1. In reduced visibility, vessels and floating equipment stationary in or near the fairway outside harbours or places specially designated by the competent authorities for berthing, shall be on listening watch on the ship--ship channel. As soon as they hear by radiotelephone, of the approach of other vessels, or as soon and as long as they hear from an approaching vessel one of the signals prescribed in article 6.32, paragraph 4 or article 6.33, paragraph 1 (b), they shall indicate their position by radiotelephone or give sound signals as follows:
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2. The provisions of paragraph 1 above shall not apply to vessels in a pushed convoy other than the pusher. In the case of a side-by-side formation, they shall apply only to one vessel in the formation. In the case of a towed convoy, they shall apply only to the towing vessel and the last vessel in the convoy.
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