Surface supply diving allows the diver to use air from the water surface to assist him. It uses many of the same procedures as scuba diving. These procedures are generally the same for all divers. However, some of them are tailored to specific equipment or diving tasks. These procedures may be slightly different for divers who are new to surface supply diving or for those who have not been certified to dive without scuba gear before.
Diver's umbilical
The primary connection between the diver, the surface supply diving equipment and the umbilical of the Diver is through the umbilical. It is responsible for carrying the primary breathing gas from surface to diver's equipment. The umbilical can either be directly attached to the diver or attached via a bell panels.
The umbilical connects diving mask to the top and includes a number of devices to ensure divers are comfortable and safe. Some of these devices could include a communications cable, a pneumofathometer and a hot water suit. These components enable divers to monitor depth and provide air in emergency situations.
Diver's demand valve
The Diver’s demand Valve is designed for increasing the pressure of air used in surface supply diving. This pressure can cause a diver to breathe more slowly and deeper than he would without the demand valve. Whether the diver realizes it or not, the air pressure can vary greatly during a dive. This can increase both the work of breathing and the hydrostatic pressure. These changes don't affect oxygen delivery to the lungs. Increased pressure allows the diver to extract more carbon dioxide from their air. This improves quality of their breath.
Divers normally inhale via the demand valve. However, the regulator controls the main air supply. The regulator is normally fitted with a single tube and held by the diver’s mouthpiece. If the diver is using a dual-hose regulator the demand valve is located inside the regulator. It attaches to either the cylinder valve outlet or the manifold outlet. The demand valve is activated when the diver breathes. It will provide gas to remote mouthpiece at ambient temperature.
Saturation spread
It is necessary to have a pressure environment in order to surface supply dive. There are several ways to do this, including a saturation system or a "saturation spread." Saturation diving allows divers to dive under pressure. They are then able to return to the surface and inhale a mixture of helium, helium, or both.
Saturation diving is commonly used offshore, close to production and drilling platforms, or in the context of rescue operations. It is crucial to be precise during a dive for this type of diving. This can be done most often from a specially designed diving support vessel or another suitable vessel. However, dynamic positioning is essential and requires reliable equipment.
Diver's fitness for diving
A comprehensive fitness-to dive examination must be completed before a diver can participate in surface supply diving. An AMED (diver's medical examiner) will perform this exam. They will also assess any other health conditions that may pose a threat to their diving abilities. The examination is valid for up to 12 months and must be renewed annually. The diver will need to pass a fitness exam at renewal.
Dive certification organizations specify the standards of medical examination. Some agencies require that a physician examine the diver, while others view the examination as largely a personal responsibility. These standards are almost always the same between different agencies. These standards are often based upon those for professional divers. However they can be adjusted slightly to decrease the likelihood of diving-related medical problems.
Diver's equipment
Equipment used for surface supply diving does not differ from equipment used by deep divers. The major difference is the gas used. The gas panel controls the gas supply for surface supply diving. The tank's pressure does not adjust automatically as the water level drops. Some surface supply diving demand Helms may have an additional feature called a “dial-a–breath” system which allows the diver or divers to adjust the level of gas in their tank.
For communication with the surface, divers need more than a tank. These devices are connected by an umbilical cables to the diver's helmet or full-face face mask. The cable should be checked for function and soundness before diving.