In the event of water-related emergencies (such as an emergency landing in a lake or the ocean), life jackets and flotation devices serve as safety equipment to improve survival chances.
Passengers can slip the life jacket over their heads and secure it to their body in order to keep their upper body above the water. When used as a flotation device, the passenger seat cushion can also assist a passenger in keeping his head above water as he holds onto the cushion.
During the preflight safety briefing delivered by the flight attendants and/or airplane personnel, the location of life preservers are specified for aircraft flying over water. Life jackets may be stowed under the seat or in the armrest; the passenger seat cushion may be detached to use as a personal flotation device.
