
A man who ran out of air at the bottom of the ocean - acdanger
http://www.bbc.com/future/story/20190423-the-man-who-ran-out-of-air-at-the-bottom-of-the-ocean
======
diveanon
What is really interesting is that at depths below 65m the real danger isn't
running out of air, but that air itself becomes toxic due to the higher
partial pressure of oxygen and it's effect on the nervous system.

Tech and commercial divers breathe exotic air mixtures which are hypoxic and
include helium to mitigate this.

Dive science is pretty fascinating and is still a developing field.

~~~
agumonkey
pressurized oxygen has different effects on your breathing/vascular system ?

~~~
jdietrich
At sufficiently high partial pressure, it's toxic.

[https://en.wikipedia.org/wiki/Oxygen_toxicity](https://en.wikipedia.org/wiki/Oxygen_toxicity)

Nitrogen becomes narcotic at high pressure; breathing normal air at 30m is
like being tipsy, but below 90m it can be fatal.

[https://en.wikipedia.org/wiki/Nitrogen_narcosis](https://en.wikipedia.org/wiki/Nitrogen_narcosis)

~~~
dig1
Nitrogen narcosis is usually called "drunkenness of depth" (if I translate
this correctly), because it produce effect like you are drunk.

I've seen and heard many stories of experienced divers that would do silly
things due this effect; that is why you always have to have partner with you
and the rest of the crew near by.

This effect is highly dependent of person and I've seen guys goes beyond 40m
without getting this at all.

~~~
folkrav
I'm no professional diver, but did a bunch of dives between 60-100ft, and it
seems like it can start happening to me around 70-80ft. Experienced divers
will be more conscious about when it happens to them, and will plan their
actions accordingly.

It's pretty eerie. It's _literally_ like being drunk, but you happen to be
strapped to an oxygen tank with 100ft of water over your head, and could get
extremely sick if you did something too stupid.

It's actually a pretty safe activity, given you follow safety rules. It's
however pretty easy to stray from them.

~~~
eitally
Yep, especially for inexperienced divers. This is why one of the cert
qualification dives is a "deep" dive, usually in the 90-110ft (30ish meters),
and why that dive is usually just a really simple descent + a few elementary
tasks at the bottom while maintaining neutral buoyancy.

~~~
nradov
Experience provides no protection against narcosis. There is no adaptive
effect. Experienced divers who think they can somehow handle it are just
fooling themselves.

------
ayakura
>If you lower the brain temperature down to 30C (86F), it can increase the
survival time from 10 to 20 minutes. If you cool the brain to 20C (68F), you
can get an hour.

Wow, I actually didn't know this until now. Is this method used anywhere in
medical procedures to resuscitate or prolong life?

~~~
sytelus
So this may be the basis of cryogenics? If you just cool down in specific way,
you can turn off metabolism and then turn back on again at later date?

~~~
nradov
Well not really. Cooling the patient down will give you a few hours at most
under ideal conditions. Metabolism isn't turned off, just slowed down. If you
freeze the patient the ice crystals damage the cells so much that revival
becomes impossible.

~~~
the_pwner224
Flash freezing (using liquid nitrogen to freeze something really quickly) is
used successfully for smaller objects, such as frozen berries and frozen
vegetables that you can buy at the grocery store. The Wikipedia page on flash
freezing links to this [0] site with some more discussion. The Wiki page also
says that flash freezing still can take a few hours, so there are still ice
crystals created, but a lot less/smaller than if you just put it in the
freezer.

Overall it seems it's just a matter of waiting for technology to advance to
the point where we can very move a 150 pound 2-meter-tall 1-foot-deep object
from 98 degrees to 30 degrees, and at that point the science fiction will
become reality.

[0]:
[https://web.archive.org/web/20120111233417/http://www.biotec...](https://web.archive.org/web/20120111233417/http://www.biotech.ufl.edu/EM/data/freeze.html)

~~~
ChrisRR
Even speaking as a brit, your mixture of metric and imperial and metric
fascinates me.

