The diving mode is largely defined by the type of breathing apparatus used.
This is the diving equipment worn by or carried by the diver for personal protection or comfort, or to facilitate the diving aspect of the activity, and may include a selection from:
The underwater environment usually requires a diver to wear thermal, sting and abrasion protection.
This equipment includes buoyancy control equipment and mobility equipment:
Buoyancy control is achieved by ballasting with diving weights and compensating for buoyancy changes during the dive using a buoyancy compensator:
Mobility equipment allows the diver to move through the water and maneuver on the spot:
These are the equipment used for monitoring the course of the dive and following the dive plan when undesirable events are avoided. They include planning and monitoring the dive profile, gas usage and decompression, navigation, and modifying the plan to suit actual circumstances.
Underwater vision is significantly affected by several factors. Objects are less visible because of lower levels of natural illumination and are blurred by scattering of light between the object and the viewer, also resulting in lower contrast. These effects vary with wavelength of the light, and color and turbidity of the water. The human eye is unable to focus when in direct contact with water, and an air space must be provided. Voice communication requires special equipment, and much recreational diver communication is visual and based on hand signals.
Diving safety equipment in the broader sense would include all equipment that could make a dive safer, by reducing a hazard, reducing the probability of an adverse event, or mitigating its effects. This would include basic equipment such as primary breathing apparatus, exposure protection, buoyancy management equipment and mobility equipment. The more specific meaning is equipment primarily and explicitly used to improve safety of a dive or diving operation. Equipment intended to improve safety in the second sense includes:
Backup or redundant equipment is equipment carried in case of failure of the primary equipment. This may be safety critical equipment necessary to allow safe termination of the dive or equipment carried to improve the probability of successfully completing the task of the diving operation if the primary equipment fails. The most common example of the former is bailout gas, carried routinely by solo, technical, and professional scuba divers, and most surface-supplied divers. Solo and technical divers may also carry a backup mask, dive computer, decompression gas and other equipment based on risk assessment for the planned dive. Some backup equipment may be spread amongst a diving team, when instant availability is not critical, this practice is termed team redundancy.
Tools and equipment too large or too heavy to be carried by a diver are generally lowered to the worksite from the surface platform. They are mostly used in professional diving applications.
Life support equipment must be maintained and tested before use to ensure that it remains in serviceable condition and is fit for use at the time. Pre-dive inspection and testing of equipment at some level is standard procedure for all modes and applications of diving. The use of checklists is known to improve reliability of inspection and testing, and may be required by the applicable code of practice or operations manual, or manufacturer's operating instructions. Inadequate pre-dive checks of breathing apparatus can have fatal consequences for some equipment, such as rebreathers, or may require the diving operation to be aborted without achieving its objective.
Diving equipment may be exposed to contamination in use and when this happens it must be decontaminated This is a particular issue for hazmat diving, but incidental contamination can occur in other environments. Personal diving equipment shared by more than one user requires disinfection before use. Shared use is common for expensive commercial diving equipment, and for rental recreational equipment, and some items such as demand valves, masks, helmets and snorkels which are worn over the face or held in the mouth are possible vectors for infection by a variety of pathogens. Diving suits are also likely to be contaminated, but less likely to transmit infection directly.
When disinfecting diving equipment it is necessary to consider the effectiveness of the disinfectant on the expected pathogens, and the possible adverse effects on the equipment. Some highly effective methods for disinfection can damage the equipment, or cause accelerated degradation of components due to incompatibility with materials.
The diving equipment market sectors are commercial diving, military diving, recreational and technical scuba, freediving, and snorkelling. with scientific diving using a mix of recreational, technical, and commercial equipment.
The commercial diving market is relatively small, but occupational safety issues keep cost of operations high and there is work that must be done in support of various industries, particularly the oil and gas industry, that make money available for high reliability equipment in small quantities. The military market is similarly constrained by small quantities, and there is a lot of overlap with commercial equipment where the applications are similar, but the technical requirements for stealth operations drive development of different equipment.
Recreational scuba and snorkelling are the largest markets, in which there is the most competition between manufacturers for market share, and in which the buyers are least knowledgeable about the technology and most susceptible to persuasion by advertising.
Technical diving is a niche market, where the buyers are willing to take higher risks than commercial operators, and there is enough money available to support a small number of manufacturers developing new technology. Scientific diving is also a small market, and tends to overlap the other sectors, using what is available, and occasionally driving development of new technology for special applications.
With the partial exception of breath-hold diving, the development of underwater diving capacity, scope, and popularity, has been closely linked to available technology, and the physiological constraints of the underwater environment which the technology allows divers to partially overcome.
The Diving Equipment and Marketing Association (DEMA, formerly the Diving Equipment Manufacturers Association), is an international organization for the promotion and growth of the recreational scuba diving and snorkeling industry. It is a non-profit, global organization with more than 1,300 members, which promotes scuba diving through consumer awareness programs and media campaigns such as the national Be a Diver campaign; diver retention initiatives such as DiveCaching; and an annual trade-only event for businesses in the scuba diving, action watersports and adventure/dive-travel industries, DEMA Show. Board Members serve three-year terms.
National and international standards have been published for the manufacture and testing of diving equipment.
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