The  O2ptima rebreather training is a fully closed circuit, constant PO2, electronically-driven rebreather with built-in decompression ability. Unique in the rebreather marketplace, the O2ptima is specifically designed for the rigors ofcave diving where immediate surfacing is not possible. The resulting features are also highly desirable for wreck and deep ocean divers.

The O2ptima’s design includes minimal risk of a caustic cocktail. Two water traps in the loop along with horizontal, behind-the-head positioning of the scrubber canister create a difficult path for water to travel. The O2ptima also features a packable scrubber and Shearwater Petrel electronics. Both of these features represent major improvements in this CCR.

The O2ptima delivers excellent work-of-breathing that allows divers faced with strong flow or ripping current to breathe comfortably. Over-the-shoulder counter-lungs along with the scrubber positioned behind the head means gas has less distance to travel, so the diver does not have to work as hard to “pull” gas through the loop. This also allows the O2ptima to have smaller diameter loop hoses, which minimizes jaw fatigue.

A stainless steel frame and Rhinotec 600-denier polyester cover protects the O2ptima from tight cave or wreck squeezes and rolling boats. Hoses, regulators and tanks are kept neatly streamlined and away from potential snags inside a wreck or cave.


The IANTD Optima CCR Air Diluent Course.


Prerequisites
1. Must be an IANTD Advanced EANx or Advanced Recreational Trimix Diver or equivalent. (May be taken in conjunction.)
2. Must be a minimum of 17 years of age.


​Program Content
1. All lectures completed with IANTD Course-specific Slides pertaining to the theory in the IANTD CCR-specific Diver Student
Kit.
2. This Program must include a confined water session, followed by 6 OW dives with a minimum of 500 minutes of in-water
training time using the specific Rebreather on which they are being trained. If qualified Recreational CCR diver, the total inwater
training time is decreased to 400 minutes and the dives are decreased to a minimum of four (4) OW dives.
3. Students must complete the text with the units on which they wish to be qualified.
4. Students must pass the specific CCR test with a minimum score of 80%.
5. On a minimum of four (4) dives the student must carry a single stage cylinder or other bailout gas adequate to safely ascend.
6. Three (3) dives must be a minimum of or deeper than 50 fsw (15 msw) of which one (1) of these three (3) dives must be a
minimum of 100 fsw (30 msw).
7. To qualify from one Closed Circuit Rebreather to another Closed Circuit Rebreather, a diver must have 12 CCR dives of which
one (1) must have been within 45 days of the program on the new CCR and must complete a minimum of 200 minutes of inwater
training with at least two (2) OW dives.
8. To qualify from a Semi-Closed Circuit Rebreather to a Closed Circuit Rebreather, a diver with 20 or more SCR dives must
complete a minimum of 400 minutes of in-water training in a combination of confined water and OW environments, with at least
6 OW dives. Divers with less than 20 SCR hours must complete the entire course.