Apart from running round the office shouting Gas! Gas! Gas!, I couldn't immediately foresee how I could make sensible use of the JMC Super Mask, submitted for test by Oceanic. Its a full-face mask system that allows you to fit your own regulator.
Professional divers use full-face masks for two main reasons. They keep their breathing orifices safely secure from the effects of polluted water, and they enable them to use a communications system, usually hard-wired, to the surface-support team.
Neither situation should be relevant to leisure-diving, unless you find the tiny amount of cold water in contact with your face when using a conventional mask really disconcerting.
I remember encountering all sorts of problems using various regulators with the original Italian-made Neptune full-face mask (see separate story). With the increased airspace between the demand-lever and diaphragm, many regulators had simply gone into an annoying free-flow on the first inhalation. Few could be detuned enough to work efficiently.
But before I had time to dismiss the idea of trying the JMC Super Mask, a second, almost identical product appeared from US technical-diving supplier Abysmal Diving. This one was already fitted with its own Abyss regulator.
The JMC Super Mask is made in America by Kirby Morgan, as is the Abyss regulator. I had already tried the regulator (Diver Tests, March) and been impressed by it, so I was confident that it would work properly in the mask for which it was designed.
One of the biggest problems with some full-face masks is that, once fitted to your face, you are compelled to breathe only from the ever-dwindling supply from your tank. However, the Super Mask comes in two parts, the mask with its four retaining straps and the clip-on breathing bib. So it is feasible to breathe fresh air and clip on the air-supplying section immediately before or after diving, just as you would a conventional leisure-diving regulator.
Both the Oceanic JMC and Abyss Super Mask are supplied in translucent silicone with coloured plastic hard parts, or in serious-looking all-black. I know which one British divers will prefer the look of!
I was able to fit some corrective lenses (only blind Bantins need apply) to the upper Abysmal mask section and use it with the Oceanic JMC breathing bib. I did this simply for convenience and speed, avoiding having to swap the corrective lenses over between tests.

 

I fitted the JMC bib with an Oceanic Delta regulator, which has the all-important de-tuning knob. It is very simple to remove the existing mouthpiece of almost any regulator and fit the Kirby Morgan interface, and an elbow joint is supplied to fit between the second stage and the medium-pressure hose, to make hose-routeing more comfortable and appropriate.
So I was left with two aspects to try. How easy and comfortable was it to use either full-face mask, and which regulator would prove best
I started with the Abyss version. To begin with, I fitted the complete mask to my face, clipping it at the back and pulling the straps tight so that the pressure around my face was even. I needed to have my tank turned on while I did this so that I could breathe, and resisted the temptation to intone: But Luke, I am your father.
Once fitted, I unclipped the breathing bib and breathed normally until I was ready to dive.
In the water, I was surprised to find that the increased air volume of the mask did not cause it to lift my face through extra buoyancy. There was no tendency for the mask to mist up, either, and any water that might have made its way past the face-seal simply collected in the bottom and was ejected through the one-way drain valve each time I exhaled. My face stayed completely dry.
The flexibility of the breathing bib allows the diver to hold the regulator mouthpiece in place in the conventional way. However, that didnt seem necessary. I soon stopped bothering and enjoyed the luxury of having nothing in my mouth and breathing through my nose. It certainly does away with any jaw-fatigue you might encounter during a long dive.
On the other hand, if you have the mask strapped on tight enough to prevent you breathing through your nose, you can conceivably remove the lower section and swap to a different regulator, as you might during a gas-switch to a richer nitrox mix for accelerated decompression in the shallows. The choice is yours.

 

The Abyss regulator, with its wide breathing-resistance adjustment range, gave me a perfectly diffused supply of air. I would say that it seemed as natural a way to breathe as could be encountered by any Darth Vader.
I was even able to amuse fellow-divers by conducting large parts of the dive standing on my head, as it were. I was also able to sing and chat to myself during the dive, though few of my fellow-divers were able to understand me.
So, yes, I found it perfectly comfortable and straightforward to use and I can see that this mask has an application for diving in cold fresh water in mid-winter.
Any criticisms Yes. The low-volume mask is positioned so far forward that the effect is like looking at your dive through a pair of binoculars. It brings a new meaning to tunnel-vision and you must make a point of moving your head about so that you know whats going on around you.
With one of these masks you could easily lose sight of your buddy while holding hands with him. The alternative translucent skirt of the JMC Super Mask supplied helped with this problem but did not solve it.
Next, I compared the JMC Super Mask fitted with the Oceanic Delta regulator. The effect was not quite so perfect. With the regulator BRA knob cranked right open it had a tendency to free-flow if I looked down. With it cranked shut sufficiently to stop that happening, and looking directly forward, the effort of inhalation caused the mask to vibrate distinctly against my face.
The effect was hardly disastrous, but the Delta regulator was less perfectly matched to the mask than the Abyss.
However, the Abyss regulator is an expensive piece of kit and, no doubt, the JMC Super Mask will be popular with those who want to use a full-face mask with a regulator they already own. How that will perform cannot be anticipated until you have tried it.
I used both masks in the benign waters of the Bahamas. Totally inappropriate, I hear you say.
Well, after one dive, we came back to the boat to find it floating in a sea made red with a tide of stinging thimble jellyfish. The only way back was to swim through them.
Suddenly I found that the mask had a tropical application andI was able to surface without a single irritating sting.
What does JMC stand for I forgot to tell you - Jean-Michel Cousteau, of course!
The Oceanic JMC Super Mask costs£351 with no regulator fitted. It comes in blue or yellow and translucent or all-black. The Abyss Super Mask is available in the UK in all-black only and costs£750 with the Abyss Explorer regulator pre-fitted, or£499 only with the Explorer second stage fitted. All the individual components are available separately as replacement parts. Gas-switching blocks and fittings for use with rebreathers are also available.