I personally would've written 150lb, 6'6 tall, 1ft deep, 37 to 0 degrees

~~~
OJFord
150lb? That always strikes me as distinctly American, as opposed to 10st 10lb.

~~~
saalweachter
I'm so glad America got away before y'all went stone-crazy.

Redefining the hundredweight, seriously?

~~~
OJFord
Hey, for a '1,000 pennyer' I'll advocate for your pound-as-largest-unit
madness.

~~~
saalweachter
You had options! The London stone for wool was 12.5 lbs, which would give you
the same 8 stone to the hundredweight without redefining a _hundred_ weight as
112 lbs.

Or if you wanted to go the other way -- there were plenty of other definitions
of the stone in use at the time, after all -- you could have gone with 16
pounds, to maintain parity with the dram and the ounce. Y'all still likely
would have screwed up the hundredweight, as 128lb, but you might have at least
fixed things by making the ton 16 hundredweight/2048 lb, which would at least
have been some lovely binary fractions.

But _14 pounds_? That's just _madness_.

------
Thaxll
The documentary is on Netflix, it's worth a watch:
[https://www.netflix.com/watch/80215139](https://www.netflix.com/watch/80215139)

~~~
BuildTheRobots
Netflix just gives me a "Netflix Site Error – Page Not Found".

What's the documentary called, so I can find it by other means please?

~~~
iamcreasy
It's called "Last Breath".

------
latch
Reminds me of the fantastic movie The Abyss (1)...vaguely recall a similar
scene where there's N tanks of oxygen for N+1 people, so they submerge 1 of
the crew to lower her (i think) metabolic rate.

Curious why they don't have emergency unmanned drones with the crew or why
they don't have emergency tanks at their work site (which he was able to get
back to)

(1) - Not sure how well it has aged
([https://en.wikipedia.org/wiki/The_Abyss](https://en.wikipedia.org/wiki/The_Abyss))

~~~
jdietrich
_> Curious why they don't have emergency unmanned drones with the crew or why
they don't have emergency tanks at their work site (which he was able to get
back to)_

There was a UUV in the water, which helped to locate the casualty but wasn't
capable of performing a rescue.

Bailing out to open-circuit SCUBA doesn't help for very long, because of the
immense pressures involved. As you go deeper, you need more pressure to
inflate your lungs. A cylinder that lasts for an hour near the surface will
only last for a couple of minutes at 100m. Tethered divers do carry bailout
gas cylinders, but they're very much a temporary fix for brief losses of gas
supply.

There are major logistical problems with portering dozens of gas cylinders to
a job site that may actually increase the overall risk, because of the far
greater time spent in the water. That pile of cylinders won't help you a jot
if you lose the job site or you're incapacitated. Saturation divers are
increasingly switching to closed-circuit rebreather bailout systems, which
recirculate the breathing gas and so are far less affected by depth.

Even that is only a partial help because of the effects of hypothermia - if
you lose your umbilical, you lose the warm water supply that stops you from
freezing to death. You also lose your lighting and communications, which
substantially impedes your ability to self-rescue.

[https://www.jfdglobal.com/products/commercial-divers-
equipme...](https://www.jfdglobal.com/products/commercial-divers-
equipment/rebreathers/cobra-compact-bailout-rebreathing-apparatus/)

~~~
LeifCarrotson
> A cylinder that lasts for an hour near the surface will only last for a
> couple of minutes at 100m

And unfortunately for saturation divers, you can't pressurize cylinders on-
site to make up for the difference.

Pressurizing your tank to 210 bar (which puts the same stress on the cylinder
walls as 200 bar at the surface) doesn't change the factor-of-10 increase on
the other side of your P1V1=P2V2 balance.

Not to mention that you need even more air for decompression time...

