Why CCR?

[Kevin Carlisle]

In the wake of three deaths in one week I have a question for you guys who pilot them and those interested in them.

1 Why assume this risk when you are not a pro?
2. What advantages do they have?

I know several excellent CCR divers, and the ones I have asked all say the same thing. If you get complacent on CCR like you can on OC you will probably die. I know a lot of people think so much more bottom time with less gear. This is false, you better have the OC gear and gas to get you back to the surface if something goes wrong. I dont see that as an advantage nor do you save money on expensive tri-mix cause you still need enough to save yourself.

I know there are several places to dive where if your not sidemount then you are not going, this I see as a disadvantage. The only true advantage I see is taking pics or video where your exhaust could scare away your subject. Is that really worth the risk if you are not making money as a pro? I would love to see some good answers here and look forward to them.

 

[walke121]

The only advantage I can see in a CCR is that you use much less gas and that you don't have as much of a per dive cost when diving trimix (just a huge cost up front) but you have nulled those in your post. I couldn't see myself ever going CCR but I have much respect for those that do it safely. I'm just afraid I would end up a statistic.

 

[Scott L]

I asked DAN today after dealing with renewal about fatality statistics related to rebreather diving. They indicated that for the first time in 2008 such incidences were included within their annual accident report. I printed the 140 page document but left at office. Has anyone interpreted the data for information such as comparable deaths per number of dives vs. OC for similar diving?

 

[Kevin Carlisle]

The only advantage I can see in a CCR is that you use much less gas and that you don't have as much of a per dive cost when diving trimix (just a huge cost up front) but you have nulled those in your post. I couldn't see myself ever going CCR but I have much respect for those that do it safely. I'm just afraid I would end up a statistic.

Well actually you do have the cost if you dive it correct. You have to have enough OC gear and gas to get you from depth to surface in the event of a failure.. In some caves that could be a lot of gas.. Thats why I am asking this,

 

[Michael_Lambert]

We have been diving mixed team ( MCCR and OC ) for a couple of years now.

Pros.

- Cost, Yes you have to carry all that expensive gas as Bailout, however we all hope you dont need it.. So even if you bail out few times a season yours still ahead of the game. Depending on the units, Our mixed team the RB divers spend $15 for the dive regardless if its a 30 foot dive or 300 foot dive.

- Logistics, Its much eaiser for a RB diver to carry his bailout and a couple of small al tanks compared to a OC diver carrying there deco gas and a couple of sets of doubles.

- Redundancy ( options ), You have your loop, you have your BOV and your bail out bottles. One can switch from CCR to OC with out the need to remove the reg from there mouth, WIth some units you can switch through your deco gas agian with out removing the working reg from your mouth.

- Best Mix, You are always on the best mix regardless of your depth.

-NO wasted gas, Unlike with OC when you get blown off your dive you are not forced to either dive a very expensive mix on a dive that does not require it or your forced to dump your gas to get a mix that is appropriate.

Cons..

- Yes the unit can kill you, So can OC... a RB Diver requires to be that much more aware and pay that much more attention.

- Initial cost of the unit and training required.


I think people are getting worked up over the deaths, Yes there have been a few however the volume of deaths are going to go up as the volume of divers who use them. OC Divers die, so will RB divers.

 

[walke121]

Well actually you do have the cost if you dive it correct. You have to have enough OC gear and gas to get you from depth to surface in the event of a failure.. In some caves that could be a lot of gas.. Thats why I am asking this,

I can't remember the thread I saw earlier but someone was explaining how your bailout gas goes further with a CCR than when OC which didn't really make since to me at the time but maybe someone will chime in that has the right training and can fully explain what I read.

 

[Michael_Lambert]

Well actually you do have the cost if you dive it correct. You have to have enough OC gear and gas to get you from depth to surface in the event of a failure.. In some caves that could be a lot of gas.. Thats why I am asking this,

Yes you do have the Inital cost, however many RB divers have a standard mix regardless of there depth... Most dive the same dives over and over again and very simular profiles so they make there bail out however as in our team, their bailout could last them several hundred dives, before needing to go to it. UNlike spending that same cost several hundred times

 

[M_Bipartitus]

deleted

 

[HowardE]

In the wake of three deaths in one week I have a question for you guys who pilot them and those interested in them.

1 Why assume this risk when you are not a pro?
2. What advantages do they have?

I know several excellent CCR divers, and the ones I have asked all say the same thing. If you get complacent on CCR like you can on OC you will probably die. I know a lot of people think so much more bottom time with less gear. This is false, you better have the OC gear and gas to get you back to the surface if something goes wrong. I dont see that as an advantage nor do you save money on expensive tri-mix cause you still need enough to save yourself.

I know there are several places to dive where if your not sidemount then you are not going, this I see as a disadvantage. The only true advantage I see is taking pics or video where your exhaust could scare away your subject. Is that really worth the risk if you are not making money as a pro? I would love to see some good answers here and look forward to them.

1. The risk is not necessarily the rebreather itself, but rather the diver who is using the rebreather.

Many rebreather divers are already deep, extended range, extended bottom time, trimix divers. The problem that arises is that many newly certified rebreather divers move too rapidly along on their quest for deeper and longer dives. I know my instructor recommended (and some agencies require) 50 hours of recreational use on their units before they take normoxic trimix. But in reality... some people just start diving trimix right away. People exceed their limits. It's not the rebreather; it's the divers.

A rebreather is a tool like any dive equipment. For me and my buddies; sometimes it's the right tool for the job. Sometimes, it's open circuit.

Diving itself is risky.

2. Rebreathers have many advantages including as you stated; less gas used, longer dive times, less decompression, no bubbles.

On a 60' 1 hour reef dive, there may not be advantages, but certainly practicing using your tools are good ideas.

Let's think about a week long dive excursion without the capability of filling tanks. With a rebreather, you can take a milk crate with enough tanks for a week. Bring 1 keg of sofnolime, and you're good to go.

With all of the accidents that have occurred lately, I've yet to see one where the rebreather is truly at fault.

 

[Kevin Carlisle]

We have been diving mixed team ( MCCR and OC ) for a couple of years now.

Pros.

- Cost, Yes you have to carry all that expensive gas as Bailout, however we all hope you dont need it.. So even if you bail out few times a season yours still ahead of the game. Depending on the units, Our mixed team the RB divers spend $15 for the dive regardless if its a 30 foot dive or 300 foot dive.

- Logistics, Its much eaiser for a RB diver to carry his bailout and a couple of small al tanks compared to a OC diver carrying there deco gas and a couple of sets of doubles.

- Redundancy ( options ), You have your loop, you have your BOV and your bail out bottles. One can switch from CCR to OC with out the need to remove the reg from there mouth, WIth some units you can switch through your deco gas agian with out removing the working reg from your mouth.

- Best Mix, You are always on the best mix regardless of your depth.

-NO wasted gas, Unlike with OC when you get blown off your dive you are not forced to either dive a very expensive mix on a dive that does not require it or your forced to dump your gas to get a mix that is appropriate.

Cons..

- Yes the unit can kill you, So can OC... a RB Diver requires to be that much more aware and pay that much more attention.

- Initial cost of the unit and training required.


I think people are getting worked up over the deaths, Yes there have been a few however the volume of deaths are going to go up as the volume of divers who use them. OC Divers die, so will RB divers.

Thanks Michael.. I am not blaming the unit so to speak. I know most of it is the divers fault. But I often wonder if being a CCR diver gives some of them a big ego that leads to poor decisions.