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Although the double hull requirement was adopted in 1992, following the Erika incident off the coast of France in December 1999, IMO Member States discussed proposals for accelerating the phase-out of single hull tankers. As a result, in April 2001, IMO adopted a revised phase-out schedule for single hull tankers, which entered into force on 1 September 2003 (the 2001 amendments to MARPOL). The revised requirements set out a stricter timetable for the phasing-out of single-hull tankers.