------
rkagerer
What an incredible tale. Ironically, this story at the moment shows up
directly beneath one titled "Hacking the Casio F-91W to Handle 1000+ PSI"

------
cyberferret
Main article aside, I have to take the article to task for the section where
they talk about an airplane and the oxygen masks that deploy when the aircraft
depressurises and the passengers find it "hard to breathe".

Having gone through a depressurisation chamber as part of my flight training,
at 35,000 feet (the normal cruising altitude for most passenger aircraft), it
isn't actually hard to breathe. In fact, it feels quite normal. Your body just
doesn't get enough oxygen into the bloodstream because the density of O2 in
the stuff you are breathing in is so low, which causes onset of hypoxia.

The very reason why we do the sessions in the chamber - so that we can detect
the symptoms of hypoxia particular to our own bodies, because there is
normally no way to tell that you are no longer in an O2 rich atmosphere until
you notice your fingernails turning blue and flashes of lights on your retina
as well as feeling slightly tipsy (my own symptoms).

At higher altitudes (50,000 feet and up), then yes, there are issues because
your diaphragm cannot create enough pressure differential against the outside
air pressure to make you inhale and fill your lungs. My flight instructor was
a test pilot in the 50's and 60's and he said when they were at that altitude,
they were literally force fed liquid oxygen through their masks. They couldn't
breathe it in, so they just had to open their mouths every few seconds and LOX
would be shoved in (at freezing temperatures too, which used to dry out their
nose, mouth and throats according to him).

~~~
pdkl95
> so that we can detect the symptoms of hypoxia particular to our own bodies

Destin of SmarterEveryDay (with astronaut Don Pettit) recorded his experience
with that training, which included a demonstration of the effects of hypoxia
on his _decision making_ ability. He doesn't notice the rapidly increasing
symptoms:

>> [Destin fails child's shape toy test, saying the cross was a square]
"Alright you're starting to have a little shake there, you know from your lack
of oxygen. You need to start thinking about getting back on oxygen now
Destin."

>> "How would you correct for that? Can you correct for hypoxia for me?"
[Destin just sits looking confused] "Alright sir if you don't get on oxygen,
you're going to die. Go to your regulator, get all three switches on your
regulator..." [Destin looking even more confused: "I don't want to die"]

>> [they get him back on O2, fixing everything in seconds]

[https://www.youtube.com/watch?v=kUfF2MTnqAw](https://www.youtube.com/watch?v=kUfF2MTnqAw)

~~~
cyberferret
Ah, that brings back memories. That was the exact stuff we did, except that my
exercises was to count backwards from 1000 by 13's.

We were told that we could possibly make it 3 to 4 minutes at FL250 before
having to go back onto oxygen. I managed to get to 5 minutes, but was was
pretty much useless after the 3rd minute. I started to feel a real out of body
experience, and it was like I was watching my own body do stuff but I couldn't
really control it. I managed to get my own mask on and gangload the 3
switches, but I remember watching my colleagues in the chamber struggle and
they had to be assisted by the RAAF team. The guys outside the chamber kept a
hawk eye watch on all of us, and the guy in the chamber were quick to assist
those of us who were in trouble.

What amazed me was as soon as we 'gangloaded' the switches to go back on full
O2 with the masks on, recovery to full lucidity was super quick - within 1 or
2 seconds. It wasn't gradual, it was as if someone just whipped a heavy
blanket off your brain!

Side story - before we went into the chamber, we had to be fitted for our
helmets and masks, and I was seated in the 'fitting chair' in the crew room as
3 RAAF specialists slapped a bone dome and mask on me. Unbeknownst to them,
that mask had just come back from a test facility, and thus it still had the
wax seal on the end of the O2 hose to the mask.

Normally, there is no seal, so when the mask is clipped on during a test, you
can still breathe normally as the valve at the open end just opens and shuts
with your lung pressure. With the wax seal on it though, NO air gets through.

