2. By derogation from the provisions of article 6.04:
(a) Passenger vessels providing a regular service and whose authorized maximum passenger capacity is not below a number prescribed by the competent authority, when proceeding downstream and wishing to call at a landing-stage on the side used by vessels proceeding upstream; and
(b) Towed convoys proceeding downstream which wish to keep close to a particular bank in order to turn upstream
have the right to ask vessels proceeding upstream to change the course left clear for them in accordance with article 6.04 above if that course does not suit them.
However, they may not so ask unless certain that their request can be safely met.
3. In such cases, the vessels or convoys proceeding downstream shall give the following signals in good time:
− If they wish to pass to port, one short blast;
− If they wish to pass to starboard, two short blasts and, in addition, the visual signals referred to in article 6.04, paragraph 4.
4. Vessels or convoys proceeding upstream shall then grant the request of those proceeding downstream and confirm the fact as follows:
- If they are to pass to port, by sounding one short blast and, in addition, removing the visual signals referred to in article 6.04, paragraph 4;
- If they are to pass to starboard, by sounding two short blasts and, in addition, displaying the visual signals referred to in article 6.04, paragraph 4.
5. As soon as it appears that the intentions of a vessel proceeding downstream may not have been understood by a vessel proceeding upstream, the vessel proceeding downstream shall repeat the sound signals referred to in paragraph 4 of this article.
6. If a vessel proceeding upstream sees that the course requested by one proceeding downstream is unsuitable and will cause a danger of collision, it shall sound a series of very short blasts. The steersmen shall then take all the steps required by the situation to obviate the danger.
7. Paragraphs 1 to 6 above shall not apply to small craft in relation to other vessels or to small craft meeting other small craft.