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Body Temp Issues -- Freezing...

Discussion in 'Technical Diving Specialties' started by ADB123, Aug 12, 2019.

  1. mafi

    mafi ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 200 - 499
    Location: Copenhagen, Denmark
  2. The Chairman

    The Chairman Chairman of the Board

    # of Dives: I just don't log dives
    Location: Cave Country!
    My SF2 is definitely exothermic. I have to switch to OC every now and then just to cool off.

    However, if she's breathing 42F air, breathing anything hotter than that, will have a huge impact.
  3. rjack321

    rjack321 Captain

    # of Dives: 1,000 - 2,499
    Location: Port Orchard, WA
    Sure its an exothermic reaction. And in places like FL its hotter than body temp.
    There is no way any CCR loop is warmer than 98.6 when used in 42F water. Mid to high 50s at best.

    I had a Revo buddy who used 18/40 trimix in his suit this winter in 38F water "because he didn't want to be bothered to get to the shop to get a suit bottle filled" Despite a 50W Santi vest on high he didn't last 45mins and his hands were too cold to operate his camera.

    The suit gas is 100% the problem, arguing that a CCR would be "better" is just misleading.
  4. The Chairman

    The Chairman Chairman of the Board

    # of Dives: I just don't log dives
    Location: Cave Country!
    Have you measured it? Probably not, but it's still a hell of a lot warmer than 42F. Hey, I'll let you post next and won't respond. It's obvious you want the last word on this. Go for it.
  5. broncobowsher

    broncobowsher Solo Diver

    Get a suit bottle. Doesn't have to be Argon, air works just fine.
    He in the suit will guarantee you will be cold.
    rjack321 likes this.
  6. PfcAJ

    PfcAJ Orca

    # of Dives: 5,000 - ∞
    Location: St Petersburg, Fl
    Seems like he measured it.
    helodriver87 likes this.
  7. wetb4igetinthewater

    wetb4igetinthewater Instructor, Scuba

    # of Dives: 500 - 999
    Location: Seattle
    Come on, Pete, the water over here is d@mn cold. Rjack is dead on, and people know how much we argue. With helium's heat conductive properties, that's a recipe for disaster. Now I'm not on CC, but will be by EOY, but no way would I want any helium inside my dry suit. I have no reservations with admitting what a wimp I am when it comes to temperature. Yes, there is an exothermic reaction when CO2 is scrubbed, but that warmth is going to be more than canceled out by the extra heat loss due to helium. The warmth is just a bonus of CC. The guys I know on rebreathers who dive for 4 or 5 hours at a time have some large batteries charging their heated undergarments. Water is cold.
  8. The Chairman

    The Chairman Chairman of the Board

    # of Dives: I just don't log dives
    Location: Cave Country!
    Helium in the dry suit is a no win. It had already been suggested, so I didn't cover it.

    The best way to get warm is on multiple fronts: not just one.
  9. W W Meixner

    W W Meixner Rebreather Pilot

    # of Dives: 500 - 999
    Location: Ontario Canada

    I didn't want to weigh in on this because I can only relate to what I do...I do not like...me me me responses but here goes...

    I have a DUI CF-200 Signature...Waterproof 5mm hood/gloves...undergarment is a low loft T-Max Heat two piece/T-Max Heat soxs...blended thermal knit crew top...use 32% NITROX for suit inflation...water in the Great lakes is always cold...39/42 F not uncommon...dive with an SCR...plenty warm for 30 min/130' dives...

    I have no experience with TRI-MIX so can't weigh in...but those who do know the thermal characteristics of TRI-MIX seem to think that using TRI-MIX for DS inflation gas is where your problem lies...

    Using my suit/undergarment/gloves/hood combo as a cold water diving example...I don't believe your problem lies with your thermal protection...especially in light of the fact that you're using a heated vest...if using TRI-MIX for suit inflation is acting like filling your suit with a refrigerant...that could certainly be the root cause of your problem...


  10. Hoyden

    Hoyden Instructor, Scuba

    # of Dives: 2,500 - 4,999
    Location: Rockville, MD
    I definitely agree that step one is changing the suit inflation gas, but the thing that really stopped me from being cold on long dives was a much better hood. I got a custom made Otter Bay hood that is 12mm thick over most of my head. Haven't been cold since then (except for once when my drysuit leaked).

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