Oxygen usage (was: incident at Perris)

[LouDiamond 1]

Chuck has actualy rigged up a bail out bottle system with mask for wingsuit jumps that he said would work. I think it would REALLY be a good idea to have O2 on a BM high alti jump since it's common to get flights of 90-100 secs from 12,500 with a deployment alti of 5,000. Which means one would be at or above the mentioned altitudes for a longer period of time. I think the normal bailout bottle with mask and gentex helmet is completly do able either rigged inside the suit if it permits or to the outside of the suit much like a belly mount . The suit works really well to make it worth the effort IMO and I'd do it in a heart beat if I had a bailout bottle. In fact, I just might start looking for a bailout bottle since I have all the rest already

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[Billy 0]

This is the jist of what I was referring to in my reply in the original post.
If were using the system in place properly, at our "high" alt jumps of 23K MSL, it should be just fine for most folks. But if you are older, outta shape, a smoker, been drinking the day/night before, dehydrated, ya better be heads up and have those close by be keeping tabs on you also.
At those altitudes you will desaturate quickly after you take off your 0's and start moving around.

PS- Climbers at altitude will take weeks/months to allow the physiology to adapt to the low partial pressures at altitude, the 02 level is the same, it's the pressures that drop. It's why 8000m is know as the death zone...

PSSS- Your blood won't boil with rapid decompression at altitude,, it "bubbles" as the Nitrogen & C02 turns to gas ; )

Natural Born FlyerZ.com

[mjosparky 4]

Lou,
I have used the PHAOS only once and like the side feed. It keeps moisture from pooling in the exhalation/inhalation valve. The six man consoles I was talking about were made by Conex, now out of the O2 business with MBU-12 masks with quick fittings and single pin comm. plugs. We do a lot of work with the navy and their test jumper unit has gone to the PHAOS system. They are not interchangeable so we will have to upgrade so. Big bucks.
Thanks for the last post, it should make it clear to all that above 18000 you can wake up dead.
Sparky

My idea of a fair fight is clubbing baby seals

[riggerrob 643]

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Aviation O2 has a lower moisture content. Important so water doesn't collect and freeze in the system. This is also why you end up with dry mouth, nose and throat from it.

Medical O2 has a higher moisture content. My guess is so that it's more tolerable for long term usage as it helps avoid the dry mouth, nose and throat.

Industrial (welder's) O2 can have a higher level of impurities that may be harmful to humans.

More info HERE.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

According to a recent issue of Aviation Consumer Magazine, all three grades of oxygen come from the same plant, the only difference is price.

www.aviationconsumer.com

[quade 4]

I'm simply pointing out the definitions according to the FAA Flight Surgeon's Office.

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According to a recent issue of Aviation Consumer Magazine, all three grades of oxygen come from the same plant, the only difference is price.

While that may be true for some gas plants, I have a pretty good idea that it does NOT hold true for all of them.

quade -
The World's Most Boring Skydiver

[freakydiver 0]

"Further, I've always been amazed by the guys that climb mountains without O2. It's one thing to be off it for a few seconds in the door waiting for exit and another thing entirely climbing up the side of a mountain at 18,000 msl."

But most of us work up tolerances to be able to climb mtns wo O2. I still feel it after going up and down in a plane out in Colorado all the time but never have any problems hiking to 14k (higher in Alaska).

-- (N.DG) "If all else fails – at least try and look under control." --

[billvon 2,998]

>Further, I've always been amazed by the guys that climb mountains
>without O2.

It's not without its drawbacks. An old girlfriend of mine climbs for real (as in K2, Everest, Gasherbrum etc) and doesn't use O2. When she gets back from a climb to 26,000+ feet she's lost about 40 IQ points; it takes a while for her brain to recover, and she's got very little long term memory now.

[Billy 0]

What they say,, "when there's nuthing left to burn,, there's always gray matter..."

Natural Born FlyerZ.com

[SkymonkeyONE 4]

I brought a set of twin 53's, my mask and Gentex with me to Quincy 2001 for Jari to use on his planned "most time in freefall jump." We rigged the bottles by means of a custom harness, sideways and under the BOC. No, it didn't prevent pulls. The HP hose went into the same hole as your left legstrap and then over across the chest. It came out on the other side in such a manner that the hose did not bind at all. We jammed the bottles over at Mullins' tent and were set to go. I was to be the phys tech on board for him and then land with the plane on the first attempt. It didn't go when we could not get the requisite FAA approval, plus the fact that we partied excessively the night before. Chris Needels took a lot of pictures of our rigging and practice sessions. Jari still has copies.

