This is the full text of the COLREG rules 1 to 38 retold in plain English, rule by rule, with the wording of the convention next to each explanation. Every rule has a real sea example: what you see, what you do, and what happens if you get it wrong.
Looking for something specific? The lights and shapes of part C are drawn from three angles on the navigation lights page, the whistle, bell and gong signals of part D can be played on the sound signals page, and 118 COLREG flashcards drill the same material with spaced repetition.
Frequently asked rules: rule 5 look-out, rule 6 safe speed, rule 13 overtaking, rule 14 head-on, rule 15 crossing, rule 18 responsibilities between vessels, rule 19 restricted visibility.
Rule index
General
Where these rules apply, who answers for breaking them, and who is called what.
Rule 1 Where the rules apply
The rules apply on the high seas and in all waters connected to them that are navigable by seagoing vessels. Local authorities may make special rules for roadsteads, harbours, rivers and lakes, but those must conform as closely as possible to these. Warships, vessels in convoy and fishing fleets may carry additional lights and signals, provided they cannot be mistaken for the prescribed ones.
On a river you are under the local inland rules. Once you are outside in open water the COLREGs apply. If you see an unfamiliar light pattern on a warship, that is a permitted national signal, but by design it must not read as «not under command».
Rule 2 Responsibility and the right to depart from the rules
Two short paragraphs that carry more weight than any other. First: following the rules does not exonerate you if you neglected the ordinary practice of seamen or the special circumstances of the case. Second: in construing and complying with the rules, due regard shall be had to all dangers of navigation and collision and to any special circumstances, including the limitations of the vessels involved, which may make a departure from these rules necessary to avoid immediate danger.
You are the stand-on vessel and must keep your course. The other one is not turning and you have thirty seconds left. Rule 2 says holding your course «because the book says so» and hitting her makes it your fault too. Turn whichever way saves the situation.
Rule 2. Responsibility and the right to depart from the rules
Rule 3 Who is called what
The definitions decide who gives way. The commonest confusion is between two similar terms:
- Not under command: through some exceptional circumstance she is unable to manoeuvre as required. This is a breakdown.
- Restricted in ability to manoeuvre: unable to manoeuvre because of the nature of her work. Laying or lifting cable or pipeline, dredging, survey, replenishment underway, launching or recovering aircraft, mine clearance, a tow that severely restricts deviation.
- Constrained by her draught: a power-driven vessel only, whose draught in relation to the available depth and width of navigable water severely restricts her ability to deviate from her course.
- Underway: not at anchor, not made fast to the shore, not aground. Note: underway does not mean moving, a drifting vessel is underway too.
- Engaged in fishing: only when the gear restricts her manoeuvrability. Trolling lines do not count.
- In sight of one another: only when one can be observed visually from the other. A radar contact is not in sight.
- Restricted visibility: fog, mist, falling snow, heavy rainstorms, sandstorms and any similar cause.
A deep-laden tanker in a dredged channel is constrained by her draught, not restricted in ability to manoeuvre. A working dredger is restricted in ability to manoeuvre. A ship with a jammed rudder is not under command. Three different light sets. The first two sit in the give-way order of rule 18, while a vessel constrained by her draught is only one whose safe passage others must avoid impeding.
Always: clear weather and fog alike
These seven rules apply in any visibility, whether you can see the other vessel or only hear her.
Rule 4 This section applies in any visibility
One line: the rules of this section apply in any condition of visibility.
Fog does not suspend the duty to keep a look-out and to proceed at a safe speed, it sharpens it.
Rule 5 Look-out
Keep a proper look-out by sight, by hearing and by all available means, so as to make a full appraisal of the situation and the risk of collision. Radar and AIS do not replace a pair of eyes at the window, they are added to them.
An officer buried in the radar display missed a small yacht with no radar reflector alongside. That is a breach of rule 5, the rule most often cited in collision investigations.
Rule 6 Safe speed
Safe speed is the speed at which you can take proper and effective action and stop within a distance appropriate to the prevailing circumstances. It is not a number from a table, it is a conclusion drawn from conditions.
