1. On sections marked by the signs A.4 or A.4.1 (annex 7), passing and overtaking are prohibited. The prohibition referred to in the preceding sentence may be limited to vessels and convoys above a certain length or breadth; in such cases, the length or breadth is indicated on a rectangular white board fixed below the signs A.4 and A.4.1. In addition, the provisions of article 6.07, paragraph 1, apply by analogy.
2. If, in order to prevent any meeting, the competent authorities prescribe alternate one-way traffic:
- Prohibition of passage shall be indicated by a general prohibitory sign (A.1, annex 7);
- Authorization of passage shall be indicated by a general “entry permitted” sign (E.1, annex 7).
Depending on local circumstances, warning of the sign prohibiting passage may be given by the mandatory sign B.8 (annex 7) used as an advance sign.