Throughout the evolution of diving, from the earliest breath-holding sponge diver
to the modern saturation diver, the basic reasons for diving have not changed.
National defense, commerce, and science continue to provide the underlying basis
for the development of diving. What has changed and continues to change radically
is diving technology.
Each person who prepares for a dive has the opportunity and obligation to take
along the knowledge of his or her predecessors that was gained through difficult
and dangerous experience. The modern diver must have a broad understanding of
the physical properties of the undersea environment and a detailed knowledge of
his or her own physiology and how it is affected by the environment. Divers must
learn to adapt to environmental conditions to successfully carry out their missions.
Much of the diver’s practical education will come from experience. However,
before a diver can gain this experience, he or she must build a basic foundation
from certain principles of physics, chemistry and physiology and must understand
the application of these principles to the profession of diving.