Foreword The 2012 edition of the Rules for Building and Classing Underwater Vehicles@ Systems and Hyperbaric Facilities incorporates all Rule Changes and Corrigenda items since 2010 and has been reorganized to move the requirements for remotely operated vehicles@ handling systems@ and dive control stations from Appendices to Rules Sections. Requirements for lock-out submersibles are added. Also@ some requirements have been revised for clarity and others to more accurately reflect actual practice. ? Sections 1 through 10 provide the general requirements that are applicable to all categories of underwater vehicles@ systems and hyperbaric facilities. ? Section 11 provides the specific requirements that are applicable to manned submersibles. ? Section 12 provides the specific requirements that are applicable to lock-out submersibles. ? Section 13 provides the specific requirements that are applicable to diving systems. ? Section 14 provides the specific requirements that are applicable to remotely operated vehicles. ? Section 15 provides the specific requirements that are applicable to handling systems. ? Section 16 provides the specific requirements that are applicable to dive control stations. ? Section 17 provides the requirements for surveys after construction. ? Appendix 1 provides relevant excerpts from IMO Res. A.831 (19) Code of Safety for Diving Systems regarding diving bell emergency locating devices ? Appendix 2 provides a cross-reference table between the 2010 and 2012 Rules. The effective date of each technical change is shown in parentheses at the end of the subsection/paragraph titles within the text of each Section. Unless a particular date and month are shown@ the effective date is 1 January of the year shown.