No Stupid Question - O2 Rebreather Mode?

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

helios

Contributor
Messages
75
Reaction score
9
Location
Copenhagen, Denmark
# of dives
200 - 499
I've been looking through the MOD3 requirements and noticed one of the open water skills is 'oxygen rebreather mode in depths less than 6m'. How is this accomplished on a JJ, or is it even possible?
 

AJ

Contributor
Messages
831
Reaction score
555
Location
Netherlands
# of dives
500 - 999
Keeping setpoint manual to 1.0? Not that hard to do, did that with MOD 1 training already.
 

grantctobin

ScubaBoard Supporter
ScubaBoard Supporter
Messages
2,275
Reaction score
2,084
Location
Chicago
# of dives
1000 - 2499
AJ:
Keeping setpoint manual to 1.0? Not that hard to do, did that with MOD 1 training already.
Nah, that’s not it. Oxygen rebreather mode begins w assumption that loop is structurally intact but you’ve lost all monitoring. You’ve bailed out, meander through deco, and get to your 20’ stop. What options do you have if you overstayed your welcome and you don’t have sufficient bailout oxygen to finish your deco obligation?
 

AJ

Contributor
Messages
831
Reaction score
555
Location
Netherlands
# of dives
500 - 999
Nah, that’s not it. Oxygen rebreather mode begins w assumption that loop is structurally intact but you’ve lost all monitoring. You’ve bailed out, meander through deco, and get to your 20’ stop. What options do you have if you overstayed your welcome and you don’t have sufficient bailout oxygen to finish your deco obligation?
Ah, got it.
 

kensuf

ScubaBoard Sponsor
ScubaBoard Sponsor
Scuba Instructor
Messages
2,897
Reaction score
4,578
Location
Gainesville, FL
With the JJ it's pretty easy.

1. Perform an O2 flush.
2. Periodically add O2 to keep the loop from collapsing and firing the ADV. * If you have an ADV shutoff, you may decide to use that, but not all JJ's come equipped with one.
3. Once every blue moon go back to step 1 to get rid of the inert gas that got into the loop from decompression.
 
https://www.shearwater.com/products/swift/

Top Bottom