Buoyancy devices

flotation device; airtight hollow structures that is buoyant in water

thumb|Lifebuoy with emergency light on a cruise ship thumb|A lifebuoy floating on water

classic science experiment demonstrating the Archimedes' principle and the ideal gas law

objects designed to help a wearer float in water

system of boxes to rise a ship in the water

compartment within a boat, ship or other floating structure