| What constitutes the minimum equipment that | | | | reduces this air to the same pressure as the |
| recreational divers should have and use on every | | | | surrounding water. The most common form of |
| dive? To some degree, this will be a factor of the | | | | alternate air source is an additional regulator second |
| environment and the purpose of the dive. Divers in cold | | | | stage, similar to the one the diver normally breathes |
| water require more thermal protection than divers in | | | | from. This extra second stage is for sharing with other |
| warm water. Divers engaged in activities, such as | | | | divers who may run low, or out, of air. |
| underwater photography or night, deep, wreck, ice or | | | | Buoyancy-control Devices |
| cavern diving, require additional specialized diving | | | | A diver's buoyancy-control device (or BCD) is used for |
| equipment that sight-seeing divers in shallow, open | | | | two purposes. When inflated on the surface, it allows |
| water may not need. | | | | the diver to rest or swim comfortably without having |
| There is, however, certain equipment items that most | | | | to struggle to keep his head above water. Under |
| experts believe recreational divers should have and | | | | water, the BCD may be partially inflated to offset any |
| use on every dive. The following is a brief overview of | | | | decrease in buoyancy caused by compression of the |
| each of these items. | | | | diver's exposure suit during descent. |
| Mask, Snorkel and Fins | | | | Gauges |
| These are the most basic of all diving equipment. | | | | The minimal instrumentation with which every diver |
| Masks allow divers to see underwater without | | | | should be equipped with includes:a means of monitoring |
| distortion. Snorkels enable them to breathe at the | | | | air supplyan accurate means of determining deptha |
| surface without having to lift their heads from the | | | | means of measuring the time spent under water |
| water or use air from their tanks. Fins allow divers to | | | | I would also recommend that each diver have and use |
| move through the water with far great efficiency. | | | | an underwater compass. This not only makes it easier |
| Exposure Protection | | | | for the diver to navigate, it also helps eliminate the |
| Divers require protection from both heat loss and | | | | need for long, tiring surface swims at the end of a |
| abrasion. Heat loss is of particular importance, because | | | | dive. |
| water conducts heat away from the body 20 to 25 | | | | Knife or Tool |
| times faster than air of the same temperature. Divers | | | | Although the risk of becoming entangled under water |
| may become dangerously chilled in water that would | | | | is slight, it is recommended that all divers equip |
| seem uncomfortably warm, if it were air. | | | | themselves with some form of cutting tool. Depending |
| Thermal and abrasion protection may range from | | | | on its design, this tool may also be used for prying and |
| lightweight wet suits for warm-water diving to thick, | | | | measuring. |
| highly insulative dry suits for cold water diving. Most | | | | Log Book |
| divers also use some form of hand and foot | | | | Because certification cards only establish that, at one |
| protection. Wet suit boots are the most common form | | | | point in time, a diver met the minimum requirements for |
| of foot protection. Hand protection may range from | | | | certification at that level, divers record their dives in log |
| thick wet-suit mitts or light weight gloves. | | | | books. Log books provide a tangible record of the |
| Weight Systems | | | | depth and breadth of a diver's experience. An |
| Depending on a diver's natural buoyancy and the | | | | increasing number of dive resorts and charter |
| buoyancy of his equipment, he may need to use some | | | | operations require that divers present both certification |
| form of weight system to offset excess buoyancy. | | | | card and a log book before they will provide diving |
| The most common type of weighting is a weight belt, | | | | service. |
| although general options are available. | | | | Slate |
| Scuba Systems | | | | The ability to communicate under water using hand |
| Modern scuba systems integrate several components, | | | | signals is limited. So, to convey more-complex |
| including primary and alternate air sources, | | | | messages to one another, divers use specially |
| buoyancy-control devices (BCD's) and instrumentation. | | | | designed underwater slates. |
| Air Sources | | | | Using slates may eliminate the need to surface in |
| A diver's primary air source consists of a cylinder of | | | | order to talk and can add the convenience and |
| compressed air and a two-stage regulator that | | | | enjoyment of the dive. |