Dive log

A dive log is used by an underwater diver to record the details of their dives. The log may either be in a book, software, or web based. The log serves purposes both related to safety and personal records. Information in a log may contain such things as date, time and location, the profile of the dive, equipment used, air usage, above and below water conditions, including temperature, current, wind and waves, general comments, verification of buddy instructor or supervisor.

In case of a diving accident, it can provide valuable data regarding diver's previous experience, as well as the other factors that might have led to the accident itself.

Recreational divers are generally advised to keep a logbook as a record, while professional divers may be legally obliged to maintain a logbook which is up to date and complete in its records. The professional diver's logbook is a legal document and may be important for getting employment. The required content and formatting of the professional diver's logbook is generally specified by the registration authority, but may also be specified by an industry association such as the International Marine Contractors Association (IMCA).

Typical fields in a recreational diver's log book would be the following:

A more minimalistic log book for recreational divers who are only interested in keeping a record of their accumulated experience (total number of dives and total amount of hours underwater), could just contain the first point of the above list and the maximum depth of the dive.

A commercial diver's logbook may be considered a legal document, and may contain more information, both about the diver, and about each dive recorded. It is generally verified by the diving supervisor for each diving operation. It may include the following sections:

The record of each dive may contain:

Usually diving computer manufactures have their own software to view and analyze diving logs, but there are also open source versions. Subsurface is free open source dive log software started by Linus Torvalds, which is compatible with several makes of downloadable diving computer.

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