Getting Out Of The Cave

[braumeister]

Quote:

Originally Posted by Winemaker Individuals have different O2 burn rates regardless of fitness.

I did quite a bit of scuba diving until about age 50, but none after that. Night diving was actually my favorite.

I would put Winemaker's comment above as a very critical item. Especially under stress (and what would be more stressful than your first dive?), a person can go through far more air than they expect. If they use normal scuba gear to get them out, it will be critical to have a large reserve in the tank as they will be breathing at a pretty high rate.

[Jerry1]

Just read that one of the navy seals died while working to place oxygen tanks along the route. If a seal had trouble enough to die, diving out looks all the more unlikely for those trapped. Getting harder to watch.

[easysurfer]

Part of the reason why low on oxygen is because too many rescuers arrived, sucking up the air .

You'd think there be better planning.

[97guns]

From Bloomberg, Elon musk sending a team to Thailand


Musk suggested ways to help, including the possibility of inserting tubes and then inflating them with air, similar to the way bouncy castles work. The mechanism “should create an air tunnel underwater” that conforms to the shape of the cave, he wrote in a tweet. Other tweets reference the location of water and depths of different parts of the cave, making clear he had studied diagrams in detail.

[Skyward1]

Just a minor note, and the media is making the same mistake, the tanks that the divers are using are not filled with oxygen. They are filled with compressed air or nitrox or even possibly trimix/heliox which is air enriched with oxygen or helium.

Pure oxygen is actually toxic at depth and will kill you.

Hoping the best for everyone involved in this incredibly difficult situation.

[Scratchy]

I just read a blurb that an air line has been successfully installed. Tried to find details but could not. Sounds like potentially a huge step forward!!!

[folivier]

I've done hundreds of hours of scuba diving, about 1/4 of that night diving. I did a bit of cave and cavern diving. There is very little relation to open water diving and cave diving. If there is no or very little current then silting causing a whiteout and disorientation is a major concern. Especially with inexperienced divers. Water depth is also a concern due to increased air consumption, nitrogen narcosis, bends, and embolism.
Imagine this scenario: put chairs, boxes, and other objects around a large room creating a maze that is tight to maneuver through. Add a sheet over it to simulate a close ceiling and start crawling through it with your eyes closed. Then imagine breathing through a regulator the entire time.
My hopes are for a successful rescue mission.

[Rustic23]

Not a diver, but it would not appear that the bends would be a problem as the water depth they are dealing with is quite shallow.

[RunningBum]

I assume they have a line running now, so one can follow the line as they go. And I assume the kids will be tethered to an experienced diver, and a second one following to help them through the tight spots.

It's still a matter of them not panicking, or doing something else wrong, but it's not like they are putting a mask and tank on them and wishing them luck.

I'd be in favor of taking control and trying to swim out, rather than waiting and getting weaker, and perhaps being later forced to dive if oxygen runs lower and water gets higher. The kids don't have to be told how hard it is, or that someone has died already.

The whole tube thing, sounds interesting, but if it catches on a sharp rock and rips, you've got water back in it and you may be back to a swim, but unprepared.

I wonder if the narrow points can be widened, or if it's too dangerous to try, that it might cave in and block the path completely.

[MRG]

Quote:

Originally Posted by Scratchy I just read a blurb that an air line has been successfully installed. Tried to find details but could not. Sounds like potentially a huge step forward!!!

+1
A fellow on the ground there was doing an "ask me anything" on Reddit. He said there was a line and he appeared to be optimistic. He's also tweeting updates.

[samclem]

Quote:

Originally Posted by Rustic23 Not a diver, but it would not appear that the bends would be a problem as the water depth they are dealing with is quite shallow.

I haven't read anything about the hydrostatic pressure difference between the place where the kids are and the farthest point underwater. The cave might be just 2' high, but they still might have to go down, say, 50' under the water level. Either way, the kids could be pre-breathing N2-free mix long enough before the actual dive to remove any potential for the bends.

If they've got an O2 line into where the boys are, that's great news and will allow them to eventually tailor the O2 level in that cavern. It won't directly affect any problems that would be caused by any buildup of CO2 there.

With a safety line, lights, an experienced diver in front of and behind each kid as they shuttle them out, it will still be fraught with potential trouble, but the sooner they can get started, the better. It's only a matter of time before one or more of those kids develops a medical issue that will significantly complicate the problem.

I'm sure the UDT/SEAL/cave diver/cave rescue blogs and boards are covering this stuff with a degree of detail lacking in the mass media. Lots of things that appear to us to be big problems may be simple, and lots of things that appear to be simple may be really hard.

[Texas Proud]

Quote:

Originally Posted by folivier I've done hundreds of hours of scuba diving, about 1/4 of that night diving. I did a bit of cave and cavern diving. There is very little relation to open water diving and cave diving. If there is no or very little current then silting causing a whiteout and disorientation is a major concern. Especially with inexperienced divers. Water depth is also a concern due to increased air consumption, nitrogen narcosis, bends, and embolism. Imagine this scenario: put chairs, boxes, and other objects around a large room creating a maze that is tight to maneuver through. Add a sheet over it to simulate a close ceiling and start crawling through it with your eyes closed. Then imagine breathing through a regulator the entire time. My hopes are for a successful rescue mission.

The one thing that I have seen that makes sense is they were planning on using a full face mask so not a normal regulator...

[Rustic23]

I was basing my comment of the pictures we have seen and the drawing/chart posted earlier here. I realize it is not to scale, but it did not appear to have deep dives.

[Car-Guy]

Quote:

Originally Posted by Helios I think they have an airline already reaching them.

Quote:

Originally Posted by travelover I hope it is not Frontier - I hate those guys.

[Aerides]

I'm following this on AP. As of today, they do NOT have an airline:

"Rescuers have been unable to extend a hose pumping oxygen all the way to where the boys are, but have brought them some oxygen tanks."

[ncbill]

Quote:

Originally Posted by folivier The problem with drilling an access from above is where to drill? Not easy to determine exactly where they are from above.

Too deep, IIRC.

One article I read compared it to the equivalent of drilling down the length of 2 Statues of Liberty and trying to hit something the size of a subway tunnel.

[Scratchy]

AP reports that an operation to bring the boys back has begun. 13 foreign and 5 Thai divers. What amazing people to attempt such a dangerous, nerve wracking and physically grueling task. This is an awful situation but seems to have brought out the best in people. True heroes!! I hope so much to hear some good news about this soon.

[Winemaker]

Quote:

Originally Posted by ncbill Too deep, IIRC. One article I read compared it to the equivalent of drilling down the length of 2 Statues of Liberty and trying to hit something the size of a subway tunnel.

Drill/location is not a hard thing to do. The hard thing to do is get the right equipment in place, do the right surface prep for a rig setup, and commence.
Drilling holes down into coal mine entries for power, water, dewatering, compressed air, ventilation is routinely done for over 50 years.

[JoeWras]

Quote:

Originally Posted by Winemaker Drill/location is not a hard thing to do. The hard thing to do is get the right equipment in place, do the right surface prep for a rig setup, and commence. Drilling holes down into coal mine entries for power, water, dewatering, compressed air, ventilation is routinely done for over 50 years.

Right. And they don't have the time, or surface prep for it.

Has anyone ever tried to drill a hole from the outside of their house inside? It is always a challenge.

Anyway, saw on the news the same thing mentioned above. Looks like they now decided to go for it with the divers. Our church will be saying prayers this morning all involved.

[Aerides]

Initial reports (AP/Reuters/CBC, etc) are saying 2-3 boys are already out, the operation will take a few days. I hope this is true.