Narrow channels
(A). A vessel proceeding along the course of a narrow channel or fairway shall keep as near to the outer limit of the channel or fairway which lies on her starboard side as is safe and practicable.
(B). A vessel of less than 20 metres in length or a sailing vessel shall not impede the passage of a vessel which can safely navigate only within a narrow channel or fairway.
(C). A vessel engaged in fishing shall not impede the passage of any other vessel navigating within a narrow channel or fairway.
(D). A vessel shall not cross a narrow channel or fairway if such crossing impedes the passage of a vessel which can safely navigate only within such channel or fairway. The latter vessel may use the sound signal prescribed in Rule 34(d) if in doubt as to the intention of the crossing vessel.
Note: Rule 34(d)
Sound: At least 5 short and rapid blasts on the whistle.
Note: Rule 34(d)
Light: At least 5 short and rapid flashes.
(E)
(i). In a narrow channel or fairway when overtaking can take place only if the vessel to be overtaken has to take action to permit safe passing, the vessel intending to overtake shall indicate her intention by sounding the appropriate signal prescribed in Rule 34(c)(i). The vessel to be overtaken shall, if in agreement, sound the appropriate signal prescribed in Rule 34(c)(ii) and take steps to permit safe passing. If in doubt she may sound the signals prescribed in Rule 34(d).
Note: Rule 34(c)(i)
I intend to overtake you on your STBD SIDE: Two prolonged blasts followed by one short blast. (morse code: ‘G’)
Note: Rule 34(c)(i)
I intend to overtake you on your PORT SIDE: Two prolonged blasts followed by two short blasts. (morse code: ‘Z’)
Note: Rule 34(c)(ii)
The vessel to be overtaken shall, if in agreement: one prolonged, one short, one prolonged and one short blast. (morse code: ‘C’)
Note: Rule 34(d)
Sound: If in doubt she may sound the signals:
At least 5 short and rapid blasts on the whistle.
(E)
(ii). This Rule does not relieve the overtaking vessel of her obligation under Rule 13.
(F). A vessel nearing a bend or an area of a narrow channel or fairway where other vessels may be obscured by an intervening obstruction shall navigate with particular alertness and caution and shall sound the appropriate signal prescribed in Rule 34(e).
Note: Rule 34(e)
(1) A vessel nearing a bend or an area of a channel or fairway where other vessels may be obscured by an intervening obstruction shall sound one prolonged blast.
Note: Rule 34(e)
Such signal shall be answered with a prolonged blast by any approaching vessel that may be within hearing around the bend or behind the intervening obstruction.
(G). Any vessel shall, if the circumstances of the case admit, avoid anchoring in a narrow channel.