Rule 22 — Visibility of lights

The lights prescribed in these Rules shall have an intensity as specified in Section 8 of Annex I to these Regulations so as to be visible at the following minimum ranges:

(a) In vessels of 50 metres or more in length:

a masthead light, 6 miles; - a sidelight, 3 miles; - a stern light, 3 miles; - a towing light, 3 miles; - a white, red, green or yellow all-round light, 3 miles.

(b) In vessels of 12 metres or more in length but less than 50 metres in length: - a masthead light, 5 miles; except that where the length of the vessel is less than 20 metres, 3 miles; - a sidelight, 2 miles;

a sternlight, 2 miles;
a towing light, 2 miles; - a white, red, green or yellow all-round light, 2 miles.

(c) In vessels of less than 12 metres in length: - a masthead light, 2 miles; - a sidelight, 1 mile; - a sternlight, 2 miles; - a towing light, 2 miles - a white, red, green or yellow all-round light, 2 miles.

(d) In inconspicuous, partly submerged vessels or objects being towed: - a white all-round light, 3 miles.

MSN 1781 (M+F): Rules text stated on the document as amended through IMO Res A.910(22); read with MSN 1781 (M+F) Amendment 3 (21 Nov 2023, current — replaces Amendment 2; scope-only change for the Merchant Shipping (Watercraft) Order 2023). Per Amendment 2 Appendix 2, the only later wording changes are Annex IV (A.1004(25)) and new Part F Rules 39-41 (A.1085(28)).

Contains public sector information reproduced under the Open Government Licence v3.0. Source: MSN 1781.

Independent preparatory study aligned to the MCA OOW (Yachts <3000 GT) oral examination syllabus. Not an MCA-approved course and confers no credit toward a Certificate of Competency.