
The Water That The Coast Guard Won’t Save You From - curtis
http://blogs.discovermagazine.com/but-not-simpler/2014/05/16/water-coast-guard-wont-save/#.U3ed4i_c0wU
======
JshWright
> "It seemingly goes against all a rescuer’s training"

Perhaps, but only if you don't have any training as a rescuer... Rescuer
safety is always the first priority. A rescuer becoming another victim is just
about the worst case scenario in any operation. It dramatically increases the
resources needed, and does nothing to benefit the original victim.

My safety (and my crew's safety) first, _then_ the victim. We don't do them
any good if we're dead or injured.

That's not to say you don't take calculated risks to effect rescues... That's
the nature of the game. It's all about risk vs. reward. Entering electrified
water to recover someone who is very likely already dead is an extremely high
risk for a very low reward.

Source: Firefighter/Paramedic

~~~
dfc

      > Source: Firefighter/Paramedic
    

Ugh, HN can we please resist adopting "the reddit meme of providing a snippet
of biographical information which (supposedly) establishes your authority to
speak on the subject."[^1]

For a long time the unofficial motto of the CG was "You have to go out, but
you don't have to come back."[^2] Does your local firefighting department use
USCG Green Amber Red risk management/assessment procedures?

[^1]:
[http://www.reddit.com/r/AskHistorians/comments/21qxao/brief_...](http://www.reddit.com/r/AskHistorians/comments/21qxao/brief_reminder_you_are_not_a_source/)

[^2]:
[http://www.uscg.mil/history/faqs/LSSmotto.asp](http://www.uscg.mil/history/faqs/LSSmotto.asp)

~~~
kens
Personally, I find it very helpful to know if someone has experience with what
they are saying versus repeating something they read on a blog once.
(Obviously the former could be wrong and the latter could be right.) And if
I'm posting something, I try to make it clear if it's something I know or
something I'm just guessing at.

~~~
dfc
I also find it helpful "to know if someone has experience with what they are
saying." Where we disagree is whether "Source: XYZ" is allegation or fact.

~~~
kens
dfc, I read the "AskHistorians" link you posted above and I think I understand
better where you're coming from. It seems like /r/AskHistorians requires
statements to be sourced to standards (probably higher than Wikipedia's) with
reliable primary or secondary sources. If that's what you're looking for, then
obviously "Source: I'm an XYZ" will seem worthless.

My theory of internet discussions is there are three styles: "scientific
conference", where participants try to say accurate things to reach factual
conclusions; "debate team", where participants are trying to win for their
side; and "cocktail party", where participants are having an interesting
conversation. The problem is that you're trying to apply "scientific
conference" rules to a HN "cocktail party" conversation, and it's not a good
fit. (I'm sympathetic to the "scientific conference" viewpoint, by the way.)

To answer your question above, I don't view "Source: XYZ" as a fact, but I
consider it as helpful information. (i.e. they probably aren't lying about
being XYZ, and probably know what they are talking about, so I'll take what
they say as having a good chance of being true.)

~~~
dfc
I appreciate the manner and content of your response. I agree that
conversations on HN, for the majority of the time, are cocktail party
conversations, ie. good faith collegial conversations. However I think that
the "Source: XYZ" is also inappropriate for discussions among friends.
Elsewhere in this discussion people were discussing lethality and volts/amps.
If you, a friendly well intentioned internet stranger, make some reasonable
comment that "volts blah blah, and amps blah" I am going to take you at your
word and carry on our discussion. If it sounds like bullshit I am going to
call you out on it and ask for proof just like I would to a friend at a
cocktail party. It seems that if I am going to accept your allegation that you
are an XYZ simply because you, a friendly well intentioned internet stranger,
said that you are an XYZ I should just accept your original comment.

Adding the "Source: XYZ" is troubling for me because it seems to evoke some
magical air of authority from thin air. Summoning this cloak of
superiority/authority is out of place among friends, just as out of place as
someone showing up to a cocktail party in a lab coat. Good faith comments made
among colleagues should not require sources, but if sources are required,
legitimate verifiable sources should be used.