- All vessels: state of visibility, traffic density including concentrations of fishing vessels, manoeuvrability and stopping distance, at night the background of shore lights and backscatter from your own lights, wind, sea and current, proximity of navigational hazards, draught in relation to the available depth.
- Vessels with operational radar in addition: the characteristics and limitations of the set, the range scale in use, the effect of sea state and weather on detection, the fact that small craft and ice may not be detected, and the number, location and movement of the contacts.
In fog with 300 metres of visibility full speed is unsafe for any ship: a large vessel stops in kilometres. Safe speed here is the speed at which you can stop within the visibility.
Rule 7 Risk of collision
The master rule of doubt: if in doubt, assume the risk exists. Determine it by all available means, not by eye alone.
- If the compass bearing of an approaching vessel does not appreciably change, risk of collision exists.
- Risk may exist even with an appreciably changing bearing: with a very large vessel, with a tow, or when closing at short range.
- Use radar properly if fitted and working: long-range scanning for early warning, and radar plotting or equivalent systematic observation of the contacts.
- Do not make assumptions on the basis of scanty information, especially scanty radar information.
A light stays exactly 40 degrees on your starboard bow and has not moved for five minutes, only grown. The bearing is constant, so you are heading for the same point of water. Act now.
Rule 8 How to manoeuvre so you are understood
Action must be positive, made in ample time and with due regard to good seamanship, if the circumstances of the case admit. A succession of small alterations is to be avoided precisely because nobody can see them, by eye or on radar.
- Any alteration of course or speed must be large enough to be readily apparent to the other vessel. A succession of small alterations is a classic mistake.
- If there is sea room, an alteration of course alone may be the most effective action, provided it is made in good time and is substantial.
- Action must result in passing at a safe distance, and its effectiveness must be checked until the other vessel is finally past and clear.
- You may and should slacken speed, stop or reverse if that is safer or you need time to appraise the situation.
- «Not to impede» means taking early action to leave enough room for the other vessel to pass safely, not swerving at the last moment. The duty does not lapse when risk of collision develops.
Meeting a vessel head on, a 5-degree turn is invisible to her and you keep closing. A 25 or 30-degree turn made three miles off reads instantly by eye and on radar. That is positive action.
Rule 9 Narrow channels
In a narrow channel or fairway keep to the starboard side, as near to the outer limit as is safe and practicable.
- A vessel under 20 m and a sailing vessel shall not impede the passage of a vessel that can safely navigate only within a narrow channel or fairway.
- A vessel engaged in fishing shall not impede the passage of any other vessel navigating within a narrow channel or fairway.
- Do not cross a channel if crossing impedes a vessel that can navigate only within it. She may sound five short blasts if in doubt about your intentions.
- Overtaking in a channel: where overtaking is possible only if the vessel to be overtaken takes action to permit safe passing, the overtaking vessel must signal her intention and the other must answer her agreement and take those steps. That agreement does not release the overtaking vessel from rule 13.
- Approaching a bend where other vessels may be obscured: one prolonged blast and particular alertness.
- Avoid anchoring in a narrow channel.
A large container ship in a canal physically cannot leave the dredged strip. Your 12-metre yacht may be there, but must not impede her: get over and let her through.
Rule 10 Traffic separation schemes
These are the sea lanes on approaches to ports and in straits. Inside them you proceed in the appropriate traffic lane in the general direction of traffic flow, keeping clear of the separation line or zone.
- Join and leave at the ends of the lane. From either side, do it at as small an angle as practicable to the general direction of flow.
- Avoid crossing lanes. If you must cross, do it on a heading as nearly as practicable at right angles to the general direction of flow: you clear the lane fastest and your aspect is unmistakable.
- Do not use an inshore traffic zone when you can safely use the lane. Exceptions: vessels under 20 m, sailing vessels, vessels engaged in fishing, and vessels going to or from a port, offshore installation or pilot station inside the zone.
- A fishing vessel must not impede any vessel following a lane. A vessel under 20 m or a sailing vessel must not impede a power-driven vessel following a lane.
- Avoid anchoring in the scheme or near its ends. If you are not using the scheme, keep well clear of it.
