International Regulations for Preventing Collisions at Sea
The International Regulations for Preventing Collisions at Sea 1972 (COLREGs) are published by the International Maritime Organization (IMO) and set out, among other things, the "rules of the road" or navigation rules to be followed by ships and other vessels at sea to prevent collisions between two or more vessels. COLREGs can also refer to the specific political line that divides inland waterways, which are subject to their own navigation rules, and coastal waterways which are subject to international navigation rules. The COLREGs are derived from a multilateral treaty called the Convention on  the International Regulations for Preventing Collisions at Sea. Although rules for navigating vessels inland may differ, the international rules specify that they should be as closely in line with the international rules as possible. In most of continental Europe, the Code Européen des Voies de la Navigation Intérieure (CEVNI, or the European Code for Navigation on Inland Waters) apply. In the United States, the rules for vessels navigating inland are published alongside the international rules. The Racing Rules of Sailing, which govern the conduct of yacht and dinghy racing under the sanction of national sailing authorities which are members of  World Sailing, are based on the COLREGs, but differ in some important matters such as overtaking and right of way close to turning marks in competitive sailing. History. Prior to the development of a single set of international rules and practices, there existed separate practices and various conventions and informal procedures in different parts of the world, as advanced by various maritime nations. As a result, there were inconsistencies and even contradictions that gave rise to unintended collisions. Vessel navigation lights for operating in darkness as well as navigation marks also were not standardised, giving rise to dangerous confusion and  ambiguity between vessels at risk of colliding. With the advent of steam-powered ships in the mid-19th century, conventions for sailing vessel navigation had to be supplemented with conventions for power-driven vessel navigation. Sailing vessels are limited as to their manoeuvrability in that they cannot sail directly into the wind and cannot be readily navigated in the absence of wind. On the other hand, steamships can manoeuvre in all 360 degrees of direction and can be manoeuvred irrespective of the presence or absence of wind. In 1840 in London, the Trinity House drew up a set of  regulations which were enacted by Parliament in 1846. The Trinity House rules were included in the Steam Navigation Act 1846, and the Admiralty regulations regarding lights for steam ships were included in this statute in 1848. In 1849 Congress extended the light requirements to sailing vessels on US waters. In the UK in 1858 coloured sidelights were recommended for sailing vessels and fog signals were required to be given, by steam vessels on the ship's whistle and by sailing vessels on the fog horn or bell, while a separate but similar action was also taken in the United States . In 1850, English maritime law was being adopted in the United States. Also in 1850, courts in the England and the United States adopted common law pertaining to reasonable speed within the Assured Clear Distance Ahead. In 1863 a new set of rules drawn up by the British Board of Trade, in consultation with the French government, came into force. By 1864 the regulations (or Articles) had been adopted by more than thirty maritime countries, including Germany and the United States (passed by the United States Congress as "Rules to prevent Collisions at Sea." An act fixing certain rules and  regulations for preventing collisions on the water. 29 April 1864, ch. 69. and signed into law by President Abraham Lincoln). In 1867, Thomas Gray, assistant secretary to the Maritime Department of the Board of Trade, wrote "The Rule of the Road", a pamphlet that became famous for its well-known mnemonic verses. In 1878, the United States codified its common law rules for preventing collisions. In 1880, the 1863 Articles were supplemented with whistle signals and in 1884 a new set of international regulations was implemented. In 1889 the United States convened the first international maritime conference in Washington, D.C.  The resulting rules were adopted in 1890 and effected in 1897. Some minor changes were made during the 1910 Brussels Maritime Conference and some rule changes were proposed, but never ratified, at the 1929 International Conference on Safety of Life at Sea (S.O.L.A.S.) With the recommendation that the direction of a turn be referenced by the rudder instead of the helm or tiller being informally agreed by all maritime nations in 1935. The 1948 S.O.L.A.S. International Conference made several recommendations, including the recognition of radar these were eventually ratified in 1952 and became effective in 1954. Further recommendations were made  by a S.O.L.A.S. Conference in London in 1960 which became effective in 1965. The "International Regulations for Preventing Collisions at Sea" were adopted as a convention of the International Maritime Organization on 20 October 1972 and entered into force on 15 July 1977. They were designed to update and replace the Collision Regulations of 1960, particularly with regard to Traffic Separation Schemes (TSS) following the first of these, introduced in the Strait of Dover in 1967. As of June 2013, the convention has been ratified by 155 states representing 98.7% of the tonnage of the world's merchant fleets. They  have been amended several times since their first adoption. In 1981 Rule 10 was amended with regard to dredging or surveying in traffic separation schemes. In 1987 amendments were made to several rules, including rule 1(e) for vessels of special construction; rule 3(h), vessels constrained by her draught and Rule 10(c), crossing traffic lanes. In 1989 Rule 10 was altered to stop unnecessary use of the inshore traffic zones associated with TSS. In 1993 amendments were made concerning the positioning of lights on vessels. In 2001 new rules were added relating to wing-in-ground-effect (WIG) craft and in  2007 the text of Annex IV (Distress signals) was rewritten. Jurisdictions. The International Maritime Organization (IMO) convention, including the almost four dozen "rules" contained in the international regulations, must be adopted by each member country that is signatory to the convention—COLREG laws must exist within each jurisdiction. Thereafter, each IMO member country must designate an "administration"—national authority or agency—for implementing the provisions of the COLREG convention, as it applies to vessels over which the national authority has jurisdiction. Individual governing bodies must pass legislation to establish or assign such authority, as well as to create national navigation laws  (and subsequent specific regulations) which conform to the international convention; each national administration is thereafter responsible for the implementation and enforcement of the regulations as it applies to ships and vessels under its legal authority. As well, administrations are typically empowered to enact modifications that apply to vessels in waters under the national jurisdiction concerned, provided that any such modifications are not inconsistent with the COLREGs. Canada. The Canadian version of the COLREGs is provided by Transport Canada, which regulates Canadian vessels. United Kingdom. The UK version of the COLREGs is provided by the Maritime and Coastguard Agency (MCA), in  the "Merchant Shipping (Distress Signals and Prevention of Collisions) Regulations of 1996." They are distributed and accessed in the form of a "Merchant Shipping Notice" (MSN), which is used to convey mandatory information that must be complied with under UK legislation. These MSNs relate to Statutory Instruments and contain the technical detail of such regulations. Material published by the MCA is subject to Crown copyright protection, but the MCA allows it to be reproduced free of charge in any format or medium for research or private study, provided it is reproduced accurately and not used in a misleading context. United  States. The US version of the COLREGs is provided by the US Coast Guard of the US Department of Homeland Security. No right-of-way. A commonly held misconception concerning the rules of marine navigation is that by following specific rules, a vessel can gain certain rights of way over other vessels. No vessel ever has "right of way" over other vessels. Rather, there can be a "give way" vessel and a "stand on" vessel, or there may be two give way vessels with no stand on vessel. A stand on vessel does not have any right of way over  any give way vessel, and is not free to maneuver however it wishes, but is obliged to keep a constant course and speed (so as to help the give way vessel in determining a safe course). So standing on is an obligation, not a right, and is not a privilege. Furthermore, a stand on vessel may still be obliged (under Rule 2 and Rule 17) to give way itself, in particular when a situation has arisen where a collision can no longer be avoided by actions of the give way vessel alone. For example, two power-driven vessels approaching each  other head-to-head, are "both" deemed to be "give way" and both are required to alter course so as to avoid colliding with the other. Neither vessel has "right of way".