance
when applying relevant provisions of SOLAS chapter V to construction, installation,
arrangements and equipment to be installed on board ships on or after [1 July 2006] and to bring
the unified interpretations to the attention of all parties concerned.
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ANNEX 2
Page 2
ANNEX
UNIFIED INTERPRETATIONS OF SOLAS CHAPTER V
Regulation V/19.2.5.1 – Shipborne navigational equipment and systems
A gyrocompass can be fitted, as the “other means” mentioned in regulation V/19.2.2.1, to
comply with that regulation. However, this gyrocompass:
-
cannot be credited to fulfil regulation V/19.2.5.1; and
shall be fed by both main and emergency power supply and, in addition, it shall be
provided with a transitional source of power (e.g. a battery).
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