The A.P.Valves Buddy Inspiration.

The Inspiration is a fully closed circuit rebreather manufactured by A.P.Valves in England. It uses a twin over the shoulder breathing bag design and comes with two 3ltr cylinders, one for diluent and one for oxygen. It has a computerized Oxygen Controller system consisting of two micro-processor control units with digital displays and separate power supplies, three oxygen cell sensors and a solenoid oxygen injection valve. The electronic controller is a voting logic system which automatically instructs the solenoid to inject oxygen into the mix to replenish the oxygen the diver has metabolized and maintain the ppO2 at the chosen Setpoint. The Inspiration has two default Setpoints for the partial pressure of oxygen in the breathing mix - 0.7 bar and 1.3 bar. As with many electronically controlled units the setpoint of .7 is used at the surface to avoid having the solenoid continually fire in an effort to keep a setpoint of 1 or higher. The Inspiration uses a setpoint of 1.3 for main part of the dive.

It also has a specially designed harness, available in small, medium and large, and 16kg wings style Buoyancy Control Device with an Auto Air - emergency demand valve/jacket breathing valve/inflator. There are manual diluent and oxygen feeds to the left and right counterlungs which come in two sizes, medium or large, depending on your lung volume. The cost of the unit is £3009 incl. VAT with the Auto Air and £2962 incl. VAT with the AP200 Standard Inflator.

Having dived an Inspiration it appears to be a well manufactured unit. Diving the Inspiration It has certainly undergone testing for WOB and sensor accuracy. One fault I would find with it is that the size of the tanks which can be fitted is limited by the moulding of the housing. There is only room for the 3 ltr cylinders and any extra bailout gas needs to be carried externally by the diver.

Like all closed circuit rebreathers, care needs to be taken in checking the O2 levels and referencing them against the known variables of drive gas and depth. While my own personal preference is against having an automatic addition because of the tendency to become complacent and reliant on it, the Inspiration uses a number of audible alarms and other automatic cross checks to attempt to keep errors to a minimum. My own preference again would be to run a lower setpoint, around 1, as running 1. 3 like the Inspiration does leaves less room for error at the top end of the scale. A.P. Valves appear to be quite confident in the ability of their electronics to keep the loop PO2 stable.

At present the only Inspirations in Australia are owned by Barry Hallett of Southern Cross Divers in Sydney. Barry can be contacted at Southern Cross Divers on +61 (02) 99695072Fax +61 (02) 99698801 Click here to contact Barry

Barry is selling the units in Australia and providing rebreather training and technical training in general. The units are also available for rental so contact Barry for more information.

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