Decompression Tables

Question 0

Total decompression time - TDT

Answer 0

Computed from leaving the bottom to reaching the surface.

Question 1

Bottom time - total bottom time

Answer 1

The total elapsed time from departing the surface to the time you begin ascent from the bottom or the greatest depth attained

Question 2

Total time of dive - TTD

Answer 2

Computed from leaving the surface to reaching the surface.

Question 3

Repetitive group designator - REPET

Answer 3

Letter which is used to relate directly to the amount of residual nitrogen remaining in a diver’s body.

Question 4

Surface interval -SI

Answer 4

Amount of time, expressed as “hours:minutes”, elapsed from the end of one dive to the beginning of the next.

Question 5

Residual nitrogen time - RNT

Answer 5

The amount of excess nitrogen, represented in minutes, from a previous dive.

Question 6

Decompression schedule

Answer 6

A specific decompression procedure for a given combination of depth and bottom time as listed in the decompression table. Normally indicated as fsw/minutes.

Question 7

Equivalent single dive bottom time

Answer 7

The combination of RNT from a previous dive plus the actual bottom time of the current dive.

Question 8

Decompression stops

Answer 8

Necessary when a large quantity of nitrogen has been accumulated in the body.

Waiting periods during decompression.

Stops allow more time for nitrogen to leave tissue.