SI 2021/812. The Merchant Shipping (Prevention of Pollution from Noxious Liquid Substances in Bulk and Prevention of Oil Pollution) (Amendment) Regulations 2021 Comes into force 3rd August. This regulation amends SI 2018/68 The Merchant Shipping (Prevention of Pollution from Noxious Liquid Substances in Bulk) Regulations 2018, principally changes to definitions and to the requirements on offshore support vessels, and SI 2019/42 The Merchant Shipping (Prevention of Oil Pollution) Regulations 2019, oil reference book.