▁preceding ▁ 2 4 ‑ hour ▁period ▁are ▁given ▁on ▁the ▁US ▁Navy ▁D iving ▁Man ual ▁Table ▁ 9 . 6 , ▁both ▁for ▁asc ents ▁to ▁specified ▁alt itudes , ▁and ▁for ▁commercial ▁fl ights ▁in ▁aircraft ▁nomin ally ▁press ur ized ▁to ▁ 8 0 0 0   ft . ▁ ▁The ▁first ▁D AN ▁flying ▁after ▁div ing ▁work shop ▁in ▁ 1 9 8 9 ▁cons ensus ▁gu idel ines ▁recommended : ▁ ▁wait ▁for ▁ 1 2 ▁hours ▁before ▁flying ▁after ▁up ▁to ▁two ▁hours ▁of ▁no - stop ▁div ing ▁within ▁the ▁previous ▁ 4 8 ▁hours ; ▁ ▁wait ▁for ▁ 2 4 ▁hours ▁before ▁flying ▁after ▁multi - day , ▁un limited ▁no - stop ▁div ing ; ▁ ▁wait ▁for ▁ 2 4 – 4 8 ▁hours ▁before ▁flying ▁after ▁div es ▁that ▁required ▁decom pression ▁stops ; ▁ ▁do ▁not ▁fly ▁with ▁D CS ▁sympt oms ▁unless ▁necessary ▁to ▁obtain ▁hyper bar ic ▁treatment . ▁ ▁D AN ▁later ▁proposed ▁a ▁simpler ▁ 2 4 - hour ▁wait ▁after ▁any ▁and ▁all ▁recre ational ▁div ing , ▁but ▁there ▁were ▁ob jections ▁on ▁the ▁grounds ▁that ▁such ▁a ▁long ▁delay ▁would ▁result ▁in ▁lost ▁business ▁for ▁island ▁div ing ▁resort s ▁and ▁the ▁ris ks ▁of ▁D CS ▁when ▁flying ▁after ▁div ing ▁were ▁too ▁low ▁to ▁war rant ▁this ▁blank et ▁rest raint . ▁ ▁The ▁D AN ▁F lying ▁after ▁D iving ▁work shop ▁of ▁ 2 0 0 2