Well I have been diving a rebreather for about 4 years now, and I'm still alive. (yay!) So I thought I would pass along my thoughts about rebreathers for any members who may be interested.
Before buying a rebreather:
Before buying a rebreather:
- Open water and nitrox certified
- About 200 dives
- Average dive depth: 100'
- Deepest Dive: 145'
- B.S. in Physics
- Mechanically inclined and a bit of a "mad scientist"
- Rebreathers: (3) Inspiration Evolutions setup for technical (deep) diving
- Rebreather instructor, rebreather dive master, rescue diver, trimix gas blender, etc.
- Hypoxic (low O2) Trimix certified
- 400+ rebreather hours/dives
- Average dive depth: 150'+
- Deepest dive: 370'
- Percentage of dives that I do on a rebreather: 99%
- And still alive...
- I can dive 3-4 hours, over one or more dives, independent of depth one set of tanks an CO2 scrubber.
- They are virtually silent in the water. Since sea life will often approach you, it makes for a completely different dive experience.
- Fewer tanks are required for deep diving.
- Systems can be setup with multiple backup options should one component fail. In many ways I feel safer diving a rebreather then diving a regular scuba setup.
- "Bottom time" is extended on average about 20% over nitrox due to the constant high PPO2 maintained by the rebreather.
- Rebreather upfront cost, training and maintenance are much more expensive than conventional scuba.
- Since there are many parts to be serviced on a regular basis, they are not for the mechanically-challenged, or for folks who like to rinse and go.
- Pre-dive setup and checks can take several hours. I generally do most of this the night before.
- Post dive cleaning and break down takes about 15 minutes.
- The gear is heavy to move when the tanks are mounted. The weight is similar to a scuba setup with the tank attached.
- There are limited sources for parts, so availability and prices can be frustrating.
- I carry along many more tools and spare parts on the dive boat when diving a rebreather.
- I usually sling a 40 cf "bailout" scuba setup when diving. This adds to the complexity, weight, snag points, and cost of the setup.
- Buoyancy control is very different since you cannot use your lung capacity to fine tune your buoyancy. This is typically a problem for experienced divers, but one that you can overcome quickly.
- Skip-breathing has no benefit on a rebreather, so I had to retrain myself how to breathe. It is amazing to me how much I was skip-breathing unconsciously. No more post-dive headaches!
- When I started diving a rebreather, most of my friends at local dive shops and on charter boats thought I would die soon. Many asked about buying life insurance on me. I am sure they said the same when Nitrox was first used locally.
- Since high-pressure O2 (3500-4500 psi) is very difficult to find at dive shops, I prefer to fill my own tanks. Helium is also less expensive when I buy it direct from the gas supplier. I can also mix gases exactly the way I want them, and when I want them. I can also get much closer to the target (trimix) gas mix then a dive shop gas guy can.
- Not all rebreathers are the same. Mine have all the bells and whistles. Some are rebreathers are bare bones units and have few backup systems, or they are poorly designed. Buyer beware!
- If you dive a lot, a rebreather may be worth the extra cost and effort.
- If you are considering technical (deep diving) training, then a rebreather setup will cost slightly more and will provided additional benefits over open circuit gear.
- For the casual diver and divers on a budget, hold off for a while. The cost of rebreathers is coming down and they are being made safer and easier to maintain.
- I expect dive shops in our area to offer them to rent at some point, as dive shops are doing now in other locations.