There should be a requirement in the PSC & S Regulations for standard envelope curves, at least for level keel and trims by the stern and by the head of, say, 0.4% and 0.8% of the length of the ship. In view of the importance of this point, the Court considers that requirements should be imposed upon all existing ferries for the provision of such initial trim curves. These should be implemented within a short time to prevent operation at unsuitable (and possibly dangerous) trims and vertical centres of gravity. The Court also considers that all existing Stability Books for Ro-Ro passenger ferries should be reviewed in detail by the department. Furthermore, during the review of existing books they should be examined to see whether they provide adequate information for the assessment of safe loading in respect of factors such as the tabulation of vertical centres of gravity for cargo on all vehicle decks. A standardised vertical centre of gravity should be used for each type of vehicle.