Dr. Christian J. Lambertsen, who as a medical student in 1939 invented a revolutionary underwater breathing system used by the military in World War II and who later helped coin the popular acronym to describe his device and others like it — scuba — died of renal failure Feb. 11 at his home in Newtown Square, Pa. He was 93.
Lambertsen was a longtime professor at his alma mater, the University of Pennsylvania School of Medicine. He was an expert on respiratory physiology and diving-related ailments.
His 1939 invention, the Lambert sen Amphibious Respirator Unit, or LARU, is considered a forerunner of the scuba technology used today.
In 1952, Lambertsen and a colleague wrote a paper for the National Academy of Sciences describing his “Self Contained Underwater Breathing Apparatus,” which they shortened to scuba.
Before World War II, military divers wore clunky metal helmets that pumped breathable air through hoses tethered to boats on the water’s surface.
Lambertsen’s LARU let divers swim freely and stealthily. It used pure oxygen and was a closed system. Equipped with a carbon dioxide filter, it enabled the diver to re-breathe the air he exhaled while underwater, which made the system bubbleless.
After the Navy rejected his device at first, Lambertsen demonstrated the LARU in the swimming pool of the Shoreham Hotel in Washington in 1942 to the Office of Strategic Services, the World War II predecessor of the CIA.
Not only was the OSS impressed with the invention, the nascent spy agency saw great potential in the young medical student, who was an experienced diver.
Lambertsen joined the Army Medical Corps and, later, the OSS.
