Chapter 1- Diving Equipment Diving Equipment 25 Rubber Seal Actuator Button Buoyancy compensators require more than casual care. Internal rinsing is critical, especially for ocean diving, as sand and dried salt can cause wear. Prevent water from entering the bladder while diving by orienting the mouthpiece of the deflation valve downward when the valve is open. The BC can still be deflated by raising the deflator valve above the BC, but the inverted mouthpiece will act as an air trap to exclude water. Your buoyancy compensator should be inflated for storage. The storage area should be temperature regulated and free from smog and ozone. Many divers store their expensive diving equipment in a garage, which is not a good fumefree environment for the materials used in the equipment. Some BC models are designed for easy switching from single to double cylinders. Some of these have strong backplates and harnesses that allow for adjustment to accommodate dry suit inflator hoses, quick release buckles, and D-rings. There are models available with double, redundant bladders. There are also BCs with integrated weight systems that eliminate the use of the standard weight belt. The weights are held in pockets and can be released by pulling a rip-cord type handle. One disadvantage of these systems is that it increases the weight of handling the entire cylinder/BC/weight system. Another is that a dive leader cannot readily spot overweighted divers. Weight placement on a diver can be adjusted by using a weight trim system. This harness weight system allows for adjustment of weights up and down, and forward and backward, for the most efficient trim in the water. DRY SUITS Dry suits are the most efficient way for a scuba diver to remain comfortable in cold water (figure 1-29). The most popular dry suits on the market today are made from a variety of waterproof materials, including vulcanized rubber, waterproofed nylon, and compressed neoprene. The suits seal at the neck and wrists and are equipped with waterproof zippers for entry. Low pressure inflator mechanisms prevent suit squeeze, and suit exhaust valves allow air to escape upon ascent. The theory behind these suits is that they form a waterproof barrier but offer little or no insulation themselves. To be warm you must wear some type of thermal insulation underneath the suits. These suits also have no inherent buoyancy. Compressed neoprene suits can stretch, so the suit can be well tailored to the diver’s body. The seams of these suits are glued and stitched. On-site repairs to this material, when punctured, can be difficult. Waterproof laminated nylons have almost no stretch. Suits made from these materials must be cut quite loosely to allow you to dress into them without difficulty. This creates some added volume in the suit which may increase your weight requirements. You can do some repairs to these types of suits yourself but major repairs must be handled by the manufacturer. Vulcanized rubber dry suits should be manufactured from a combination of natural and synthetic Inflator Air Inlet Spring Water Purge Holes Air to Vest Valve and Seat FIGURE 1-27. BC ORAL INFLATOR VALVE Low Pressure Air to BC Low Pressure Air Inlet Quick Disconnect Air Channel Oral Inflation Air Spool Valve FIGURE 1-28. BC BALANCED LOW-PRESSURE INFLATOR VALVE
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