Petroleum industry activities have progressed rapidly into water depths beyond the safe limitations on professional divers. Practical and physiological factors affecting diver health and safety are reviewed, and the problems and potential of extending safe diving to 1500 feet or more are considered. To extend safe diving capability deeper than 600 feet requires more research and development. Leaders in the field are encouraged to continue and perhaps accelerate diving research.
Until the last few decades, man's subsea diving depth has been limited to about 100 feet. Recently, commercial interests in the oceans, along with naval development, have been responsible for a rapid extension of depth. In particular, the offshore petroleum industry, which accounts for some 80 percent of commercial diving, has been rapidly moving to increasingly deeper water. Twenty years ago, offshore drilling and production was limited to water depths of approximately 50 feet. Today, production has been established in water depths of over 300 feet; exploratory drilling operations have moved to water 1300 feet deep, and a discovery has been made in about 1000 feet. (Fig. 1 indicates present maximum depths of different petroleum industry activities.) At the same time, diving is routinely conducted to depths of 300–500 feet, experimental dives have been conducted in the open sea to depths of over 600 feet, and simulated laboratory dives have been conducted to pressures equivalent to 1150 feet.
Oil operations will continue to extend to deeper water, and as this occurs, extension of man-in-the-sea's working depth capability will be necessary. This capability may be provided by divers if deep diving can be safely accomplished at reasonable cost. A number of medical and engineering developments are necessary if this is to occur. These challenges include the development of life support systems to supply the diver with properly controlled breathing mixtures, clothing to protect him from the cold subsea environment, and pressure chambers to allow him to be properly compressed and decompressed to and from the pressures encountered in the sea.
For these improvements in the safe and efficient use of divers to occur, it will require the use of the nation's best scientific talent in the fields of engineering, medicine, physiology, pharmacology, biochemistry, behavior science and computer science. To date, diving developments have been largely the concern of diving contractors, navies of the world, and several universities. But the operator who needs extended diving capability to help him exploit deepwater mineral resources should be aware of physiological problems and the requirements for their resolution.
The objectives of this paper are to describe the important deep-diving physiological concerns. At the same time, we hope to acquaint the user of diver services with the basic concerns of diving safety and thus prepare him to work with diving contractors to insure safe diving operations; we also hope to indicate to the offshore industries some fruitful areas for the best research use of money and talent.