Surface supply diving involves using air from the surface to assist the diver. It uses many of the same procedures as scuba diving. Many of these procedures can be used for all divers. Some are more specific to 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 Diver's umbilical is the primary connection between the diver and the surface supply diving system. It is responsible for carrying the primary breathing gas from surface to diver's equipment. It can be attached directly to the diver's apparatus or through a bell panel.
The umbilical connects the diving mask to the surface and contains many devices that help divers remain safe and comfortable in water. This could include a communication cable or a pneumofathometer. This allows divers to keep track of their depths, and also provides additional air for emergency situations.
Diver's demand lever
The Diver's demand valve is designed to increase the pressure of the air used during surface supply diving. The demand valve can make a diver breathe slower and deeper than normal. The pressure of the air can fluctuate during diving, regardless of whether the diver is aware. This can increase the work required to breathe, and also the cracking pressure and hydrostatic pressure. These changes will not reduce oxygen delivery to lungs. Increased pressure allows the diver to extract more carbon dioxide from their air. This improves quality of their breath.
Divers breathe normally from the demand valve, while the main air supply to the regulator is controlled. The regulator usually has a single hose, and is attached to the diver’s mouthpiece. The demand valve, which attaches either to the manifold outlet or cylinder valve, is found in the regulator's body if the diver uses a dual hose regulator. When the diver breathes, the demand valve will supply gas to the remote mouthpiece at ambient pressure.
Saturation spread
A pressurized environment is required for surface supply diving. There are several ways to do this, including a saturation system or a "saturation spread." Saturation dive is when divers are put under pressure by a saturation accommodation and then returned to the surface using a helium-based gas mixture.
Most commonly, saturation diving is used offshore, near production platforms and drilling platforms, as well as in the contexts of salvage 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. A reliable system is required for dynamic positioning.
Diver's fitness-to dive exam
Divers must pass a complete fitness-to-dive exam before participating in surface supply diving. A diver's medical examiner will conduct this examination. He or she will evaluate any health conditions that could pose a danger to their ability to dive. The certification is valid for a maximum of 12 months. It must be renewed every year. The diver will have to pass a fitness check at renewal.
The medical examination standards are specified by dive certification agencies. Some agencies require a medical practitioner to perform the exam, while others leave it up to the individual to do the exam. 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.
Divers equipment
The equipment used for surface supply diving is not very different from that used by deep divers. The primary difference is the breathing gas used. In surface supply diving the gas used is set at the gas panel. As a result, the pressure of the air in the tank does not automatically adjust as the depth decreases. Some surface supply diving demand helmets might have an additional feature called a "dial a breath" system. This allows the diver the ability to adjust the tank's gas level.
Aside from the tank, divers also need a set of voice communication devices for communication with the surface. These devices are connected by an umbilical cables to the diver's helmet or full-face face mask. Before a dive, the diver should check the cable for sound quality and function.