Technical Dive Training for Scientists at NURP's Caribbean Facility Gets Underway

Marine scientists at the NOAA's Undersea Research Program's (NURP) Center for the Caribbean, the Caribbean Marine Research Center (CMRC), are using the latest technical diving technology to explore deep tropical reefs and caves in the Bahamas to depths as great as 90 meters (300 feet). Marine environments at these depths are seldom observed because they are located at an intermediate depth, between those unattainable using air or nitrox gas mixes for scuba, and often passed up by remotely operated vehicles (ROV's) and submersibles which are capable of diving to depths of thousands of meters. By using trimix, a combination of nitrogen, oxygen and helium, it is possible for divers to descend to hundreds of feet without suffering from toxic partial pressures of oxygen (which increase with depth), and also reduces the effect of nitrogen narcosis.

In 2001, scientists logged over 3000 dives at CMRC, 11 of which were greater than 40 meters (130 feet). In May 2002, CMRC successfully hosted its first technical diving and trimix dive training course on Lee Stocking Island in the Bahamas. CMRC Diving Safety Officer and International Association of Nitrox and Technical Divers (IANTD) instructor Brian Kakuk collaborated with Michael Lombardi (Project Dive Officer, Applied Subsea Technologies), Dr. Michael Lesser (University of New Hampshire), and Dr. Marc Slattery (The University of Mississippi) to create a deep diving program in support of scientific research and to establish CMRC as leader in deep-reef research dive training. During the 8-day trimix course, five divers logged 850 minutes bottom time at an average depth of 53 meters (range = 30-81 meters; 175 feet, range = 100-267 feet). Total accumulated runtime, which includes bottom time and decompression stops, was over 3000 minutes. After the divers completed the trimix and technical diving certification courses, four working dives were completed by 2 of the divers for a total of 60 minutes bottom time to depths up to 93 meters (308 feet), and over 400 minutes total runtime. Topside support for the two working trimix divers included one standby trimix diver, two support divers, and two dive vessel operators, as required by the IANTD operations manual, CMRC's proposed manual for decompression diving. In addition to on site support, all CMRC staff were briefed on emergency protocol and evacuation procedures.

Marine scientists working on a transect line in order to collect sponge and water samples on a depth contour near Lee Stocking Island, Bahamas (approx. depth 60 m/200 ft).

Research divers at their final decompression stop at 20 ft, after a 15 min bottom time at 300 ft using trimix gas.

The NURP Center at the CMRC and the University of North Carolina at Wilmington are among the few research facilities in the world using technical diving techniques and trimix to obtain scientific data on deep water habitats. Little information is known about the organisms found at these depths. However, using this advanced diving technology, Dr. Lesser is able to expand the scope of his research to deep reefs by using in situ methodology to compare phenotypic plasticity of deep water sponges found along a depth gradient down to 90 meters (300 feet) with sponges found at shallower depths. Use of trimix will supplement Dr. Slattery's investigation of marine cave fauna, specifically sponge diversity, and promote further exploration and discovery of the biomedical potential of natural cave sponge products.

Utilizing the latest dive technology, CMRC plans to create standards for deep water scientific diving and to become a leader in technical dive training for scientific application. As a technical dive training facility, CMRC plans to train scientists in the latest technical diving techniques available such as trimix and rebreathers, and become an instructor training center for diving safety officers from other organizations. By incorporating technical diving into the scientific diving program at CMRC, scientists will have the capability to study and explore deep marine environments rarely observed first hand.