Chuck Blue
MFFJM (among other things)

[mcrocker 0]

Quote

Further, I've always been amazed by the guys that climb mountains without O2. It's one thing to be off it for a few seconds in the door waiting for exit and another thing entirely climbing up the side of a mountain at 18,000 msl.

Climbers normally spend weeks if not months at high altitude base camps aclimating to the O2 and pressure levels.

There are two issues really.

1) O2 levels in your body as you gain altitude you take in less O2 and your O2 level drops. Breathing pure O2 or O2 enriched air helps with that. Low O2 can lead to black outs, grey outs and hypoxia.

2) depressurization. Under pressure gases (O2, Nitrogen, etc) are more readily absorbed into a liquid. As you release the pressure the gas is forced out of the solution. (think soda bottle) If you do it slow enough your blood supply can absorb it and return it to your lungs. Do it too quick and you create bubbles which can collect in your joints (bends) or in your blood supply (cardio embolism). Getting bent HURTS A LOT. It can cause permanant nerve damage and even kill. A bubble in your blood is almost certainly lethal. You can reduce the risk of getting bent by prebreathing pure O2 at ground level (increasing O2 and decreasing Nitrogen) or you can decrease your pressure slowly.

If you went from sealevel to the top of everest in one day you will more than likely die even if you were breathing O2 on the summit.

Take a look at some SCUBA charts. If you spent 1 hour in 30 feet (2 BAR) of water breathing compressed air. You cannot just shoot to the surface without getting bent. You need to surface slowly (1 foot/second) and a safety stop at 15' for 3 minutes is highly recommended. I don't have my diving charts handy so the numbers/timing might be a bit off.

The difference in pressure from 30 feet below to sealevel is one atmosphere. What is the difference in pressure between sealevel and 25,000 MSL ?

A plane in a large formation going up high for a big way may climbe slow enough for the nitrogen in your system to release without a problem. Symptoms of the bends can go unnoticed for days

[quade 4]

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If you spent 1 hour in 30 feet (2 BAR) of water breathing compressed air. You cannot just shoot to the surface without getting bent.

Damn! Really?

I'll admit my information is -way freekin' old - because I took SCUBA in high-school and haven't done much since, but . . . I was always taught that anything shallower than 1 atmosphere of pressure underwater (33ft) was good for unlimited time without decompression. You can't hold your BREATH at 33ft and surface, your lungs will explode, but as far as the bends . . . no issue.

Can anybody point me to some more modern references than these 25-year-old synapses I have floating around in my head.

Edited to add . . . http://www.nwn.noaa.gov/sites/ndc/pdfs/USNDeco1.pdf Wow! They changed the unlimited no-D depth to 20 feet in 1999. The 30 ft no-D time limit is now only 405 minutes (6 hours and 45 minutes).

The reason I picked 18,000 ft in my mountain climbing example is because at 18,000 feet you have about 1/2 the pressure as at sea level.

quade -
The World's Most Boring Skydiver

[mcrocker 0]

Quote

Edited to add . . . http://www.nwn.noaa.gov/sites/ndc/pdfs/USNDeco1.pdf Wow! They changed the unlimited no-D depth to 20 feet in 1999. The 30 ft no-D time limit is now only 405 minutes (6 hours and 45 minutes).

Hrm, My 3 yr old dive table says max no decompress time at 35 feet is 139 minutes when breathing compressed air. I don't have a nitrox chart handy but it would be longer. So, my original post was about 1 hour off.

139 minutes at 35 feet puts you into pressure group V. It will take you 2 hours and 48 minutes at sealevel to release all of the built up nitrogen in your blood and put you back into pressure group A. A safety stop at 15 feet is still HIGHLY recommended.

The point is, if you remove pressure too fast you will boil your blood. I don't think climbing to 25k in a plane climbing 1k feet/minute is 'too fast' but it is something to be concerned over. prebreathing O2 will reduce the nitrogen that is in solution in your blood and reduce your risk of getting bent. Symptoms of the bends can be very subtle and not noticed initially. Continued exposure can compound the problems.

There is a lot of medical information on tissue absorbition rates relating to SCUBA and nitrogen absorbtion. Some of that information is relevant to high altitude low pressure exposure.