Will I ever dive deep on helium?

[uwsince79]

I agree...

No Dive Bomb......no wreck.....

TAM Dive
Some other good software is the Decoplanner and the zplanner ( and this is free). If you guys don't know try this link great for software and up to date information and research on the matter.


http://www.cisatlantic.com/trimix/tools.htm

 

[Lost Yooper]

Hey Steve,

I've been out of town, but I see things have really taken off around here.

Let me see if I can address some of the points that were directed to me:

"What L_Y and others have said about deep diving makes good sense and I intend to make that trip to Florida (I already got the T-shirt!). It's just that I see that there are some problems with diving deep on mix with regards to training, logistics, and execution. Is diving to 165ft on helium safer than on air? I'm not sure."

You're right, all of those things can be a problem. It becomes a matter of risk assessment. Trimix is absolutely safer than air in every aspect -- hands down. Besides all of that, you'll actually remember what you saw at 165' which is a bonus. Personnally, I probably wouldn't dive to that depth on vacation without helium and deco gasses.

"Can't be holding up non- gas divers with our extended deco. And now that we're on gas I guess our stops will be deeper, more frequent, and overall longer than if we were on air. Sounds complicated...I better not make any mistakes. Well, that’s why I took my training from the best of the best!"

The only reason you'll be in the water longer is because the air divers won't know what the heck they're doing. If you do your deco correctly, you can get out quicker than they will on air using navy tables. You'll also be "cleaner" and mucho safer. For air divers to deco out correctly takes about the same time (perhaps longer) as a helium diver -- all other things being equal.

"I guess before I go I should lay out some cash for that Abysmal software so I can generate some specialized tables for my mix. I don't really know. Perhaps I get tables when I take my class."

Deco Planner is cheap -- like $70 or something, and it's a proven program. I have Z Planner which is too conservative.

I agree with Uwsince79 in that there are some instructors of various agencies that are up to snuff and have enough common sense to train the right way. The difference is you can count on GUE's standards, and you don't have to wonder "as much" about their instructors. Regardless, if you go GUE, you'll probably end up spending less by the time you get through trimix than if you went with any other agency. Why? Most agencies have a bunch a crazy prerequisite classes such, as deep air courses, that you have to spend big bucks on before you get to trimix.

Everything boils down to personnal risk assessment -- what's your life worth?

Mike

 

[GreenDiverDown]

 

[DeepSeaDan]

As someone who has enjoyed alot of He. in my commercial diving career, I can attest to its' benefits. The beauty of working as a diver includes utilizing high technology & they PAID ME to use it!

Know this:

> with very few exceptions, all of my heo2 diving was conducted utilizing a hot water suit for thermal protection. Being 6x lighter than air, he. really sucks the heat from you respitorily.

> the head clearing benefits are truly remarkable. I recall many surface gas dives ( utilizing heo2 without the benefit of a diving bell) where I'd descend to a pre-determined depth on air & then halt my descent to perform the gas switch. Invariably I'd have quite a buzz on at the time of switching. The supervisor would switch from air to bottom mix & I'd vent the hat till that telltale change in velocity of gas entering the helmet told me I was receiving heo2. I'd also perform a long count, & very soon my voice would change from normal to the hilarious "Donald Duck" squawk so prevalent when breathing he.. In an instant my buzz would be history as everything came into sharp focus. I could then get on with my job in much better condition.

>As I understand it, H.P.N.S. is as much a function of increased he. density as it is rapid compression. The syndrome was first encountered when the researchers at Duke University were pushing the envelope for breathable gas mixes at extreme depth. Around the 1800' mark, divers in saturation were experiencing "helium tremors" as blowdown continued. At these depths, the density of he. was making it as problematic a gas as N2 was at correspondingly shallower depths. I remember the problem was partially solved by introducing one or more additional inert gases (argon & neon I believe) in the breathing mix to "buffer" the effects of the now troublesome helium.

If you want to use this gas in a scuba bottle, be wise & get the necessary training & understand your limitations...personally & technically.

Best Fishes,

D.S.D.

 

[100days-a-year]

DeepSeaDan.thanx,probly not Argon due to being very,very narcotic.Neon, I believe is only expensive so that was probly it.Believe it or not Hyrogen/oxygen mixes have been used ,but I don't know if only experimentally.Most studies suggested that the descent rate could have an effect on HPNS but not eliminate it.But as you said ,very deep...outta the range of OC scuba unless it's one way trip......

 

[Ron Brandt]

This last summer I finally got to mixing up a few tanks of trimix and proving a point to a buddy of mine. Both of us are instructors.I am not CERTIFIED(key word) to dive this mix but with the use of free software that has been mentioned in another post I went for it.

Dive buddy on air , he claims 165 is his personal narc limit due to the "fine"IANTD DEEP AIR , ADVANCED NITROX $2000 dollar course he took . Me on my own blend of 21/36 .

It was amazing to watch him. Everything normal down to about 100ft. After that he kept trying to figure out his compass. Started looking around and just being goofy. I turned the dive at 140ft.

