Why use a rebreather?

[lifes an ocean]

Okay, so everytime I go to a dive shop I see at least one rebreather on display, and as I cruise around this site I see a forum for it. What is the purpose of a rebreather, and when do most divers use it/or if it is a better question, what kind of dives is it used for? I like the concept but it doesn't seem to be something used for recreational diving. Thanks for the input.

 

[TravelDive]

Because it is awesome, marine life interact in an entirely new way with you and the silence is golden! Recreational diving is what it's best for, that does not mean Rebreathers are perfect for Recreational Divers!

Have a look for yourself

Imagine looking up at OC divers from 40 metres, where the fish go down to hide from the hoy peloy and experiencing the silence.

Alan

Edit: Purely in reponse the the post below, I have to mention the fact the original post was Why use a Rebreather, not why not? I hope my comments do not appear to not reflect the concerns for the discipline, it's a question of answering the post for the reasons why I rebreather dive. I have plenty to say on why not:

C02 hit
Mark Ellyatt on Rebreather Diving
Rebreathers: I want that one!
Rebreather Fever On the Inspiration

 

[Web Monkey]

Okay, so everytime I go to a dive shop I see at least one rebreather on display, and as I cruise around this site I see a forum for it. What is the purpose of a rebreather, and when do most divers use it/or if it is a better question, what kind of dives is it used for? I like the concept but it doesn't seem to be something used for recreational diving. Thanks for the input.

Rebreathers are definitely not for recreational diving.

They require specialized training and great attention to maintenance and inspection before each dive. A mistake or omitted step can easily be fatal with little or no warning.

They are unforgiving and have killed a number of very experienced divers.

Terry

 

[TSandM]

Why use a rebreather? Several reasons: One, there aren't any bubbles. Photographers like this, because they feel they don't scare off marine life as much. Some people, like my husband, just hate the sound and feel of their exhaust bubbles.

Second: By rebreathing your exhaled gas, you can get far more time off a given gas supply. Many people diving closed circuit rebreathers (the kind that don't exhaust any of the gas unless told to do so) can use very small (like 19 cf) tanks. When you are diving expensive gases, like helium, this becomes quite advantageous.

Third: Minimizing decompression. Because closed circuit rebreathers can continuously monitor and vary the oxygen percentage in what you're breathing, they can keep the inhaled nitrogen as low as is safe for any given depth. This results in shorter decompression times for technical divers.

Recreational divers DO use rebreathers, but they are expensive, require specific training for any given unit, and are extremely unforgiving of any carelessness on the part of the user.

 

[Black Jack]

I made the switch on the technical side several years ago and it makes a huge difference there but on the recreational side I would agree with the other posts that the minimal bubbles is a distinct bonus when interacting with wildlife. Last week I saw several sand tigers slowly cruise by me as they were moving away from several OC divers. It seems the wildlife really does not know what to think of you if you are silent and so they often venture close to take a look.

I also find that I can have some seriously long dives at moderate depths with no worries about running low on air. Some of my male students have made the switch because they wanted the additional time but did not want to lug larger tanks.

I would also say that while rebreathers can and are used at recreational depths they are definitely for the advanced diver. When things are going wrong on OC the signs are usually pretty obvious but on a rebreather you may get no warning that things are screwy.

While I primarily dive CCR on the tech side I do like throwing a minimalist OC rig on and jumping in for quick, easy dives.

 

[String]

No bubbles (good for photos)
Far more optimum for decompression (always right mix for depth and deco) so longer bottom times
Far less gas use - this means you can stay down for hours and instead of paying $100 a dive for open circuit trimix you may pay $10 for the same time as the gas is recycled.

Cons:- Need a lot of discipline to drive one, must be prepared to abort at any time even pre-dive and takes a long time to set up and check - its NOT something you can just chuck on your back and jump in. They really come into their own when you start diving to trimix depths where you aren't then as limited by cost or the vast quantities of gas needed.

 

[lifes an ocean]

Interesting, thanks for the responses, just keep seeing them around and became curious. Once again thanks for the information.