Halcyon: RB80 Rebreather System Configuration

Halcyon presents the next generation of rebreather technology: the RB80. Extreme diving activities merely show that the Halcyon is demonstrably one of diving's most capable and useful rebreathers:

While the first generations of the Haclyon Rebreather clearly demonstrated its unique and reliable design, earlier versions were large and relatively more difficult to manage in certain diving situations. By working with rebreather expters such as Reinhard Buchally, Halcyon's design and diving teams to reduce unit size while maintaining inherent design benefits associated with Halcyon's unique operating system. The resulting RB80 is easily the most unique and capable rebreather ever devised.

Design features such as the patented resistive alarm feature were mated with new features like an automatic water collection and removal system. With its stunning new design, the RB80 is eminently prepared to safely support the average diver while still enabling the aggressive exploration diving in pratically any concievable environment.

Show your DIR Diver colors at your local divesite with new Halcyon shirts and hats. We're now offering a Halcyon DIR Dive System shirt and baseball cap with Halcyon's new logo.

Halcyon shirts and hats are available through your local Halcyon dealer.


RB80 Configuration Notes

RB80 configured for ocean diving

The Halcyon rebreather is configured in much the same way as a set of doubles for open circuit double tank diving. Divers must carry ample bailout to complete the dive on open circuit should the rebreather fail. Therefore, a Halcyon diver would wear back mounted doubles with an isolation manifold. The Halcyon RB80 mounts unobtrusively between a diver's double cylinders on a modified backplate. Shallow open water diving could allow a small single tank to be mounted to the side of the RB80 in the same manner that one would mount an drysuit inflation or bail-out bottle on a single cylider.

The appropriate tank size varies with dive activity and environment. In most open water settings aluminum 40ft3 bottles (or smaller) would allow ample gas supply while longer-range diving or cave penetrations would commonly call for 80ft3 or larger cylinders.

Supply gas manifolds
The Halcyon rebreather is offered with a dual inlet gas manifold that allows divers the ability to plug various gasses into the system, and change them during the dive as conditions and/or depth vary. Divers may use any mix that would be appropriate for open circuit diving, gaining the benefit of the rebreather by greatly extending the mileage a diver would get out of the supply.

RB80 divers leaving a cavern zone

Pre Dive Planning & Preparations

Gas Duration
The Halcyon is a powerful gas management tool. This system increases gas efficiency an average of eight times more than conventional open circuit consumption. The Halcyon also provides notably greater longevity than popular semi-closed rebreathers, which provide for equivalent efficiency or allow for the use of various bottle sizes.

Gas Choice
The Halcyon operating system minimizes the extreme nature of oxygen variation common with other semi-closed rebreather systems. While using the RB80, the deeper one dives the less of a gap exists between supply oxygen fraction and breathable gas supply. However, this oxygen drop can be dangerous if the diver is not respectful of the potential oxygen variation. Oxygen percentages can vary from around a 20% drop (drop from supply gas) near the surface to about 3% at depth. The extent of the oxygen drop varies according to supply gas and the depth of the dive. These factors may be calculated and are among the critical aspects to Halcyon rebreather training. One benefit of the Halycon system is that this oxygen drop reaches a plateau at a given depth and is unaffected by workload.

Understanding Rebreather Designs {next}

A manifold combines the supply of two cylinders, allowing the diver to breathe from both cylinders at the same time. All of the newer manifolds permit divers to place two redundant regulators on their twin tanks and to shut off either one while maintaining access to both cylinders. The manifold ensures that a regulator failure does not limit the diver’s use of any breathing gas. The valve controlling the failed regulator is simply shut down, allowing the diver to access all the cylinders’ contents via the second regulator.

DIR Tips courtesy of Global Underwater Explorers