Introduction. Training Curriculum

Transcription

1 THE TRANSITION FROM SCUBA TO WAYSTATION SURFACE-SUPPLIED DIVING Michael A. Lang Smithsonian Institution Office of the Under Secretary for Science PO Box MRC 415 Washington, DC U.S.A. Introduction From , the NOAA/USC Interim Science Program was established at the USC Catalina Marine Science Center in anticipation of the deployment at Catalina Island of the saturation habitat now known as Aquarius. A Waystation and Tether Training Program was developed by NURP Science Program Director Bob Given, Hyperbaric Chamber Director Andy Pilmanis, and Operations Director Jack Baldelli. Two 4-day missions (130 fsw max. depth) were performed by Peter Haaker (California Department of Fish and Game) and Michael Lang (San Diego State University) investigating white abalone and California octopus. The training program s duration was two days long, more than adequate to acquire the necessary skills for the operational aspects of this waystation surface-supplied diving system. Training Curriculum 1. Introduction 2. System and Equipment a. Air supply (sources, regulator, mask and helmets, umbilical) b. Communications c. Pneumofathometer d. Buoyancy control e. Thermal protection f. Weight system g. Knife 3. Regulations a. Qualifications b. Rules 4. Operations a. Dive team responsibilities (diver, tender, stand-by diver, shoreside support) b. Pre-dive preparations (mask, helmet, dressing) c. The dive (communications, dive plan) d. Post-dive 197

2 e. Emergency procedures (loss of verbal communication, air supply failure, fouling, blow-up 5. Training a. Instruction outline b. Training schedule 6. Exposure dives a. Requirements b. The dive 7. Appendices: requirements for primary and secondary breathing gases, bail-out, umbilical hose, line pull signals The Waystation System The waystation system (Fig. 1a and b) is a mobile unit consisting of an anchor plate, an open bell with skirt, and a surface support barge (Fig. 2a and b), positioned above it. Umibilicals are stored on the outisde of the bell, as are oxygen cylinders used for decompression. 198

3 Figure 1. Waystation system. Topside Support Hot water and compressed air were supplied from a surface-support barge directly above the waystation, anchored to the bottom (110 fsw) with a 1,000 lb weight. Support boats ferried staff and supplies from shore and stood by in case of diver emergencies. This particular program was supported through the immediate proximity of the Catalina Hyperbaric Chamber. 199

4 Figure 2. Support barge with hot water and air supply. The Crew Chief The success of this program and its participants is attributed to a large degree to the commercial diving experience and qualifications of the all-important crew chief (Fig. 3). It remains an example of operational efficiency and scientific productivity through the application of commercial diving technology to the scientific community. The control of the dive was performed topside. The diver to surface communications system allowed the scientific diver to focus on the research task and leave all operational aspects to the crew chief such as gas supply, bottom time and depth recordings, decompression stops, oxygen breathing, equipment performance, and hot water supply. 200

5 Figure 3. Jack Baldelli (Crew Chief) controlled the dive: hot water supply, breathing gases, communications, and decompression. The Transition from Scuba to Surface-Supplied Diving Perhaps the most revealing aspect of the transition from scuba to surface-supplied diving was the ease by which it was accomplished, under this training program and in this particular environment. With an experienced crew chief topside and using first-rate surface-supplied equipment, those of us whose experience base was mainly in opencircuit, compressed air scuba in temperate California kelp beds experienced several advantages. Heretofore having to rely on dry suits or ¾ wetsuits we now had the luxury of a simple 3 mm wetsuit with hot water supplied through a hose ending in a T on the chest, inserted through the wetsuit collar. So effective was this system that no gloves were needed as the hot water flooded through the suit and created a visible warm water envelope flowing out through the sleeves around the hands. The need for a heavy weight belt was obviated, providing a lightweight sense of freedom of movement. The use of a horse-collar front buoyancy compensator (bc) was mandated and this created for some of us a source of distraction for several reasons: the front side of the diver was encumbered, and the buoyancy mechanics of a front bc have a tendency to try to invert the diver while in a horizontal swimming position, our orientation for the majority of the dive. A back-mount bc or wings that provide buoyancy more similar to that of a hot air balloon concept with the negative ballast, diver and gear, positioned below the positive buoyancy component is preferable. A bail-out system with cylinder was harnessed to the diver s back. The management of the umbilical, in this particular environment devoid of overhead obstructions and currents in Big Fisherman s Cove, was a non-issue. It is expected that a similar experience would be had descending along a coral reef wall on a multi-level dive for deep science projects. The exploration of the bottom habitat for the two cryptic target species, white abalone (Haliotis sorenseni) and California two-spot octopus (Octopus bimaculatus), did not require extensive horizontal excursions. Conclusion 201

6 For this project in this specific environment, the waystation surface-supplied diving method worked flawlessly. The 2-day training session for experienced scientific divers was sufficient to allow for an immediate focus on the scientific objectives. Safety and support were outstanding and the importance of an experienced crew chief cannot be overemphasized. This type of system allows for significant flexibility and can be readily moved to sites of scientific interest. Additional References Davis, G.E., P.L. Haaker, D.V. Richards The perilous condition of white abalone, Haliotis sorenseni, Bartsch, Journal of Shellfish Research 17(3): Lang, M.A. and F.G. Hochberg. (eds.) Proceedings of the Workshop on Fishery and Market Potential of Octopus in California. Smithsonian Institution. 192 pp. 202