~~~
lotharbot
> _" Good faith comments made among colleagues should not require sources"_

I think you misunderstand the purpose of the "source: XYZ" comment in this and
many other HN discussions. It's not meant to create an undeserved air of
authority. It's meant to help contextualize the information being given.

When I talk about math curriculum, I usually tell people I teach fourth grade
math in an inner-city school. That helps people understand that I'm talking
from that perspective, rather than the perspective of a parent or an
administrator. It also helps people understand how closely my experience
matches the specific situation being spoken of (same grade level? Same
demographics?) and it suggests which lines of inquiry I'd be most helpful in
addressing (ie, "what does it cost to purchase district-wide curriculum" is
beyond my expertise, but "how do your students handle such-and-such concept"
is a great question.) It doesn't prove I'm a world-class expert or that nobody
can argue with me or otherwise unfairly imbue my comment with false authority.

I think this is actually normal in cocktail party type conversations. "I heard
this thing about [topic]." "Oh, I'm actually a [job] and here's some
additional detail about [thing and topic] based on my experience."

------
dredmorbius
Linkbait title. "Chicago's Electric Dispersal Barrier and Water Safety" would
be much more informative. Or something similar.

------
negativity

      At the river bottom there are multiple 160-foot wide grids
      of electrodes issuing 2.3 volts per inch every 2.5 
      milliseconds.
    
      According to safety reports, if you swim at almost any 
      point within the range of the electric barriers that span 
      the channel, you risk either involuntary muscle
      contractions or ventricular fibrillation.
    

I wish the article provided better information about the electrical hazard. A
mere 2.3 volts (per inch) doesn't sound hazardous at all, so I'm wondering if
immersion in water (distribution over surface area), significantly changes the
effects of the electrical field, or is it induced with very high amperage, or
is the frequency (2.5 kHz) disruptive?

If the surface area of an average human body is ~2 square yards, then the
total delivered electrical shock sounds like it's in the 10,000 volt range,
which is more readily understandable.

~~~
kens
I don't know any more about this than the article, but 2.3 volts per inch
works out to 165 volts across your body if you are 6 feet tall, which I would
expect to be deadly.

~~~
FireBeyond
Voltage across your body is not likely to be deadly.

MILLIamps (~50 or so) can be enough to electrically disrupt your heart and put
you in a dysrhythmia.

------
sippeangelo
Oh electricity, such a wild beast. If we only could find a way to turn it off
again after we've let it go.

~~~
Yetanfou
Of course they could turn it off, but then the army of carp just waiting
outside the parasitic barrier would take its chance and colonise the lake.
Hence, no turn-off, at least not for both barriers at the same time.

~~~
voidlogic
They just have multiple barriers with sufficient separation for rescue
operations... this would allow them to turn up to n-1 barriers off.

~~~
Roboprog
Then it would function like an [air]lock :-(

Open the outer door, enter the middle area, wait for the inner door. (lather,
rinse, repeat for n > 2)

~~~
twic
If the electrodes were controllable at a sufficiently fine granularity, they
could be activated in a sort of creeping barrage:

[http://en.wikipedia.org/wiki/Barrage_%28artillery%29#Moving_...](http://en.wikipedia.org/wiki/Barrage_%28artillery%29#Moving_barrage)

So there would be a number of active zones at a time, each one slowly moving
downriver, pushing back any invading carp in front of them.

You could switch off the electrodes in any section of the river, and then when
you switch them back on again later, the pattern sweeps any occupying invaders
back out.

------
pgrote
This is a photo of the construction process used to build the barriers.

[https://www.flickr.com/photos/usacechicago/6482344737/](https://www.flickr.com/photos/usacechicago/6482344737/)

------
Codhisattva
Great innovation. That invasive carp is crap for ecosystems.

------
GuiA
Why not have a net of some form on the surface of the water?

~~~
mAritz
The wording of the citation makes it seem like there are vessels traveling
along this canal.

~~~
GuiA
Ha yes, upon closer reading of the article, makes sense.

