There are two types of diving:
Apnea diving or snorkeling: The term apnea refers the voluntary suspension of breathing. Therefore, diving in apnea is when we submerge with the air that we previously take in at the surface.
Diving with bottles: this type of diving is carried out with equipment that allows us to breathe under water: air, oxygen, or special mixture of gases.
When people do not observe the necessary preparations, when technical problems arise or when the safety procedures for diving are not correctly followed, accidents can happen that cause various types of diving sicknesses. For the treatment of some of these, a hyperbaric chamber is used.
Many of these diving sicknesses are treated without using the hyperbaric chamber, but they should always be treated by qualified medical personnel and under appropriate hospital conditions.