The Recreational Dive Planner (or RDP) is a decompression table in which no-stop time under-water is calculated. The RDP was developed by DSAT

Diving Science and Technology

Diving Science and Technology is a corporate affiliate of the Professional Association of Diving Instructors and the developer of the Recreational Dive Planner. DSAT has held scientific workshops for diver safety and education....

 and was the first dive table developed exclusively for recreational, no stop diving. There are four types of RDPs: the original table version first introduced in 1988, The Wheel version, the original electronic version or eRDP introduced in 2005 and the latest electronic multi-level version or eRDPML introduced in 2008.

RDPs are almost always used in conjunction with dive log book

Dive log book

A dive log is used by a scuba 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...

s to record and monitor pressure depth and residual nitrogen levels.

The low price and convenience of many modern dive computer

Dive computer

A dive computer or decompression meter is a device used by a scuba diver to measure the time and depth of a dive so that a safe ascent profile can be calculated and displayed so that the diver can avoid decompression sickness.- Purpose :...

s mean that many recreational divers

Recreational diving

Recreational diving or sport diving is a type of diving that uses SCUBA equipment for the purpose of leisure and enjoyment. In some diving circles, the term "recreational diving" is used in contradistinction to "technical diving", a more demanding aspect of the sport which requires greater levels...

 only use tables such as the RDP for a short time during training before moving on to use a diving computer. Dive computers are also used as they calculate no-decompression limits based on the whole dive whereas the RDP is much more conservative and assumes a square profile dive where the diver spends the entire dive at one depth. Although this is much more conservative, dive computers provide much more dive time and therefore are the more popular option with most divers. Although even if you use a dive computer

Dive computer

A dive computer or decompression meter is a device used by a scuba diver to measure the time and depth of a dive so that a safe ascent profile can be calculated and displayed so that the diver can avoid decompression sickness.- Purpose :...

, you should still maintain a dive log book

Dive log book

A dive log is used by a scuba 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...

.