Crossing the Dover Strait diagonally to shorten the trip is a breach. You steer 90 degrees to the flow even if the tide sets you sideways.
When you can see each other
These rules switch on only in sight of one another. A contact seen on radar alone falls under section III instead.
Rule 11 When this section applies
Only when vessels are in sight of one another, that is, one can actually be seen from the other.
In fog you have a target two miles off on radar. Rules 12 to 18 do not yet apply to you: rule 19 does.
Rule 12 Sailing vessel against sailing vessel
Three cases, checked in order:
- Different tacks: the vessel on the port tack (wind on her port side) keeps out of the way.
- Same tack: the vessel to windward keeps out of the way of the vessel to leeward.
- On the port tack, seeing a vessel to windward and unable to determine her tack: keep out of her way.
- The windward side is the side opposite to that on which the mainsail is carried, or, with a square rig, opposite to the side on which the largest fore-and-aft sail is carried.
You have the wind on your starboard side, she has it on her port side. She keeps clear. If both of you have it to starboard, the one higher up the wind keeps clear: bearing away is easier for her.
Rule 13 Overtaking
The overtaking vessel always keeps out of the way, and this rule overrides the crossing rules. Overtaking is defined by geometry: you are coming up from more than 22.5 degrees abaft her beam, that is, at night you see only her sternlight and neither sidelight.
- If in doubt whether you are overtaking, assume that you are and keep clear.
- No subsequent change of bearing between the two makes you a crossing vessel or releases you until you are finally past and clear.
At night, fine on your starboard bow, you see one white sternlight and no sidelights. You are inside her stern sector and you are the overtaking vessel: the whole duty is yours even though she is «on your starboard side».
Rule 14 Head-on situation
Two power-driven vessels meeting on reciprocal or nearly reciprocal courses: each alters course to starboard so they pass port to port. Not one of them, each.
- The situation exists when you see her ahead or nearly ahead, and by night her masthead lights in a line and/or both sidelights.
- If in doubt whether such a situation exists, assume that it does and alter to starboard.
At night you see a red and a green sidelight at the same time with white lights in a line between them. She is bow-on. Both turn to starboard and you pass port to port.
Rule 15 Crossing situation
Two power-driven vessels crossing: the one that has the other on her own starboard side keeps out of the way and, if the circumstances of the case admit, avoids crossing ahead of the other, that is, turns to starboard and passes astern.
At night you see a red sidelight on your starboard side: you are looking at her port side, she is crossing from right to left ahead of you. Red means stop, you give way. A green light means you see her starboard side, she gives way, and you keep your course and speed.
Rule 16 Action by the give-way vessel
Early and substantial action to keep well clear. Not «a little bit and let us see».
Giving way to a vessel crossing from starboard: reduce speed and turn to starboard two or three miles off, not three cables off.
Rule 17 Action by the stand-on vessel
Keep your course and speed, so your behaviour is predictable. But this is not a duty to hold on into a collision:
- As soon as it becomes apparent that the give-way vessel is not taking appropriate action, you may manoeuvre yourself.
- When you find yourself so close that collision cannot be avoided by her action alone, you shall take the action that best aids to avoid collision.
- In a crossing situation, a power-driven vessel taking action of her own shall not, if the circumstances admit, alter course to port for another power-driven vessel on her own port side.
- This rule does not relieve the give-way vessel of her obligation.
You stand on, she is to starboard and does not turn. At two miles you sound five short blasts. At one mile you reduce speed and turn to starboard yourself: port is barred, that is where she is.
Rule 18 Responsibilities between vessels
The order from the top down. Each gives way to everyone above her:
- A vessel not under command.
- A vessel restricted in her ability to manoeuvre.
- A vessel engaged in fishing (which gives way so far as possible).
- A sailing vessel.
- A power-driven vessel: she gives way to all of the above.
- Separately: any vessel other than the first two shall, if the circumstances of the case admit, avoid impeding the safe passage of a vessel constrained by her draught, showing three all-round reds or a cylinder. That vessel must herself navigate with particular caution.
