LIFE PRESERVER UNIT 10/P25-30. The LPU 10/P (NSN 4220-00-850-8655) is a standard U.S. Air Force CO2 cartridge-activated life preserver assembly worn during flights over water, or during airdrops when water obstacles are near or on the intended DZ. The LPU 10/P has an adjustable harness and underarm inflation bladders. It is designed to keep the wearer’s head above water at weights up to 250 pounds for up to 10 minutes. The LPU 10/P must be maintained according to U.S. Air Force standards.25-31. During the descent, the jumper inflates the life preserver by discharging the attached CO2 cartridges. If necessary, the life preserver can be inflated by blowing air into the inflation valve hose. As their feet touch the water, in case of drag, the jumper activates one canopy release assembly by pulling out on the safety clip exposing the cable loops. The jumper sounds off with “RISER” when activating the canopy release assembly using one of the two methods, hand to shoulder or hand assist. They prepare to execute a PLF if the water is shallow. The jumper swims upstream or upwind away from the parachute to avoid becoming entangled and signals “ALL OK” to the recovery boat.CAUTIONIf the jumper signals anything but the “ALL OK” or does not signal, the boat crew will proceed to assist the jumper from the water.25-32. The LPU 10/P is worn under the parachute harness. The harness is worn so that the inflatable pockets are under the jumper’s arms. The manual inflating valves should be completely closed when donning the life vest. The shoulder and waist straps are then adjusted to ensure the inflation container is one hand width beneath the armpit and not constrained by the parachute harness