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Looking to Buy a Rebreather

Discussion in 'Rebreather Diving' started by SentinelAce, Jul 5, 2021.

  1. rddvet

    rddvet Contributor

    # of Dives: 50 - 99
    Location: Florida
    1,654
    1,616
    I would have thought that everyone is taught to turn on your oxygen before anything else. Both units I'm certified on oxygen its absolutely on before you put the unit on your back. That should be standard. Scary that it's not.
     
    cathal and kensuf like this.
  2. stuartv

    stuartv Seeking the Light ScubaBoard Supporter

    # of Dives: 500 - 999
    Location: Lexington, SC
    9,907
    5,765
    I was taught that the rEvo Pre-Jump checklist is intended to be performed after the unit is donned and you're (otherwise) ready to splash. When you finish the checklist (which includes the pre-breathe), you can stand up and giant stride yourself right into the water immediately. So, as @broncobowsher alluded to, if you follow it strictly, you'd have the unit on, open the dil and do its checks before you ever open the O2.

    Like @broncobowsher, the way I have come to actually do the pre-jump is that I turn on dil and O2 and all the electronics before I ever don the unit. When I get to those steps in the checklist, it's now checking to make sure they're on, rather than actually turning them on.

    I heard of an O2 fire once that happened when a CCR diver turned on their O2. I would not care to have that happen while wearing the unit...
     
    cathal likes this.
  3. rddvet

    rddvet Contributor

    # of Dives: 50 - 99
    Location: Florida
    1,654
    1,616
    I'm surprised. It seems like a bad idea to have the oxygen on so late in the checklist. Glad yall are adjusting that yourselves. It's asking for somebody to jump in without access to oxygen. Add a hypoxic dil and that's bad bad
     
    cathal likes this.
  4. broncobowsher

    broncobowsher Contributor

    2,110
    1,574
    If there is anything good about turning it on after it is on your back, you have the muscle memory training for the valves.
     
  5. flymolo

    flymolo Contributor

    433
    205
    “Never put a tombstone on your back” is what I was taught. I thought that was standard practice?
     
    OceanEyes, _Ralph and cathal like this.
  6. stuartv

    stuartv Seeking the Light ScubaBoard Supporter

    # of Dives: 500 - 999
    Location: Lexington, SC
    9,907
    5,765
    I can see how somebody might think the way it is is a good idea. The pre-jump checklist is short and it's organized so that you open dil and do all the dil-related checks first. Then, you open the O2 and do all the O2-related checks. When you're done, the loop is implicitly at a pO2 of 0.7 or higher and you're ready to splash. Also, if you skipped the step of turning on the O2, there are several later steps that should ensure you catch that error.

    Also, if you're NOT going to follow the checklist, then it seems like it doesn't really matter what order the steps are in. You could still splash with the O2 off...
     
  7. Wibble

    Wibble Contributor

    # of Dives: 500 - 999
    Location: UK
    1,251
    963
    Need to check the ADV, hence dil first then O2.

    It kind of makes sense to turn on the dil and suit inflate, then get into the rig. Tend to suck on the ADV from in front of the unit before I climb in. Connect suit inflate and get everything tightened up, then check drysuit inflate + deflate, wing inflate, suit heater. Computers on wrists, then turn on O2, and validate that works with solenoid after changing setpoint. Sort of left to right as you're sitting in it.
     
  8. flymolo

    flymolo Contributor

    433
    205
    I would think it's a lot harder to screw it up if you first turn on oxygen and dil and make the loop breathable before ever getting into the unit.
     
    cathal and kensuf like this.
  9. stuartv

    stuartv Seeking the Light ScubaBoard Supporter

    # of Dives: 500 - 999
    Location: Lexington, SC
    9,907
    5,765
    Why are you implying that you can't check the ADV with the O2 on?
     
  10. evandroairton

    evandroairton Instructor, Scuba

    # of Dives: I just don't log dives
    Location: Ribeirão Preto - Brazil
    145
    79
    I like AP! They are just as good as any CCR as long the operator use it well. My first was a classic, now upgraded with Golem TOS CL and AV1 head, by the way, AV1 rocks! A guy gave me a flooded evo +, and soon Will instal a vision within it.
    Just Love mine, a friend has a JJ and they are quite similar on the base design.
    Although not as popular on this side of atlantic i would keep on using them for a good time. My sidewinder sticking with travel, cave and not só deep stuff.
     

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