- A seaplane on the water keeps well clear of all vessels. A WIG craft taking off, landing and in flight near the surface keeps well clear of all vessels; on the water she is an ordinary power-driven vessel.
The bridge mnemonic: cannot, will not, fisher, sail, power. But rules 9, 10 and 13 override this order: in a channel and in a traffic lane a sailing vessel and a fishing vessel must not impede a big ship, and the overtaking vessel always keeps clear.
In fog: you cannot see each other
Here there is no give-way vessel and no stand-on vessel: both are required to act.
Rule 19 Conduct of vessels in restricted visibility
This applies to vessels not in sight of one another when navigating in or near an area of restricted visibility. Proceed at a safe speed for those conditions and, if power-driven, keep your engines ready for immediate manoeuvre.
- If you detect another vessel by radar alone, determine whether a close-quarters situation is developing or risk of collision exists, and take avoiding action in ample time. If the action is an alteration of course, avoid an alteration to port for a vessel forward of the beam (other than one being overtaken) and an alteration towards a vessel abeam or abaft the beam.
- Except where it has been determined that a risk of collision does not exist: if you hear a fog signal apparently forward of your beam, or cannot avoid a close-quarters situation with a vessel forward of the beam, reduce your speed to the minimum at which you can be kept on course, and if necessary take all your way off and navigate with extreme caution until the danger is over.
In fog a radar target is fine on your port bow. The instinct to turn to port and pass astern of her is barred: she may herself be turning to starboard, as vessels do when meeting head on, and you would meet. Turn to starboard and take off speed instead.
Lights and shapes
The full three-angle diagrams live in the «Lights & shapes» tab. Here is what you need in words.
Rule 20 When each is shown
The rules of this part apply in all weathers. Lights shall be exhibited from sunset to sunrise, and during that time no other lights may be shown that could be mistaken for them or impair their visibility. In restricted visibility the lights shall be exhibited by day as well, and in all other circumstances they may be exhibited when it is deemed necessary. Shapes are exhibited by day.
Running into fog at noon: switch on your navigation lights, do not wait for dusk.
Rule 21 The kinds of light
Six definitions carry the whole of part C:
- Masthead light: a white light on the centreline showing 225 degrees, from right ahead to 22.5 degrees abaft the beam on either side.
- Sidelights: green to starboard, red to port, each showing 112.5 degrees, from right ahead to 22.5 degrees abaft the beam on its own side. Under 20 m they may be combined in one lantern.
- Sternlight: white, as near the stern as practicable, showing 135 degrees, 67.5 degrees on each side of right astern.
- Towing light: yellow, with the same characteristics as a sternlight.
- All-round light: shows the full 360 degrees.
- Flashing light: flashes at regular intervals at a frequency of 120 flashes or more per minute.
Add it up: the masthead 225 degrees plus the stern 135 makes 360. The sidelights cover the same forward arc as the masthead light. Hence the overtaking rule: 22.5 degrees abaft the beam is exactly where the sidelights stop and only the sternlight remains.
Rule 22 Ranges at which the lights must be visible
By length of vessel:
- 50 m or more: masthead 6 miles, sidelights, sternlight, towing light and all-round lights 3 miles.
- 12 m up to 50 m: masthead 5 miles (3 miles if under 20 m), the rest 2 miles.
- Under 12 m: masthead 2 miles, sidelights 1 mile, sternlight, towing light and all-round lights 2 miles.
- Inconspicuous, partly submerged object under tow: all-round white 3 miles.
A 10-metre yacht: her sidelights carry just one mile. At 20 knots of closing speed that mile is covered in three minutes, and the whole business of passing clear has to be settled inside those three minutes. That is exactly why small craft are told to be extra careful.
Rule 23 Lights of a power-driven vessel underway
The base set every other configuration builds on: a masthead light forward, a second masthead light abaft and higher (compulsory from 50 m, optional below), sidelights and a sternlight.
- An air-cushion vessel in non-displacement mode adds an all-round flashing yellow light.
- A WIG craft taking off, landing and in flight near the surface adds a high-intensity all-round flashing red light.
