Hogarthian Divers - DIR diving - Doing It Right - Diver

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The following discussion is only relevant to diving with a twin-set.
Having two first stages means that you have a back up should one of the 1^st stages fail. If one regulator fails you can simply “shut down” that side by turning off the pillar valve of the relevant side and switch to breathing off the other regulator. By having your dry-suit inflator coming off one side and your wing inflator off the other you also achieve redundancy (i.e. back-up) of buoyancy control.

Many people start off with a 15L or 12L cylinder and then, as they venture deeper/longer, they realise the need for either more gas or a back-up gas supply. Most therefore opt for a “pony”. A “pony” is a small (usually 3L) cylinder that one fits a second regulator and contents gauge to. I have nothing against “ponies” per se but I do have some comments on how they are set-up and where they are put.

Divers belonging to a Florida based organisation called the Wakulla Karst  Plains Project 
(WKPP) hold most of the world's cave diving depth/distance records, including one 
awesome three kilometers penetration at an average depth of 87 meters.
Now you might think that the life support equipment needed to survive these record breaking 
exposures would be like something from NASA - big, complex and expensive. Wrong.

The backplate is metal, generally made from stainless steel, some divers use aluminium. If you don't need the extra weight then you can use aluminum. The harness is made from one continuous piece of webbing with no clips or joints in the shoulder sections.No quick releases - quick releases are week points and will fail.

The light below is designed as a back-up light and is made from a single, milled piece of a very tough plastic called Delrin. Note that there is no switch as this is a common failure point. The light is switched on by turning the bezel.
The backup light is neatly clipped to the shoulder D-ring and lies in line with the webbing.

For open water dives is using two of them. For cave diving and wreck penetration I would use two of them as the consequences of a light failure are much more serious and one more backup in the dry suit pocket.

If you asked most people why they use a particular computer the answer will often be along the lines of “I use the xyz computer, I like it and I haven’t had any problems with it”. Fair enough you might say, but the decision of which computer to use/buy isn’t quite the same as other kit.

Although dive manufacturers release more new fin designs every year than just about any other piece of equipment, no fin is better suited for wreck, cave or technical diving than the Scubapro Jet Fin.
Based on a design that is at least 30 years old, the Jet Fin is a perfect example of a low-tech solution to better gear design. Jet Fins are manufactured out of negatively buoyant black rubber. You can therefore get rid of (or save money by not buying) ankle weights.

CYLINDER NETS/MESH

These are those plastic mesh things you slide over your precious cylinder in the hope that they will be safe from the ravages of the sea.
Most dive shops are all too keen to sell you these, often with the advice that “they will protect your brand new cylinder from being scratched and chipped” thus extending the life of the cylinder, better still “they grip the tank better”.

Most dive shops are all too keen to sell you these, often with the advice that “they will protect your brand new cylinder from being scratched and chipped” thus extending the life of the cylinder, better still “they grip the tank better”.

The standard High Pressure (HP) hose that you would get if you walked into most dive shops is 36 inches long. With a console attached to the end this increases to 42 inches. Even when using a single cylinder this is far too long as the console (even when the HP hose is run through a plastic hose guide, Velcro retainer or pocket) hangs below the diver when in the horizontal position. With a twin-set the problem is worse as the 1^st stage of the regulator is now to one side.

After your brain and body, your regulator is the most important part of your equipment. It should be regarded as a piece of life-support equipment and as such you should choose and maintain one with care. For many people new to diving, the choice of regulator is influenced by any number of factors such as:

· Shop recommendations

· Instructor recommendations

· Club recommendations

· That’s what I used when I learned to dive.