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