Example
How deep can a diver go down in ocean water (when density = 64 lbm/ft3) without damaging his watch, that will withstand an absolute pressure of 80 psia? (P = density • height)
Solution
Suppose, Patm = 14.7 psia
Pabs =Patm +Pgauge
80 psia = 14.7 + Pgauge
Pgauge = (80 - 14.7) = 65.3 psig
Pgauge = density • height = ρH
(65.3)(144 in2/ft2) = (64 lbm/ft3) H
H = (65.3)(144)/(64)
H = 146.9 ft