Rebreathers are not really a new device at all, apart that is from in the field of recreational diving. They were first developed in the late Victorian era and came into their own when they were used to great effect some years later during WWII. They were however very limited by the technology of the day and divers could not use them on particularly deep dives for fear of convulsions brought on by acute oxygen poisoning.

The AP Inspiration is a modern design of closed circuit rebreather - that is to say the unit takes the diving gas mix you are breathing and recirculates it round and around endlessly through a closed breathing circuit of which your lungs form an intimate part. A "scrubber stack" then removes from the loop the toxic carbon dioxide you exhale with every breath As the oxygen pressure reduces in your breathing gas due to the fact that you are using up a little of the oxygen with every breath, then a computer in the Inspiration measures the level and periodically injects little squirts of oxygen back into the loop in order to maintain the desired oxygen pressure. It's not quite that simple though because the pressure is actually maintained at a far higher level than the 21% oxygen in ordinary air and the upshot of this is that the rebreather does not load a diver's body up with dangerous nitrogen to the same degree that one would experience diving with a SCUBA set. The risk of the dreaded and potentially fatal "bends" is therefore greatly reduced and the diver can stay down safely for longer periods. In addition the constant re-circulation of the breathing gas mix means that the quantity of gas one must carry is far less than that required were you to be using a SCUBA set - every  time you breathe out on SCUBA the gas is lost into the water and so a much bigger cylinder is required. Typically we would have to carry perhaps as many as six 12 litre cylinders to get the same length of dive time as we can get from our single 3 litre oxygen cylinder on the Inspiration. A further benefit of this rebreather is the fact that it makes no bubbles, apart from during your ascent, and so as a result fish will swim literally right up to your face at times allowing you to easily get up close and personal with the wildlife! Of course this makes it a perfect delight for photography.

There are perhaps two down sides to the Inspiration rebreather the major one being it's weight. With an additional bail out SCUBA cylinder and the lead weights required to get you under the water - well sometimes it's all you can do to waddle down to the boat quite frankly! But in Malta we dived in wetsuits with lightweight travel frames so it was much, much easier than diving with them at home.

The second more serious issue is the fact that it takes a lot of training to become sufficiently skilful to dive on the unit and you must constantly practise those skills to stay on top of your dive. The Inspiration rebreather is an awesome piece of equipment when it is being used in properly trained hands and working correctly but I think it is true to say that it is a very unforgiving device if not treated with absolute respect. It is far too easy to be lazy and cut corners during the preparation to dive phase, and failing to keep a close watch on the  computer handset readings could result in your dive becoming a one way trip. That said, proper training and sticking religiously to the rules means you can enjoy safe diving with all the advantages inherent in the device.

So scroll down the page now and take a look at the photographs we shot during our intensive "Perspiration week" in Malta...

The M.V. Rozi off Marfa Point...

Click on any of the thumbnail pictures below to show a bigger image...