It took alot of shaking to get his attention to turn the dive. I have never done this dive with so much clarity. After we surfaced and were debriefing ourselves he told ME I was making very funny and wierd hand signals. He will not admit he was narked.

As a point of interest we have both done deep dives past 160 on air ,something I will not do again.

Expensive , a bit . I all ready had the 02 for nitrox blending .The HE ran me $40 CDN for the tank. Total cost , about $20 per tank.

Worth it ? You bet. I will possibly be using it when I take students on thier "deep dive" speciality.

Ron

 

[Liquid]

100-days-
are you sure you ment 500'?
isn't it a bit to much to dive without any kind of suport?

I know HPNS may take affect at about this depth.

As for diving with a mixture of hydrogen/oxigen-
I know several attempts at very deep dives on such mixtures were conducted fairly recently. The oxigen percentage was beeing kept low enough to avoid any kind of detonation. I don't have any solid data on this at the moment though.

Anyway-As far as I know, today no kind of dives are being made on a regular basis to depths of over 200 meters, and even these are not being made as much as they used to in the 70's and 80's (I am not reffering here to experimental dives, but to comercial dives). Today most dives for over 200 meters (and usualy even shalower than that) are done using special "hard" suits, that keep the diver in lower pressure than the ambient pressure.

 

[100days-a-year]

liquid,yes I meant 500',buuuuut I said with little support not no support.I'd prefer 2 boats if possible,1 to stay on the anchor and one to follow the drifting divers decoing.We have a spring here 30 miles out that is 500' to 600'.There is an informal competition to get an accurate reading on the depth.Next year someone will probly do it.So far I've been halfway .Consider tho that this was with one 21ft boat and one 17ft boat.2 guys going deep,2 support divers(only if needed as we carried all gas)and 2 guys fishing .If it wasn't for the distance we'd do these every wkend we could.

 

[DeepSeaDan]

Hello Liquid...

I believe hydrogen useage is limited by its' molecular instability ( read: propensity to detonate ) as opposed to its' volatility when combined with oxygen.

As to the relationship between depth, rate of pressurizeation & h.p.n.s., I can tell you that in the bad old days, we used to employ a technique called "bell bounce diving". The procedure was to lower the diving bell to working depth with the bell sealed @ atmospheric pressure; when all was ready, we would compress the internal bell atmosphere as fast as our ears could clear till we reached lock-out depth. At that point, the diver designated to "lockout" had to scramble into his gear & get out to work as bottom times were very limited. We would use this technique to depths in excess of 500' & I'll tell you, the diver was one shaky hombre' leaving that bell, at times you'd exit & just hold on to something immovable & pray for your world to stop spinning!

As to manned deep diving, there remains a very active global segment of "saturation divers" ( divers living at working depth pressure in chamber complexes built-in to oil rigs, dive support vessels, work barges etc. etc., & travelling to the worksite via the diving bell ). While one atmosphere armoured diving suits play an important role in deep work, their functionality is limited to the dexterity of their manipulators. Most of the labour intensive, hands-on skilled diving is still done by sat. divers. It is also possible to fabricate subsea sat. habitats to encompass specific work sites, such as a damaged pipeline or platform node in need of repair. These habitats seal around the structure & are blown dry with inert gas. Hyperbaric welders lock into the habitat after exiting a diving bell & conduct the entire repair in the dry. Those lads make big coin & if I'm not mistaken, the record depth for a subsea pipeline repair stands at 1800'! The wear & tear of bounce diving is eliminated as the divers remain under pressure for up to 28 days before being rotated out. My longest sat. was 35 days & I remember being more than ready to exit that tin can for some quality time ashore.

Remotely operated vehicles (R.O.V.'s) do alot of the inspection work divers used to do & are continually evolving into more & more useful tools. Again, their ability to work is limited by their robotic arms & manipulators.

Personally, I can't wait for liquid breathing.

I hope this puts the whole picture in a somewhat clearer perspective.

Regards,
D.S.D.

 

[Liquid]

100-days-
The kind of dive you describe really sounds interesting, though I still wouldn't say it's for everybody...

DeepSeaDan, a few things-
I take you it you are still working as a saturation diver, or at least used to, for a long time. I know this kind of work pays a lot of money, but is very danegerouse. I belive deep bounce dives are not really made today anymore, to dangerouse.

As for the deep dives- are dives below 200 meters still made regularly today?

I understand it is very problematic. There is also the issue of the bones deterioration dessise (can't remeber it's name) associated with saturation diving, that inflict a lot of comercial divers.

I used to play with the idea of becoming a comercial diver myself, for several years, to make some good money, but eventualy I decided not to.


As for liquid breathing- I have a friend that his dream is to research this issue, and be the one to make the great break-through. Personaly, I belive this issue is far to complicated to be made possible in any near future. I talked to him about it about a week ago, and explained several points that in my opinion made it almost imposible, and it made him depressed. Do you know about any site on the web that might hold some good data on this subject?