The square-root principle in the calculation of one-stage (no-stop) decompression tables.


A square-root formulation, square-root time x excursion depth = k, developed at the Royal Navy Physiologic Laboratory (RNPL) predicts the safe duration of air excursions at 1 ATA for periods up to 6 h (air) and up to 3 h (heliox atmosphere). At pressures above 1 ATA, the value of k was initially considered to be proportional to Haldanian multiples of ATA and not to the square-root ATA used in this paper. Excursions of infinite (infinity) duration can also be predicted from a square-root formula derived from the systematic heliox saturation excursions conducted at the Experimental Diving Unit in which net excursion depth = k square-root P abs. This paper presents a broad spectrum format that extends the square-root principle: 1) to values of k above 1 ATA in the RNPL formula and 2) to excursions for (infinity) time from habitat depths to 820 ft; and 3) which demonstrates a relationship between fractional time excursions and excursions for infinite periods of time. Application of the generalization that net excursion depths are proportional to square-root P abs would reduce to a minimum the number of programmed test dives and would, in addition, allow such dives to be conducted at relatively low pressures, with only occasional validating tests at deep depths.

Cite this paper

@article{Behnke1979TheSP, title={The square-root principle in the calculation of one-stage (no-stop) decompression tables.}, author={Albert R Behnke}, journal={Undersea biomedical research}, year={1979}, volume={6 4}, pages={357-65} }