- Under 12 m: an all-round white plus sidelights is allowed. Under 7 m and not faster than 7 knots: an all-round white is enough, with sidelights if practicable.
At night you see two white lights in a line, the lower one nearer you, and a red sidelight. That is a large power-driven vessel crossing right to left, and if she is on your starboard side you give way.
Rule 24 Towing and pushing
A towing vessel shows two masthead lights in a vertical line instead of one, or three if the length of tow from her stern to the after end of the tow exceeds 200 m. Plus sidelights, a sternlight and a yellow towing light above the sternlight. Over 200 m she also shows a diamond by day.
- Pushing ahead or towing alongside: two masthead lights, sidelights, sternlight, and no yellow towing light.
- A pushing vessel and a vessel pushed ahead rigidly connected in a composite unit count as one power-driven vessel and show the lights of rule 23.
- A vessel towed: sidelights and a sternlight, plus a diamond if the tow exceeds 200 m. A vessel pushed ahead shows sidelights at the forward end; a vessel towed alongside shows sidelights forward and a sternlight.
- Inconspicuous partly submerged objects: all-round whites at the ends, two more at the sides from 25 m breadth, and over 100 m in length spaced so no gap exceeds 100 m, with a diamond at the after end.
You see two whites in a line, below them a yellow directly above a white, and half a mile behind, a lonely pair of sidelights with no masthead light. That is a tug and a barge: there is a wire between them and you never cross it.
Rule 25 Sailing vessels and vessels under oars
A sailing vessel underway shows sidelights and a sternlight, no masthead light. Under 20 m these may be combined in one lantern at the masthead. She may also show red over green all-round lights at the masthead, but not together with the combined lantern.
- A sailing vessel under 7 m and a vessel under oars: if she does not show those lights she must keep an electric torch or lighted lantern showing a white light ready and show it in time to prevent collision.
- Under sail and propelled by machinery: she is a power-driven vessel and by day must show a cone with the point down, forward where it can best be seen.
A yacht motorsailing without her cone is the classic breach: everyone reads her as a sailing vessel with right of way, while by the rules she is an ordinary power-driven vessel.
Rule 26 Fishing vessels
A vessel engaged in fishing shows only the lights and shapes of this rule, whether underway or at anchor.
- Trawling (dragging a dredge or other apparatus through the water): green over white all-round, by day two cones apexes together. Making way through the water: plus sidelights and a sternlight. From 50 m: plus a masthead light abaft and higher than the green.
- Fishing other than trawling (nets, lines): red over white all-round, with the same two-cone shape. Making way: plus sidelights and a sternlight.
- Gear extending more than 150 m horizontally: an all-round white or a cone point up in the direction of the gear.
- A vessel not engaged in fishing must not show these lights.
Mnemonic: green means she is going (trawling), red means she is sitting with static gear. A white light offset from a fishing vessel means the gear is over there, so pass the other side.
Rule 27 Not under command, restricted in ability to manoeuvre, divers, mine clearance
The busiest family of lights:
- Not under command: two all-round reds, by day two balls. Making way through the water she adds sidelights and a sternlight, but no masthead lights.
- Restricted in ability to manoeuvre: red, white, red all-round, by day ball, diamond, ball. With way on: plus masthead lights, sidelights and a sternlight. At anchor: plus the anchor lights.
- A tow that severely restricts deviation shows the towing lights and red, white, red.
- Dredging or underwater operations with an obstruction: additionally two all-round reds or two balls on the obstructed side and two all-round greens or two diamonds on the side another vessel may pass.
- Diving operations from a small vessel: red, white, red and a rigid replica of flag «A» not less than 1 m high, visible all round.
- Mine clearance: in addition to the lights of a power-driven vessel, three all-round greens or three balls, one near the foremast head and two at the fore yardarm ends. Meaning: it is dangerous to approach within 1000 m.
- Mine clearance: three all-round greens or three balls in addition to the lights for a power-driven vessel, or to the anchor lights if she is at anchor. One near the foremast head, two at the fore yardarm ends. Meaning: it is dangerous to approach within 1000 m.
