1. Every radiotelephone installation carried on board a vessel shall conform to the Regional Arrangement concerning the Radiotelephone Service on Inland Waterways, and shall be used in accordance with the provisions of this Arrangement. Details of these provisions are provided in the radiotelephony guide for inland navigation.
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4. Each vessel equipped with a radiotelephone installation shall make reports on the channel allocated to the ship-to-ship network before entering blind sections, narrow channels or bridge openings and the sections determined by the competent authorities.
5. Sign B.11 (annex 7) shall indicate that the competent authority requires the use of radiotelephone communications.