(A). Nothing in these Rules shall exonerate any vessel, or the owner, master or crew thereof, from the consequences of any neglect to comply with these Rules or of the neglect of any precaution which may be required by the ordinary practice of seamen, or by the special circumstances of the case.
Note: Examples of precautions which may be required by the ordinary practice of seamen or by special circumstance, are the following:
- A vessel under way would be expected to keep clear of a vessel at anchor as a matter of seamanship.
- A vessel under way and stopped must not rely on other vessels keeping out of her way, unless she is not under command and is displaying the appropriate signals.
- A vessel about to anchor, she must do so without put other vessels in danger which may be navigating close by.
- A vessel must not anchor too close to other anchored vessels. Sufficient cable must be put out according to circumstances and a second anchor should be used if necessary.
- In dense fog a vessel without operational radar may not be justified in being under way at all but should anchor if it is safe and practicable for her to do so.
- When two vessels are approaching one another at a difficult bend in a tidal river it has been held to be duty of the one having the tide against her to wait until the other has passed.
(B). In construing and complying with these 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.
Note: Examples of departure from these Rules necessary to avoid immediate danger, are the following:
- Dangers of navigation and collision: special circumstances allow you to deviate from the Rules, if necessary, to avoid immediate danger, i.e. dangers of navigation or dangers of collision. For instance, a power-driven vessel (A) meeting another power-driven vessel (B) end on may be unable to alter her course to starboard, as directed by Rule 14, owing to the presence of shallow water close by to starboard or to the fact that a third vessel is overtaking her on her starboard side.
- Special circumstances and immediate danger: This Rule does not give any vessel the right to take action contrary to the Regulations whenever it is considered to be advantageous to do so. A departure is only permitted when there are special circumstances and there is immediate danger. Both conditions must apply. The departure must be of such a nature as to avoid the danger which threatens.
- Squadrons or convoys: The Mariner’s Handbook draws the attention of mariners to the dangers which may be caused by single vessels (A) attempting to pass ahead of, or through a squadron of warships or merchant vessels in convoy. Single vessels (A) are advised to take early measures to keep out of the way, and the vessels in the squadron or convoy are warned to keep a careful watch and be ready to take such actions as will best aid to avert collision. Mariners are expected to take into account the cautions and recommendations given in Notices to Mariners and other official publications but if a vessel in a formation or convoy is approached by a single vessel so as to involve risk of collision the Steering and Sailing Rules must be complied with. Action taken in accordance with the advice to avoid a squadron or convoy on the port bow would not be departure from the Rules if executed at a long range before risk of collision begins to apply.