The latest version Revision 7 Change A incorporates changes made since the release of Revision 7. The editors state: “With this change, we updated technical information, provided clearer guidance, and corrected errors that were identified within Revision 7.” For many decades the US Navy Diving Manual has been the ultimate reference source for the diver. Potential readers may feel challenged by the sheer size of the work. At just under 1000 A4 pages this manual is unsurpassed in technical detail and depth. As the ultimate diving reference work the book contains everything you ever wanted to know about diving and many aspects that you could never imagine! The manual is however surprisingly easy to read and is composed of five individual volumes. The volumes are as follows:- Volume 1: Diving Principles and Policies. Volume 2: Air Diving Operations. Volume 3: Mixed Gas Surface Supplied Diving Operations. Volume 4: Closed Circuit and Semiclosed Circuit Diving Operations. Volume 5: Diving Medicine and Recompression Chamber Operations. Each section has been extensively researched and is widely regarded as the technical standard for diving information and procedures. The manual is easily referenced and used internationally by recreational, commercial, and military divers because of its authoritative and approved procedures. This 7th Revision Change A contains the most up to date decompression tables, and techniques for avoiding decompression sickness. The Manual is once again available in two distinct formats a Casebound version and a Looseleaf version held in a Binder.