• in recreational diving, 100 feet/30 metres may be a deep dive
• in technical diving, 200 feet/60 metres  may be a deep dive
• in surface supplied diving, 330 feet/100 metres may be a deep dive

There are particular problems associated with deep dives:

• High gas consumption. Gas consumption is proportional to pressure - so at 165 feet/50 metres (6 bar) a diver breathes 6 times as much as on the surface (1 bar). Heavy physical exertion causes even more gas to be breathed.
• Increased nitrogen narcosis. This causes stress and inefficient thinking in the diver. When breathing air many divers find 130 feet/40 metres a safe maximum depth.
• The need to do decompression stops increases with depth. A diver at 6 metres may be able to dive for many hours without needing to do decompression stops. At depths greater than 130 feet/40 metres, a diver may have only a few minutes at the deepest part of the dive before decompression stops are needed. In the event of an emergency the diver cannot make an immediate ascent to the surface without risking decompression sickness. The diver needs a disciplined approach to planning and conducting dives and needs to carry extra gas for the decompression stops to reduce the risk of being unable to complete the stops.
• Drifting. If long decompression stops are carried out in a tidal current, the divers may drift away from their boat cover or a safe exit point on the shore.
• Increased breathing effort. Gas becomes denser and the effort required to breathe increases with depth.
• Increasing risk of carbon dioxide poisoning.
• Oxygen toxicity

There are several solutions to these problems:

• Carry larger volumes of breathing gas to compensate for the increased gas consumption and decompression stops. Rebreathers  are much more efficient consumers of gas than open circuit scuba.
• Use helium-based breathing gases such as trimix to reduce nitrogen narcosis and stay beyond the limits of oxygen toxicity.
• Diving shots, decompression trapeze and decompression buoys can help diver's return to their surface safety cover at the end of a dive.

A Journey To 1,000 feet/308 Metres - The Deepest Open Circuit Scuba Dive Ever - John Bennett was no stranger to the logistics, stress and hazards involved in pushing depth limits; on June 4, 2000 John made a solo dive to 838 feet/254 metres (that stood as the world record for depth on open circuit scuba in the open ocean until this dive) in the beautiful waters off Puerto Galera on the island of Mindoro in the Philippines.

Career Institute at Hall's Diving - State-of-the-art training in the latest recreational dive technology includes training in the use of rebreathers, submersibles, underwater communication systems, technical diving theory and deeper diving techniques.

Deep Diver Course by PADI -  The Deep Diver Specialty course offers you the opportunity of a lifetime - going deep to see thing others can only dream about.

Deep Down Diving - "For The Tek Generation -The Rebreather Specialist's". Whatever your desire the Deep Down millennium site is the gateway to your Recreational and Technical Training for the 21st Century. We as the independent, premier professional diver training school in the Midlands offer a full range of Recreational & Technical diver training courses.

Deep Ocean Internal -  ABB Reakor GmbH ABB TRC Academy Studios Advanced American Divers Agner Marine Consult. American Divers American Pacific Marine Applied Research Lab AquaPlus Aquatic Science Army Corp of Eng. Artic Venture A/S EM.Z Svitzer Bert Instruments Brazilian.

Deep Sea Directory - The UK directory of professional angling, diving and commercial workboats, incorporating the top tackle shops, dive shops, diver training establishments and recommended accommodation, pubs and food outlets, serving water sports enthusiasts worldwide.

Deep Sea Diving Locker - Information for and about U.S. Navy deep sea divers.

Deep Sea Movies - Chimney Rat-Tail fish, 6357m deep. Feeding behavior of a rat-tail fish at a living Calyptogena bed, 6370m deep. Fresh fissure at the seaward slope of Japan Trench, 6200m deep. Manganese pavement at the seaward slope of Ryukyu Trough.

Divers Institute of Technology -  Founded in Seattle, Washington in 1968 after it was determined that there was a growing demand for commercial divers, construction technicians and support personnel.

Hazards of Diving Deep - German U-Boat U-869 lies in 230 feet of water, which is fully 100 feet deeper than the recommended maximum limit for recreational diving.

Ocean Deep-How Deep Can They Go - Deep water is inhospitable for human divers and other animals because it's cold and dark, and the weight of water overhead exerts intense pressure. Learn about the facts through illustration and pressure variables.

 

Home Page

Deep Diving Scuba Links (you are here)