It was a few seconds of odd feeling when they snapped the mask on and I tried
to breathe in but nothing happened. I remember feeling really freaked out at
the sensation of wanting to breathe, but feeling and experiencing absolutely
_nothing_. I started to grapple with the mask release, but they thought I was
just uncomfortable with the fit and they kept slapping my hands away and
adjusting the side straps.

I went into panic mode, and I am not sure what prompted me, but I started
reeling in the trailing hose from my mask and lifted it up to see the seal on
the end. One of the crew saw it and exclaimed before grabbing the hose and
ripping the seal off. I gulped down lungfuls of air. Not the best start to my
first chamber session!

------
cstrat
Wow that was an interesting read!

This quote got me. All because of compression & decompression.

> “It is quicker to get back from the Moon than it is from the depths of the
> sea in some ways.”

~~~
petschge
The polar station in Antartica is also quite inaccessible during winter.
Winter-overs are proud of the fact that they are more remote than the ISS.
There you can get in a Soyuz and be back in 90 minutes. In Antartica it might
be a month before they can airdrop supplies, maybe four month until they can
airlift you out.

~~~
omoikane
See also:
[https://en.wikipedia.org/wiki/A_Place_Further_than_the_Unive...](https://en.wikipedia.org/wiki/A_Place_Further_than_the_Universe)

It's a great series about exploring Antartica, where the title came from the
fact that it takes longer to reach Antartica than to reach space.

~~~
jandrese
It makes sense. Antarctica is further away from almost every place on Earth
than Space is. Sea level to space is closer than Manhattan to Trenton.

~~~
thaumasiotes
> Sea level to space is closer than Manhattan to Trenton.

"Closer" is a fuzzy concept. I've seen the same point made another way, that
you can be closer to space than you are to the sea... even if you're in Japan,
a long, narrow island.

But then again, imagine if whenever you tried to drive to Trenton from
Manhattan, a tornado picked up your car and threw it back to Manhattan.

------
brian-armstrong
This article is quite fascinating, but the title is a bit misleading. The
diver was about 100m deep. He was on the sea floor but arguably not "on the
bottom of the ocean" (though maybe, by some interpretation)

~~~
hprotagonist
what is the sea floor if not the bottom of the ocean?

~~~
mc32
Well, in a way yes, but then so is wading next to the seashore. Think of the
converse “at the top of the mountain.” At least I’m thinking some peak and not
just on a slope up the mountain.

------
sytelus
Related - David Blaine's world record of holding breath for 17 minutes:

[https://worldrecordacademy.com/stunts/longest_breath-
holding...](https://worldrecordacademy.com/stunts/longest_breath-
holding_world_record_set_by_David_Blaine_80235.htm)

Which is probably already broken:

[https://www.reddit.com/r/IAmA/comments/132l2v/i_hold_the_gui...](https://www.reddit.com/r/IAmA/comments/132l2v/i_hold_the_guinness_world_record_for_the_longest/)

~~~
mladenkovacevic
I think this is the current record. 24 minutes and 3 seconds. It's hard to
comprehend.

[http://www.guinnessworldrecords.com/world-records/longest-
ti...](http://www.guinnessworldrecords.com/world-records/longest-time-breath-
held-voluntarily-\(male\))

------
Joakal
Question for the medical readers: a person dies when brain dies from lack of
blood flow, right? So all those injuries, say a car crash where heart will
stop soon. 1) Disconnect the head from body 2) plug it into a machine that
supplies blood, etc 3) the body is repaired 4) reattach head to body.
Overlooking the obvious trauma, is this possible?

While extreme/traumatic, I think it could be more reliable as other factors
below neck are taken out if equation to dramatically increase chance to
survive. Other methods rely on hoping the body isn't too broken to recover. Ie
restarting heart, etc then literally giving up as the brain dies from lack of
blood flow.

A lite version of above is cutting the veins in neck and attaching a dialysis.
Would this lite method work?

Source: Hearsay reports of moving lips from beheaded woman was literally
inspiration for this idea, not futurama heads.

Edit: [https://theconversation.com/did-anne-boleyn-really-try-to-
sp...](https://theconversation.com/did-anne-boleyn-really-try-to-speak-after-
being-beheaded-106650)

~~~
bayareanative
That's what an ECMO is... a last-ditch effort to perfuse the brain and vital
organs to see if the body can recover. It rarely does.