  • Oceanic SW 01404 891819. Abyss UK 01403 267079


    width=300
    IT MUST BE VERY IRRITATING FOR ANY MANUFACTURER who brings a product to the marketplace, only to realise that it is less good then it could have been. And its worse when some jumped-up journalist points out the defects. So it was with the original Ocean Reef full-face mask. I tried it, I found problems, I received the lawyers letter.
    width=225
    The Ocean Reef Neptune II features two revisions originally suggested by Diver - a fresh air valve and the ability to disconnect the hose of the NIRA regulator..
    Sergio Gamberinis Genoese company is expert at making products by injection-moulding. It makes parts for Swatch watches and a full-face fire-fighters mask. At other times the factory makes Ocean Reef diving products. It didn't take much for Sergio to realise that if he simply changed the materials he was using, that fire-fighters mask made a good basis for a full-face diving mask.
    After our initial clash, Sergio had insisted that I needed proper training to be able to evaluate his product properly. Always game to increase my limited knowledge, I had set off to Italy to go diving with him, his chief test diver and the local sales agent.
    Can you imagine what the four of us looked like under water Something out of a cross between John Mills war-time classic The Silent Enemy and Mars Attacks!
    We prattled to each other with the aid of built-in comms units. Everything was great until we got back to the boat. Before we could hand up our tanks, we had to take off our masks.
    Now I believe that the mask is the last item you should relinquish before finding yourself on the safety of a deck. It went against the grain to lose it while in the water. I had also commented that once I had donned the mask in the boat before diving, I was forced to start breathing off the tank, and using my precious air supply.
    I thought that there should be a method of breathing even with the tank turned off and, secondly, that it would be better if the air hose could be disconnected from the mask so that I could easily and conveniently separate from my tank should I need to.
    Its a family business. Mr and Mrs Gamberini had seemed ambivalent about my criticisms but Sergio reluctantly took them on board. In his heart he knew I was right, but he had probably built up big stocks that he needed to sell.
    The UK agent did a lot to promote the original Ocean Reef Neptune II mask initially but seemed to run out of steam. There is now a new importer. It sent me the latest mask to try, and I was glad to see that it had added those two missing features.
    The Neptune II has a plug/valve which can be removed completely (probably to be lost on a rolling deck) or simply unscrewed half a turn. Unscrewing it allows air into the mask so that you can breathe normally, with exhaled air forced out past the skirt and through the exhaust port.
    The NIRA regulator can also be disconnected from its hose, just as you can disconnect the hose of your drysuit. So you can keep your mask in place while passing up your tank and BC before climbing onto the boat.
    The original idea was that the Ocean Reef mask could be fitted with the users own regulator, but this proved problematic because the additional air space between the demand valve and the point of demand caused most to go into irrevocable free-flow.
    The Neptune II mask now comes fitted with the NIRA demand valve. It looks much like any other, including a dive/pre-dive venturi switch and a breathing-resistance adjustment knob for altering the cracking pressure of the valve.
    It has to be connected to your own regulator first stage and you must be sure that the interstage pressure provided by this is suitable. So the first thing was to find a suitable first stage.
    It is important to tighten the mask evenly onto your face, using the six adjusting straps. There is an issue of the buoyancy provided by the larger-than-normal airspace in the mask - tighten it unevenly and it may try to lift off your chin while under water.
    To enable you to place the mask over your head easily, the bottom straps are left well undone. They have large locating toggles to make them easy to find and tighten once on your face.
    The front of the mask is acrylic and in danger of getting scratched, so a protective vizor is fitted. Presumably scratched vizors are not too expensive and are certainly easy to replace.
    The advantage of acrylic is that it does not mist up easily. On top of that, the Neptune II has an internal oral/nasal mask to direct exhaled breath to the exhaust port.
    How do you clear your ears The mask has a couple of comfortably soft bars inside. These jam either side of your nose and are adjustable to suit you. You simply push the mask firmly onto your face and clear your ears as normal.
    Any water that makes its way inside is ejected through the bottom exhaust port with exhaled air so that, fully flooded mask apart, you dont get to notice it unless you invert.
    Once in my drysuit, with hood, full-face mask and dry-gloves fitted, I felt very remote from the outside world. I looked as if I could survive anything a terrorist might want to throw at me. It took a few moments to realise that few of those with me could hear what I was saying. I felt I had to shout. Remember that early sequence in The Graduate The whole experience felt like diving within a small submarine, a human submarine!
    The mask I was sent had no communications unit. As I pointed out to the importer, it would be pointless if I had no-one to talk to.
    The Ocean Reef Neptune II full-face mask costs£352. The comms unit is extra, and it's also available without a surface air-valve, for those good at holding their breath!
  • Sea & Sea 01803 663012