, ▁which ▁is ▁not ▁predicted ▁by ▁the ▁existing ▁b ubble ▁model . ▁ ▁A ▁controlled ▁compar ative ▁study ▁by ▁the ▁Navy ▁Ex perimental ▁D iving ▁Unit ▁in ▁the ▁N ED U ▁Ocean ▁Sim ulation ▁Fac ility ▁wet - pot ▁comparing ▁the ▁V VAL 1 8 ▁Th al mann ▁Algorithm ▁with ▁a ▁deep ▁stop ▁profile ▁suggests ▁that ▁the ▁deep ▁stops ▁schedule ▁had ▁a ▁greater ▁risk ▁of ▁D CS ▁than ▁the ▁matched ▁( same ▁total ▁stop ▁time ) ▁conventional ▁schedule . ▁The ▁proposed ▁explanation ▁was ▁that ▁slower ▁gas ▁was h out ▁or ▁continued ▁gas ▁u pt ake ▁offset ▁benefits ▁of ▁reduced ▁b ubble ▁growth ▁at ▁deep ▁stops . ▁ ▁Profile ▁determined ▁intermediate ▁stops ▁P DIS s ▁are ▁intermediate ▁stops ▁at ▁a ▁depth ▁above ▁the ▁depth ▁at ▁which ▁the ▁leading ▁compart ment ▁for ▁the ▁decom pression ▁calculation ▁switch es ▁from ▁on g ass ing ▁to ▁off g ass ing ▁and ▁below ▁the ▁depth ▁of ▁the ▁first ▁oblig atory ▁decom pression ▁stop , ▁( or ▁the ▁surface , ▁on ▁a ▁no - de com pression ▁d ive ). ▁The ▁ambient ▁pressure ▁at ▁that ▁depth ▁is ▁low ▁enough ▁to ▁ensure ▁that ▁the ▁t issues ▁are ▁mostly ▁off g ass ing ▁in ert ▁gas , ▁although ▁under ▁a ▁very ▁small ▁pressure ▁gradient . ▁This ▁combination ▁is ▁expected ▁to ▁in hib it ▁b ubble ▁growth . ▁The ▁leading ▁compart ment ▁is ▁generally ▁not ▁the ▁fast est ▁compart ment ▁except ▁in ▁very ▁short ▁div es , ▁for ▁which ▁this ▁model ▁does ▁not ▁require ▁an ▁intermediate ▁stop . ▁The ▁ 8 ▁compart