- These are not distress signals: those are in Annex IV.
Three all-round lights at night: red, white, red says «I am restricted in my ability to manoeuvre, keep out of my way». Two reds says «I am not under command». One light apart, and the story behind it is different: the first is working, the second has broken down.
Rule 27. Not under command, restricted in ability to manoeuvre, divers, mine clearance
Rule 28 Constrained by draught
In addition to the lights of a power-driven vessel she may show three all-round reds in a vertical line, or a cylinder by day. It is a warning: I have no water to turn into.
Three reds in a line on the approach to a port is a loaded tanker in the channel. Under rule 18 every vessel except those not under command or restricted in ability to manoeuvre must avoid impeding her.
Rule 29 Pilot vessels
On pilotage duty: white over red all-round lights at or near the masthead. Underway she adds sidelights and a sternlight; at anchor, the anchor lights. Off pilotage duty she shows the ordinary lights for her length.
White over red on a pilot boarding ground is the pilot boat. The mnemonic: white over red, pilot ahead.
Rule 30 Anchored and aground
At anchor: an all-round white in the fore part and a second all-round white at or near the stern, lower than the first; a ball forward by day. Under 50 m she may show a single all-round white where best seen. A vessel of 100 m or more must also light her decks.
- Aground: the anchor lights plus two all-round reds in a vertical line, and three balls in a vertical line by day.
- A vessel under 7 m at anchor, away from narrow channels, fairways, anchorages and where vessels normally navigate, need not show them. A vessel under 12 m aground need not show the extra reds and balls.
Two white lights in an anchorage with no sidelights, the higher one nearer the bow: a vessel at anchor, not moving. Add two reds and she is aground, so give her a wide berth: it is shallow under her.
Rule 31 Seaplanes and WIG craft
Where it is impracticable to show lights and shapes of the prescribed characteristics or in the prescribed positions, she shows lights and shapes as close to the requirements as possible.
A seaplane has no mast for a masthead light: she shows what she physically can, but she must be conspicuous and must not mislead.
Sound and light signals
The full list of whistle signals lives in the «Sound signals» tab.
Rule 32 Short and prolonged
A whistle is any sound-signalling appliance capable of producing the prescribed blasts. A short blast lasts about 1 second. A prolonged blast lasts from 4 to 6 seconds.
Five short blasts means five crisp one-second blasts, not five long ones: long ones would say something else entirely.
Rule 33 What must be carried
12 m or more: a whistle. 20 m or more: a whistle and a bell. 100 m or more: also a gong whose tone cannot be confused with the bell. Bell and gong may be replaced by equivalent equipment, but manual sounding must always remain possible.
- Under 12 m she need not carry them, but must be provided with some other means of making an efficient sound signal.
On a yacht a hand-held aerosol horn is enough, but it must be aboard and working, not buried under the sails.
Rule 34 Manoeuvring and warning signals
In sight of one another, a power-driven vessel underway signals her manoeuvre on the whistle: one short blast means altering to starboard, two short altering to port, three short operating astern propulsion. The same meanings may be repeated with flashes of an all-round white light.
- Overtaking in a channel: two prolonged and one short means intending to overtake on your starboard side, two prolonged and two short on your port side. The other vessel agrees with prolonged, short, prolonged, short.
- At least five short and rapid blasts (and flashes if you like) mean «I do not understand your intentions» or «I doubt whether you are taking sufficient action». Sound it immediately.
- Approaching a bend in a channel: one prolonged blast, and any vessel round the bend within hearing must answer with the same.
- If whistles are fitted more than 100 m apart, only one whistle is used for manoeuvring and warning signals.
She is on your starboard side, must give way, and is not turning. Five short blasts is not swearing, it is the rule-book way to say «your actions are unclear to me», after which you may act on your own.
Rule 35 Sound signals in fog
In or near an area of restricted visibility, day or night. The core: one prolonged blast every 2 minutes at most means a power-driven vessel making way through the water; two prolonged means underway but stopped; one prolonged and two short means the special category; one prolonged and three short means a vessel towed.
