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Chapter 10- Diving Techniques and Deeper Diving Diving Techniques and Deeper Diving 243 Insufficient Experience Insufficient experience is a major factor in diver distress situations for deep diving. Whether the insufficient experience is due to lack of mastery of basic skills or infrequent diving activity, this problem manifests itself in overweighting, lack of buoyancy control, lack of equipment familiarity, improper use of dive tables or dive computers, and unsafe diving practices. These most common hazards can be minimized by your participation in ongoing continuing education programs and organized diving activities. Increased Stress There is an increased amount of stress on divers during deep dives. Increased stress build-up can result in both mental and perceptual narrowing. These situations create a task-loading, which may include some combination of the following: • Potential lack of familiarity with dive environment, dive buddy, and/or diving equipment. • If using tables, there is a more critical time and depth limit. • Effects of narcosis. • Less available light. • Extra tasks, like photography. • Anxiety about air consumption. • Unexpected currents/changing weather. • Use of more sophisticated equipment. • Greater buoyancy fluctuation. This task loading can be minimized with proper planning and participation in a comprehensive deep diving course, which intentionally and gradually exposes you to greater depths, more refined procedures, and increased task loads. Another related hazard which results from a combination of task loading and possibly some narcosis, is a lowering of diver awareness levels. THE DEEP DIVE Once the dive has been planned, equipment is assembled, and the briefing is completed, the dive may begin. Since each dive site and dive may be somewhat unique, it is difficult to prepare a precise diving procedure that can be applied to all dives. General procedures that apply to any dive will be discussed. Assemble and Check Equipment All equipment should be laid out and checked prior to donning diving suits. The dive support station is assembled. If any equipment is missing or malfunctioning, corrections must be made. In some cases, a diver may be disqualified for the dive because of equipment problems or lack of sufficient air supply. Checklists are a handy way of making sure nothing is missed. Suit Up Suiting up should be delayed until the briefing has been completed and all equipment is readied. Divers should avoid long surface exposures in suits and equipment. Divers should coordinate suiting up and donning scuba so that all divers can be suited up and then enter the water at one time. A complete buddy check is then conducted. Final Briefing Just before the divers enter the water the lead diver or supervisor will repeat the key points of the dive plan, including air pressure, depth and time limits, and visually check each diver. This final briefing should be concise, but not rushed. Using a briefing card or a checklist is also a good practice. Dive Support Station Some divers will combine the surface float, descent- ascent line, bottom weight, emergency air supply system, and stop weights into a single unit (the dive support station) to facilitate equipment management and deployment. For example, when making a deep dive from shore in a quarry or lake, the descent-ascent line (stored by stuffing into a rope bag) and bottom weight may be secured to the surface float. The emergency air supply system and stop


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