Some Implications of the New Collision Regulations. In Rule 6 the discussion of what constitutes a ‘safe speed’, paragraph (b) (iv) states that ‘the possibility that small vessels, ice and other floating objects may not be detected by radar at an adequate distance’ is one of the factors which should be taken into account. Leaving aside the question of how the new term ‘safe speed’ differs from the old ‘moderate speed’ this is not a fundamental change, although the provision appears in a different place and with different emphasis in the new rules. It is a provision which ought to be treated more conscientiously by many mariners since, for example, it has been observed that the mean speed of ships through the Dover Strait is about 12 knots and that this does not appear to be significantly reduced when visibility decreases.