- One prolonged and two short is sounded by: not under command, restricted in ability to manoeuvre, constrained by draught, sailing, engaged in fishing, towing or pushing. Fishing and RAM vessels working at anchor sound it too.
- At anchor: rapid ringing of the bell for about 5 seconds at intervals of not more than a minute. From 100 m: the bell forward and immediately the gong aft. She may add short, prolonged, short to warn an approaching vessel.
- Aground: three separate distinct strokes of the bell before and after the rapid ringing.
- A vessel from 12 up to 20 m need not sound the bell signals, and a vessel under 12 m need not sound any of the signals above at all. Both, however, must make some other efficient sound signal at intervals of not more than 2 minutes.
- A pilot vessel on duty may add an identity signal of four short blasts.
In fog you hear one prolonged blast forward of the beam: that is a vessel with way on. Rule 19 requires you to cut to minimum speed at once and be ready to stop.
Rule 36 Signals to attract attention
You may make any light or sound signal that cannot be mistaken for a prescribed signal, or direct a searchlight beam towards the danger in a way that does not embarrass other vessels. A light used to attract attention must not be capable of being mistaken for an aid to navigation. High-intensity intermittent or revolving lights, such as strobes, should be avoided.
A yacht that sees she is not being noticed may light up her own sail with a torch: sensible and allowed. Flashing a powerful strobe at the other bridge is not.
Rule 37 Distress signals
When in distress and requiring assistance, a vessel uses the signals of Annex IV: rockets and stars, a red parachute flare, orange smoke, continuous sounding of a fog-signalling apparatus, SOS, the spoken word «Mayday», flags N and C, slowly raising and lowering outstretched arms, the DSC alert and the EPIRB signal.
Five short blasts is not distress, it is doubt under rule 34. Distress is the continuous, unbroken sounding of a fog-signalling apparatus.
Exemptions
The historical part: vessels built before the rules came into force.
Rule 38 Who got a delay and for how long
Vessels whose keel was laid before the rules entered into force (15 July 1977) and that complied with the 1960 regulations were exempted: up to four years for the ranges of visibility of lights and their colour specifications; up to nine years for the repositioning of masthead lights on vessels of 150 m or more, for masthead and sidelights under Annex I and for sound-signalling appliances under Annex III; permanently for repositioning caused by the change from imperial to metric units, for masthead lights on vessels under 150 m and for the positioning of all-round lights.
Little practical weight today, but examiners ask it: the exemption for light ranges and colour is four years.
All 38 rules, one page each
- Rule 1 Where the rules apply
- Rule 2 Responsibility and the right to depart from the rules
- Rule 3 Who is called what
- Rule 4 This section applies in any visibility
- Rule 5 Look-out
- Rule 6 Safe speed
- Rule 7 Risk of collision
- Rule 8 How to manoeuvre so you are understood
- Rule 9 Narrow channels
- Rule 10 Traffic separation schemes
- Rule 11 When this section applies
- Rule 12 Sailing vessel against sailing vessel
- Rule 13 Overtaking
- Rule 14 Head-on situation
- Rule 15 Crossing situation
- Rule 16 Action by the give-way vessel
- Rule 17 Action by the stand-on vessel
- Rule 18 Responsibilities between vessels
- Rule 19 Conduct of vessels in restricted visibility
- Rule 20 When each is shown
- Rule 21 The kinds of light
- Rule 22 Ranges at which the lights must be visible
- Rule 23 Lights of a power-driven vessel underway
- Rule 24 Towing and pushing
- Rule 25 Sailing vessels and vessels under oars
- Rule 26 Fishing vessels
- Rule 27 Not under command, restricted in ability to manoeuvre, divers, mine clearance
- Rule 28 Constrained by draught
- Rule 29 Pilot vessels
- Rule 30 Anchored and aground
- Rule 31 Seaplanes and WIG craft
- Rule 32 Short and prolonged
- Rule 33 What must be carried
- Rule 34 Manoeuvring and warning signals
- Rule 35 Sound signals in fog
- Rule 36 Signals to attract attention
- Rule 37 Distress signals
- Rule 38 Who got a delay and for how long