Head transplantation is still too "out there."

~~~
manjana
One problem with head transplantation that comes to me, is that of resources
such as hormones and neurotransmitters produced by the body (i.e. intestines
produce neurotransmitters).

Thence it is not only a problem of oxygenation of brain tissue.

------
ducttape12
> They now use emergency tanks that carry 40 minutes of air rather than five.

Glad to see the change, but why even carry a tank with 5 minutes of reserve?
Might as well just plan on holding your breath in that case.

~~~
ip26
This is just idle observation, but when you ascend the air in your lungs
expands and you are supposed to continuously exhale to prevent lung rupture.
Supposedly if you start with a full pair of lungs, you can ascend pretty much
from the bottom of the ocean on just one breath because of this.

Also somewhat related, the deeper you go the less time your tank lasts. From
what I remember, at 100m, a "5 minute tank" is probably similar in size to a
standard scuba tank.

~~~
idlewords
This is correct; scuba divers are trained to do a controlled emergency ascent
while continuously exhaling, because your lungful of air at depth will last
the whole way up, and the real risk is not running out of air, but embolism
from overexpansion.

The limiting factor in ascent (and therefore the reason for the recreational
dive limit of 60 feet) is the risk of decompression sickness. If it weren't
for that, a diver at arbitrary depth could ascend on a single breath.

~~~
Swifty
This is not entirely true, not all agencies teach a Controlled Emergency
Swimming Ascent (CESA). From memory the only one that teaches this is PADI.

Most don't as this is not a very effective or safe way of getting up once you
get bellow a few M of water.

Most agency's will teach you to do an Alternate Source assent where you come
up breathing of your buddy's air source, as this allows you to come up at a
safer and more controlled rate.

~~~
cheerlessbog
As I remember the PADI training the CESA is the absolute last resort when your
buddy is not available. I imagine all authorities would agree that it's less
bad than remaining at depth without gas.

~~~
idlewords
No novice diver is going to remain at depth in an out-of-air situation, under
any circumstances. The point of training the CESA is to teach people not to
hold their breath and hurt themselves when they panic and bolt for the
surface. This panic reflex is so strong that it takes dozens of hours of
training and practice to be able to signal a buddy and breathe off their air
supply in a real emergency situation.

You can see this reality reflected in the rescue diver certification (a fairly
advanced level of training), which revolves around how to stop people bolting
for the surface when they have trouble getting air. Rescue divers are taught
some fairly extreme measures—you pull the person's regulator, yank their fins
off, pull off their mask, and hold them down by the tank valve, anything you
can do to prevent them surfacing at high speed. Better a briefly unconscious
diver than one with an air embolism.

