Scuba Diving Equipment

Scuba diving relies on a range of specialised scuba diving equipment to make it possible for you to breathe safely underwater and move around in the maximum of comfort. Much of the training involved in scuba accreditation relates to the understanding and use of this scuba equipment so let’s take a look at what is involved.

Scuba Set

A scuba set is what gives scuba its name. This is the apparatus that will allow you to breathe underneath the water. In most scuba sets, exhaled air is simply breathed out into the water. These are known as open-circuit scuba sets. Closed circuit scuba sets, where exhaled oxygen is recycled to be breathed in again are also known as rebreathers. Rebreathers give a longer dive time per tank of gas but are more common in technical diving. All scuba sets are composed of several different parts working together to supply a diver with oxygen.

Diving Cylinder

Diving Cylinder

Diving Cylinder

This is a high pressure gas cannister usually made from steel or aluminium that is worn on the divers back and contains the oxygen mix to keep him alive. Most recreational divers use a mix the same as air, 21% Oxygen and 79% Nitrogen although different gas mixes such as Tri-mix can be used for deeper, more advanced diving.

Diving Regulator

A regulator is designed to control the pressure at which gas is released from the diving cylinder. The gas must be released at ambient pressure (this changes as a diver ascends or descends in depth) and is delivered to the diver through a demand valve into his mouthpiece. The mouthpiece is connected to the tank via a single hose and an additional connection is used both to inflate the buoyancy aid and supply a secondary, back-up breathing piece for use in emergencies.

Stabiliser Jacket

A stabiliser jacket, also known as a stab jacket, buoyancy compensator, buoyancy control device or diving vest, controls the depth at which a diver can remain immobile. They often include a back plate upon which the diving cylinder is mounted and which serves to protect the divers spine. The jacket is inflated with gas from the dive tank and can be regulated to allow the diver to descend and ascend as he wishes by filling or emptying gas. Neutral buoyancy is achieved when the diver is neither ascending nor descending but floating in place without the aid of external stabilisation. This necessary dive skill can be learned with practice.

Snorkel

Snorkel

Snorkel

So as not to waste precious tank air when swimming or resting on the surface of the water, divers breath through a snorkel. Thus they can continue with their face inside the water, observing their planned route of descent without impinging on their future dive time.

Counter weights

Depending on the mass of the diver, the type of wetsuit used and a few other factors, weights usually need to be added to the buoyancy control device. This is to counteract the natural buoyancy of a diver which will float him to the surface.

Wetsuits

A diver loses heat 25% more rapidly when submerged in water. Wetsuits are designed to trap a layer of water next to the skin which heats it up. There are many types of wetsuits, long arms or vest type, short legs or long. Wetsuits come in many different thicknesses suitable for different water temperatures.

Wetsuits also protect a divers skin from abrasion on rocks, corals and harmful contact with marine life. In tropical water where it is too warm to wear a wetsuit, a spandex diving skin may be used instead. Shallow diving in such places carries the added risk of sunburn as the sun’s rays are magnified by the water and a diving skin protects against this too.

Dry Suit

In very cold water conditions, a wet suit does not provide sufficient insulation. In these cases a more expensive dry suit can be used. Dry suits are sealed and do not let in any water at all. they must be made from resistant fabrics so as not to tear, and normal clothes can even be worn under them.

Flippers

Flippers

Flippers

Swimming flippers or swim fins are attached to the feet to help divers swim quickly for long periods without getting too tired. Flippers also protect the feet from sharp objects on the sea bed special care must be taken with flippers so as not to damage fragile corals.

Diving shoes

Where it is not practical to wear flippers, a diver may opt for neoprene diving shoes. They may also be necessary to insulate the feet in cold water. Neoprene socks can be used in combination with certain types of flippers to provide extra insulation.

Diving Masks

Goggles

Goggles

A diving mask forms an airtight space between the water and the divers eyes. This allows a diver to see, dependent on water visibility conditions. A diving mask needs to be chosen to fit comfortably to a divers face and not let in water. For divers with less than perfect sight, prescription diving masks inserts can be made.

Diving Knife

Diving Knife

Diving Knife

This is a tool and not a weapon. Diving knives are made from either stainless steel or lighter rust proof (but more expensive) titanium. Some knives come with a serrated edge for cutting ropes and a blunt end for prying things open. A diving knife can be a life saving piece of equipment if you should become ensnared in some underwater obstacle such as a fishing net or marine plant.

Diving Watch

Diving Watch

Diving Watch

For use underwater, a watch needs to be water resistant to a reasonable depth and have illumination. Divers set the dials on their dive watches to measure how much time they have until their air expires. These days, dive watches come with many advanced features such as depth gauges, thermometers and memory functions, virtually replacing the dive computer.

Dive Computer

Before dive computers, divers always had to make table based calculations to plan their rate of ascent at the end of their dive. Dive computers are able to process information in real time, during the dive. They can plan an ascent rate based on the ever changing variables of the actual dive and therefore bring a great level of spontaneity to recreational diving. If a diver ascends too rapidly he risks serious injury or even death due to the bends. Dive computers, however, cannot be relied on completely, as measurable factors such as the divers physiology can impact upon safe ascent rate.

Underwater Cameras

Underwater Camera

Underway Camera

Specialised diving cameras are resistant to pressure and water, they will also need a good flash. Underwater photography is a skill in itself but with all the amazing sea life you wont be stuck for photo opportunities. Alternatively, many normal cameras and video cameras have underwater housings designed specifically for them.

Dive Lights

An underwater flashlight is essential for activities such as night diving or cave diving where there is a lack of light. Dive lights can also be used for communication between divers. Diving video lights and camera lights are used to illuminate the subject matter in underwater photography.

Underwater Compass

It is essential that you know where you are underwater but, in a strange undersea world bereft of reference points, this can sometimes be tricky. Underwater navigation is a skill all scuba divers must master and an underwater compass is invaluable to this. Usually filled with oil to aid the movement of the needle and resist water pressure, underwater compasses are often wrist mounted for ease of use.

DPV

A diver propulsion vehicle is an underwater vehicle which allows divers to reach more remote areas. There are many different styles of DPV, a common one is where divers hang onto handles at the back and are pulled through the water. There are dangers associated with DPVs and changing depth too quickly, therefore they are usually used by more experienced divers.

Tips on buying diving equipment

  • Some shops offer no-fuss returns if the equipment doesn’t work out for you. A good example of this is a dive mask, where a badly fitted one can cause lot of discomfort and even be dangerous.
  • Think about the longevity of your diving gear. It is going to suffer a lot of wear and tear. If you want it to last then it is best to fork out for higher quality in the first instance.
  • It will be easier to find spares and replacements for big name diving brands.
  • Shop around on the internet and in dive magazines, prices vary.
  • Read equipment reviews in scuba diving magazines and take advice from more experienced divers, not the retailer who has a product to shift.
  • In choosing colours go for brightly coloured diving gear. Visibility is more important than fashion sense.
  • There are loads of second hand dive gear around. Many divers try scuba out and decide it isn’t for them after buying all the gear. Make sure that you don’t do the same! This hardly used second-hand diving gear can be a great bargain. Check free advert papers such as Loot.