AB: American Bureau of Shipping; BV: Bureau Veritas; GL: Germanischer Lloyd; LR: Lloyd’s Register; NV: Det Norske Veritas; RI: Registro Italiano Navale; NK: Nippon Kaiji Kyokai. These are the classification societies authorised by the MCA to act as Assigning Authorities for load lines and freeboards. “DT” are the letters used by the Department for Transport (MCA) on the loadline of a modern unclassed UK ship.