• Welcome to ScubaBoard


  1. 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. Login or Register now by clicking on the button

Diving air to 60m

Discussion in 'Advanced Scuba Discussions' started by John Bantin, Jul 17, 2019.

  1. almostDIR

    almostDIR Barracuda

    # of Dives: 25 - 49
    Location: Finland
    234
    118
    43
    he probably has twin steel 12L 230bar tanks which are normally filled to betweem 200 and 230bar final pressure but if he would want to overfill them to 300bar the would do the 25' bottom time.


    thankfully I have a source of cheap scuba helium if I ever need it so no need to go over 40m on plain air and if i ever need to dive to 60m when having enough experience I can just take 50% and 100% with me
     
  2. helodriver87

    helodriver87 DIR Practitioner

    # of Dives: 200 - 499
    Location: Alabama
    152
    195
    43
    Apologies if I missed it earlier in this thread, but have you ever done a dive on mix?
     
  3. Dan

    Dan Great White

    # of Dives: 500 - 999
    Location: Texas
    4,998
    2,647
    113
    Pretty exact number you quoted there. What’s so special about 30.2m relative to 29 or 31m? I can easily move my arm, where my wrist dive computer is on it, up and down and change my depth by 1m.
     
  4. mac64

    mac64 Barracuda

    # of Dives: 5,000 - ∞
    Location: Ireland
    253
    83
    28
    Decompressed on oxygen mixes, never used helium for the very simple reason I never seen a need to use it. Plus when I looked at the run times and the cost I thought no way.
     
  5. helodriver87

    helodriver87 DIR Practitioner

    # of Dives: 200 - 499
    Location: Alabama
    152
    195
    43
    So... You've never used helium. Period. No clue what the difference (or lack thereof) may feel like. But you're going to sit here and say narcosis, gas density, hypercapnia, etc are all overblown and that helium is unnecessary? You literally have zero relevant experience to compare the two.
     
    Ryan Mcshane, pauldw, RyanT and 4 others like this.
  6. mac64

    mac64 Barracuda

    # of Dives: 5,000 - ∞
    Location: Ireland
    253
    83
    28
    I have no use for it but by all means you use it if you wish.
     
  7. helodriver87

    helodriver87 DIR Practitioner

    # of Dives: 200 - 499
    Location: Alabama
    152
    195
    43
    That's my point though. You have no idea. You don't have the relevant experience to make that call. I think a trimix class would be incredibly eye opening and change your tune in a hurry. But I get the impression that you're too set in your ways to consider anything new or different.
     
    Ryan Mcshane, Jack Hammer and PfcAJ like this.
  8. helodriver87

    helodriver87 DIR Practitioner

    # of Dives: 200 - 499
    Location: Alabama
    152
    195
    43
    My grandpa refuses to use a seatbelt because "cars never had them when he was a kid and he got along fine". He's still kicking, but I don't think anyone would agree that what he does is smart. Deep air is the exact same mindset.
     
  9. mafi

    mafi ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 200 - 499
    Location: Copenhagen, Denmark
    103
    71
    28
    As the guys before me said:
    • there is no scuba police, everyone can dive to the best of their knowledge and ability
    • we are happy that you enjoy deep air and are still alive
    • the undisputed fact is that you are narced in that depth and CO2 retention and WOB are real dangers for you as well
    • you never dove Tx so you have NO FRAME OF REFERENCE for this discussion at all
    Why we came at you so strong is that you are often wording your subjective reality as THE TRUTH without any Tx experience and against most recent, credible scientific data. You just can't know what you do not know. It's Dunning-Kruger effect and we all fall for it from time to time and it's up to people around us to stop the misinformation before anybody gets hurt.

    Go back through the resources we shared with you, it might teach you a lot of things you have not even considered before.
     
    TrimixToo likes this.
  10. Germie

    Germie Cave Instructor

    # of Dives: 1,000 - 2,499
    Location: Netherlands
    501
    337
    63
    Some divers, DIR and some agencies promote helium at 30m already. That is in my eyes for 99.9 % of the dives around 30m way too shallow, too expensive and a waiste of the expensive rare helium. I have never used a 30/30 or a 32/30 which is 'the' gas to use then (30/30). I never found that even in currents and only pull and glide possible that ean32 was not the best gas for me. Cheap, better than air. I never felt myself overbreathing a regulator then.
    I havent done such circumstances on ccr ( northsea wrecks), only oc. But did caves like Ginnie and little river on air diluent. But the conditions there are easier than on the northsea. But if you want to use a trimix then, already at 30m, no problems. I dont pay your bill.
    Helium or not is a personal thing. But be a thinking diver. The 30.2 is an example as 30m is the limit.

    The depth you start using helium is personal and somewhere between 30 and 60m. But all divers I know that decide to use deep air take also decogases. I dont know any diver that says are is the best at 60m. Yes I know divers that say we dont need helium at 60m, but they still take decogases and this is a small group. More divers take helium from 55m. And most from 45m. Also only a few from 30m.
    For myself it depends on temperature, ccr or oc, currents, etc. But 99% of my 50m dives or deeper is on ccr with high helium.
    Ccr gives you more options, onboard and offboard diluents can be different and switched if you want.

    I knew one diver that dove regularly to 70,80,90m bounces on air, but he was lost last year on such a dive and still never found back.

    But as soon as people start a decompressiondiving course, they never go back to deco on backgas.

    The effects of narcoses can change from diver to diver, and from dive to dive. Yes it is interesting, and yes it is such a nice feeling in your hands if you go down as fast as possible to 45m ( it dissappears after a few menutes, but you feel completely zen then :) )
    But to state air is safer, that is not true. 50m on air is also not directly dangerous. But 60m means going over extra limits as po2, wob, etc. So do a course, entry level tx course brings you to 51m on 21/35 and max of 15 minutes accelerated deco. Then you can feel the difference between air and tx.
    And maybe change your mind. Start becoming a thinking diver.
     
    Khrissi, rsingler and Dan like this.

Share This Page