The most famous chamber and the most used chamber was that of Dr Cunningham in Kansas City during the 192os. Cunningham first used the chamber to treat the victims of the Spanish influenza epidemic which spread across the USA during the end of the First World War. Cunningham had observed that mortality from this disease was higher in the areas of elevated land. He believed therefore that a barometric factor was involved. He claimed that there was major improvements in the patients he treated.
One night, however, a mechanical failure occurred and it resulted in a complete loss of compression and all of his patients died. This was a lesson for Cunningham but his enthusiasm for hyperbaric air continued and he started treating diseases such as syphilis, hypertension, diabetes and cancer.
In 1928 Cleveland Cunningham built the largest chamber ever, it was five stories high and 64 feet in diameter. Each floor had 12 bedrooms and it was built like a hotel. At that time it was the only functioning hyperbaric chamber in the world.
The Cunningham chamber was dismantled for scrap in 1937 after Cunningham repeatedly refused to present evidence of the medical uses of his chamber. This brought around a temporary end to the era of Hyperbaric Oxygen therapy for medical uses.