The Recreational Dive Planner (or RDP) is a
decompression table in which no-stop time underwater is calculated.
The RDP was developed by
DSAT and was the first dive table developed exclusively for no-stop recreational diving.
There are four types of RDPs: the original table version first introduced in 1988 along with a
circular slide rule
The slide rule is a mechanical analog computer which is used primarily for multiplication and division, and for functions such as exponents, roots, logarithms, and trigonometry. It is not typically designed for addition or subtraction, which i ...
version called The Wheel, followed by the eRDP, an electronic version introduced in 2005 and the eRDPML, an electronic multi-level version introduced in 2008.
RDPs are almost always used in conjunction with
dive log books to record and monitor pressure depth and residual nitrogen levels.
The low price and convenience of many modern
dive computer
A dive computer, personal decompression computer or decompression meter is a device used by an underwater diver to measure the elapsed time and depth during a dive and use this data to calculate and display an ascent profile which according to th ...
s mean that many
recreational divers 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.
References
Decompression algorithms
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