International Regulations for Avoiding Collisions at Sea or IRPCS. The rules are specified in great detail in the regulations and the serious student is encouraged to seek the definitive document. Certain individuals are legally required to carry or possess a copy of the rules, such as the owners and/or operators of certain vessels. These legal requirements vary by jurisdiction. Consult the appropriate maritime authorities for each jurisdiction. Any individual subject to such requirements should obtain a complete, official copy from a government or official source. However, the rules are summarized below.
For the purpose of these Rules, except where the context otherwise requires:
(a) The word vessel includes every description of watercraft, including non-displacement craft and seaplanes, used or capable of being used as a means of transportation on water.
(b) The term power driven vessel means any vessel propelled by machinery.
(c) The term sailing vessel means any vessel under sail provided that propelling machinery, if fitted, is not being used.
(d) The term vessel engaged in fishing means any vessel fishing with nets, lines, trawls, or other fishing apparatus which restrict maneuverability, but does not include a vessel fishing with trolling lines or other fishing apparatus which do not restrict manageability.
(e) The term seaplane includes any aircraft designed to maneuver on the water.
(f) The term vessel not under command means a vessel which through some exceptional circumstance is unable to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel.
(g) The term vessel restricted in her ability to maneuver means a vessel which from the nature of her work is restricted in her ability to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel. The term vessel restricted in her ability to maneuver shall include but not be limited to:
(h) The term vessel constrained by her draft means a power driven vessel which because of her draft in relation to the available depth and width of navigable water is severely restricted in her ability to deviate from the course she is following.
(i) The word underway means a vessel is not at anchor, or made fast to the shore, or aground.
(j) The words length and breadth of a vessel mean her length overall and greatest breadth.
(k) Vessels shall be deemed to be in sight of one another only when one can be observed visually from the other.
(l) The term restricted visibility means any condition in which visibility is restricted by fog, mist, falling snow, heavy rainstorms, sandstorms and any other similar causes.
Part B - Steering and Sailing Rules
Section I - Conduct of Vessels in any Condition of Visibility
- Rule 4 : Application
- Rule 5 : Look-out
- Rule 6 : Safe Speed
- Rule 7 : Risk of Collision
- Rule 8 : Action to Avoid Collision
- Rule 9 : Narrow Channels
- Rule 10 : Traffic Separation Schemes
Section II - Conduct of Vessels in Sight of One Another
- Rule 11 : Application
- Rule 12 : Sailing Vessels
- Rule 13 : Overtaking
- Rule 14 : Head-on Situation
- Rule 15 : Crossing Situation
- Rule 16 : Action by Give-way Vessel
- Rule 17 : Action by Stand-on Vessel
- Rule 18 : Responsibilities Between Vessels
Section III - Conduct of Vessels in Restricted Visibility
Part C - Lights and Shapes
- Rule 20 : Application
- Rule 21 : Definitions
- Rule 22 : Visibility of Lights
- Rule 23 : power driven Vessels Underway
- Rule 24 : Towing and Pushing
- Rule 25 : Sailing Vessels Underway and Vessels Under Oars
- Rule 26 : Fishing Vessels
- Rule 27 : Vessels Not Under Command or Restricted in Their Ability to Maneuver
- Rule 28 : Vessels Constrained by their Draft
- Rule 29 : Pilot Vessels
- Rule 30 : Anchored Vessels and Vessels Aground
- Rule 31 : Seaplanes
Part D - Sound and Light Signals
- Rule 32 : Definitions
- Rule 33 : Equipment for Sound Signals
- Rule 34 : Maneuvering and Warning Signals
- Rule 35 : Sound Signals in Restricted Visibility
- Rule 36 : Signals to Attract Attention
- Rule 37 : Distress Signals
Part E - Exemptions
- Rule 38 : Exemptions