Decompression (diving) but in later experiments signs of what was later to become known as decompression sickness were observed. Later, when technological advances allowed the use of pressurization of mines and caissons to exclude water ingress, miners were observed to present symptoms of what would become known as caisson disease, compressed air illness, the bends, and decompression sickness. Once it was recognized that the symptoms were caused by gas bubbles, and that re-compression could relieve the symptoms, Paul Bert showed in 1878 that decompression sickness is caused by nitrogen bubbles released from tissues and blood during or after decompression, and showed the
Decompression practice The no decompression limit (NDL) or no stop time, is the interval that a diver may theoretically spend at a given depth without having to perform decompression stops. The NDL helps divers plan dives so that they can stay at a given depth and ascend without stopping while avoiding unacceptable risk of decompression sickness. The NDL is a theoretical time obtained by calculating inert gas uptake and release in the body, using a model such as the Bühlmann decompression algorithm. Although the science of calculating these limits has been refined over the last century, there is still much that is