------
peripitea
I feel like you could make 6 minutes of air last an hour or more if you
breathed really slowly (like one breath every 30-60+ seconds). Maybe I'm
misunderstanding the device he had, or maybe it already has that assumption
built in, or maybe he just wasn't quite that efficient but that is part of why
he was blacked out but not dead when his friends pulled him up.

~~~
nradov
It's tough to relax and slow down your breathing when you're scared and about
to die. And after a few minutes of forcing yourself to breathe slowly the CO2
accumulation starts to mess with your head.

------
PatrolX
"But his survival is not unheard of either. Tipton has examined 43 separate
cases in the medical literature of people who have been submerged in water for
long periods. Four of these recovered, including a two-and-a-half-year-old
girl who survived being under water for at least 66 minutes."

Wow, 66 minutes! Amazing.

------
barrad0s
There is a documentary about this, which I recently watched.
[https://www.imdb.com/title/tt9056818/?ref_=nm_knf_t1](https://www.imdb.com/title/tt9056818/?ref_=nm_knf_t1)

------
metabrew
You're not dead until you're warm and dead, as the saying goes.

------
Mauricio_
Not reading this. I don't want spoilers for the documentary.

------
SmokeGS
Medically there are policies in various countries that differ on the term
'dead' or 'clinically dead'. Various places have different standards of dead.

This has a huge effect on organ donation rates. For my medical emergency thank
god I live in the US or my organs would have been donated already.

some places may have a policy for either 'respiratory arrest or cardiac arrest
after x period' to be considered clinically dead. If I had been in one of
those countries my organs would be in many different people's bodies.

I thank god every day that I was born in the US.

~~~
dev_dull
More info please. What happened?

~~~
SmokeGS
someone tried to kill me for exposing them raping my girlfriend and the
doctors used experimental oxygenated blood to save my life. I got really drunk
the night i was assaulted because of a related incident. During the incident
with my gf, her ex and i were trying to locate her after a party (we were in
another dorm and she called us on a cell, not hers) and she recollected she
didn't know where she was, she was naked, and that some males were holding her
close not letting her go. They would only give her clothes after a sexual act
was performed. We tried locating her but we were too late. Afterword, I and
the girlfriends ex tried pulling the call 'metadata' but it was deleted or i
was not allowed to access it.

I have a higher likelihood of suffering a stroke in my 30s due to the fake
blood injections.

My roommate was paid to keep watch while the offender tried to suffocate me.
While transported to the hospital i lost consciousness for a long time. The
hospital pretended like they had consent to inject me with the fake blood. The
hospital covered up the rohypnol in my system. The nurse there assumed i tried
to slip a gril a roofied drink and failed. The college buried the report,
blaming it all on me. My parents were shamed. My girlfriend ended up dating
the offender for 2 years due to violent threats on family. The offender got
away with sexual assault against me (buck breaking). The offender stuck his
dick up my ass so I wouldn't tell anyone of the event (i am male and it almost
worked). The only reason I survived is that I pretended to die (thanks burn
notice) only for the offender to realize he didn't want to kill anyone. I had
a brown-out of the events for about 1.5 weeks after. This will be my greatest
shame for the rest of my life not trying harder to prosecute the incident.

~~~
dev_dull
Oh my god that sounds absolutely horrific.

~~~
SmokeGS
It's worse because the offender was politically connected and there was
nothing I could do about the situation at the time i regained recollection.
The offender also had large resources to pay ex spooks to keep the situation
normal (for him), and digging up dirt on me and my family.

------
mrhappyunhappy
Great, an ad for a documentary. Fascinating story but still an ad.

~~~
ultrarunner
I got rid of my TV entirely in large part because of the ads. I run an ad
blocker. I’m not a fan of most advertising. But man, when something is
actually useful and unobtrusive I don’t complain! Imagine if every ad was a
captivating story that made you think and introduced interesting concepts
(like death being less something to fear and more about what you leave
behind). That’s not going to happen, so even if this is an ‘ad’ I for one am
quite happy with it.

~~~
mrhappyunhappy
Fair point. Sometimes I just have angry moments when I realize I’m being sold
to. I don’t stop to think that maybe perhaps it’s okay to do this if you are
sharing something interesting.

~~~
ultrarunner
I completely agree! So much of the advertising industry seems to be comprised
of people who have an enormous amount of distain for their target
demographics. People don't like being taken advantage of or manipulated, and
it's depressing that it's gotten to this point.

I just think that in this case, while they (ostensibly) want to promote a
documentary, they're presenting it in an honestly compelling way. That's about
as much as I could ask for, I think, and I wish others would reimagine how
they sell products to align more with this strategy.

