SCUBA Diving Equipment
This section lists and describes the basic set of SCUBA diving equipment used by most recreational divers.
Masks
Masks enable the diver to see clearly underwater. The mask consists of four main parts.
The lens must be scratch and fog resistant and tempered glass is preferred as plastic tends to scratch and fog easily. Spitting onto the lens or rubbing toothpaste in reduces the fog build up.
The body is usually made from a soft rubber compound and it is vital for it to form a waterproof seal against the divers face. It encloses eyes and nose and allows the wearer to pinch their nose in order to pressurize his/her ears while submerged.
Drain Valves are also sometimes fitted but not as standard to aid with mask clearing.
The strap is either single or split rubber which holds the mask securely against the wearers face.
There are many different types and styles of mask available and it best to take advice from an experienced diver or instructor. The mask should seal against your face yet be comfortable. A correctly fitting mask should stay on your face just by the suction created by inhaling through your nose, without the need for a strap. Avoid full-face masks and those with an attached snorkel.
Fins
Fins are designed to propel the diver through the water with the minimum of exertion. It is made up of two main parts; the shoe and the blade. The blade should be of graduated stiffness in order to most efficiently transfer the power generated in the legs. The shoe needs to be made up of soft rubber compound to ensure maximum comfort from chafing.
Snorkel
A snorkel allows the user to breathe while lying under the surface of the water. In its simplest form the snorkel consists of two parts; a soft rubber mouthpiece which is gripped by the teeth and forms a seal under the lips and a semi rigid tube which points upwards allowing the user to draw in air without the risk of inhaling water. The most common shape is a J or L typically 40-50cm long. Too long and clearing it of water will be difficult and too short and water will splash in. Some snorkels have valves to assist clearing.
Weight Belt
The state of neutral buoyancy is achieved through attaching lead weights of a suitable mass to a belt. These help to counteract the increase inbuouncy that comes from wearing a wet/dry suit. An integral part of any weight belt is the quick release buckle, ensuring in an emergency a quick positive buouncy can be attained rapidly. Look out for one that is easy to release even with cold gloved hands and comes away easily without any snagging.
Aqualung
The components that make up the aqualung are the air cylinders, the regulator and the harness. The diver's air supply is contained in one or more high-pressure cylinders on a backpack. These cylinders are kept at 200bar, which is 100 x the pressure of a car tyre. Aluminium or steel is used for construction.As the air in the cylinder is at such a high pressure this needs to be reduced before the diver can safely breathe. A regulator is attached to the cylinder valve by means of a single A-clamp. It is a truly remarkable piece of engineering design. Taking the high-pressure mix and reducing it to exactly the same pressure as the ambient pressure of the surrounding water, it supplies air on demand and shuts off the air when the diver breathes out. There are two types of regulator; single hose which has pretty much superceded the dual hose type. The harness allows the aqualung or lungs to be carried comfortably on the divers back.