I'm not sure WHERE to ask this, but, how does a wet cloth
work in an airplane crash anyway?

In step 3 at 45 seconds into this video shows it in use:
http://www.youtube.com/watch?v=RXaTt...etailpage#t=49

What's the wet cloth (scientifically) doing?

On 5/15/2014 7:46 PM, Ann Marie Brest wrote:
I'm not sure WHERE to ask this, but, how does a wet cloth
work in an airplane crash anyway?

In step 3 at 45 seconds into this video shows it in use:
http://www.youtube.com/watch?v=RXaTt...etailpage#t=49

What's the wet cloth (scientifically) doing?

http://www.faa.gov/pilots/safety/pil.../Smoke_Web.pdf

Ann Marie Brest wrote:
I'm not sure WHERE to ask this, but, how does a wet cloth
work in an airplane crash anyway?

In step 3 at 45 seconds into this video shows it in use:
http://www.youtube.com/watch?v=RXaTt...etailpage#t=49

What's the wet cloth (scientifically) doing?

My guess would be that the wet cloth catches many of the smoke particles, and
the water will cool the air you inhale.

I agree with BobF; the wet cloth acts like a filter for both smoke particles and fumes that would be soluble in water.

During World War One, Canadian soldiers being attacked with chlorine gas (called "Mustard Gas" at the time because of it's yellow-green colour) were told to urinate into their handkerchiefs and to breathe through that wet cloth. The chlorine gas would dissolve in the water as it passed through the handkerchief, thereby keeping our troops safe and alive.

On Thu, 15 May 2014 20:16:19 -0400, Frank wrote:

What's the wet cloth (scientifically) doing?
http://www.faa.gov/pilots/safety/pil.../Smoke_Web.pdf

That nicely summarized FAA article explains:
- Smoke is a complex of particulate matter, invisible combustion gases & vapors suspended in the fire atmosphere.
- Inhalation of toxic gases in smoke is the primary cause of fatalities
- Carbon monoxide & hydrogen cyanide are the principal toxic combustion gases
- Carbon monoxide combines with the hemoglobin in blood and interferes with the oxygen supply to tissues
- Hydrogen cyanide inhibits oxygen utilization at the cellular level.
- Carbon dioxide is a relatively innocuous fire gas, increases respiration rate causing an increase in the uptake of other combustion gases
- Irritant gases, such as hydrogen chloride and acrolein, are generated from burning wire insulation
- Generally, carbon dioxide levels increase while oxygen concentrations decrease during fires.

And then finally, the article suggests:
- Cloth held over the nose and mouth will provide protection from smoke particulates;
- If the cloth is wet, it will also absorb most of the water-soluble gases (i.e., hydrogen cyanide & hydrogen chloride).

What's interesting is that the entire article doesn't discuss any dangers
of breathing smoke particulates, so, why it bothers to mention a dry cloth
is perplexing since we can safely assume that filtering out particulates is
merely a convenience, and not a safety issue.

So, now we're left with the a WET cloth absorbing water-soluble gases.
Of the two water-soluble gases, only hydrogen cyanide was listed in
the article as being a safety issue (the other water-soluble gas was
merely an irritant).

So, I guess we finally have the answer to "why the wet cloth?".

The WET CLOTH filters out (water soluble) hydrogen cyanide:
"Hydrogen cyanide poisoning signs & symptoms are weakness, dizziness, headache,
nausea, vomiting, coma, convulsions, & death. Death results from respiratory arrest.
Hydrogen cyanide gas acts rapidly. Symptoms & death can both occur quickly."

On Thu, 15 May 2014 18:22:53 -0700, Bob F wrote:

My guess would be that the wet cloth catches many of the smoke particles,
and the water will cool the air you inhale.

Based on the one referenced FAA article, the dry cloth does nothing for
safety, but a wet cloth reduces the water-soluble hydrogen cyanide gases.

On Fri, 16 May 2014 03:30:48 +0000, Ann Marie Brest wrote:

Based on the one referenced FAA article, the dry cloth does nothing for
safety, but a wet cloth reduces the water-soluble hydrogen cyanide gases.

Armed with the new keywords "wet cloth hydrogen cyanide", I find more
on the toxicity of HCN over he

http://www.atsdr.cdc.gov/MMG/MMG.asp?id=1141&tid=249
"Hydrogen cyanide is readily absorbed from the lungs; symptoms of poisoning
begin within seconds to minutes. The odor of hydrogen cyanide is detectable
at 2-10 ppm (OSHA PEL = 10 ppm), but does not provide adequate warning of
hazardous concentrations. Perception of the odor is a genetic trait
(20% to 40% of the general population cannot detect hydrogen cyanide);
also, rapid olfactory fatigue can occur. Hydrogen cyanide is lighter than air.
Children exposed to the same levels of hydrogen cyanide as adults may
receive larger doses because they have greater lung surface area:body
weight ratios and increased minute volumes:weight ratios."

"Hydrogen cyanide acts as a cellular asphyxiant.
By binding to mitochondrial cytochrome oxidase, it prevents the utilization
of oxygen in cellular metabolism. The CNS and myocardium are particularly
sensitive to the toxic effects of cyanide."

"In the United States, antidotes for cyanide include amyl nitrite perles
and intravenous infusions of sodium nitrite and sodium thiosulfate,
which are packaged in the cyanide antidote kit."

But, what we need to know is how effective is the wet cloth in reducing
the hydrogen cyanide gases in the cabin air.

On Fri, 16 May 2014 03:41:06 +0000, Ann Marie Brest wrote:

Armed with the new keywords "wet cloth hydrogen cyanide", I find more
on the toxicity of HCN over he

And, here's what OSHA has to say about the dangers of HCN:
http://www.cdc.gov/niosh/docs/81-123/pdfs/0333.pdf

"[Hydrogen cyanide] is capable of bringing to a halt all
cellular respiration".

"A few inhalations of high concentrations of HCN may be
followed by almost instantaneous collapse and cessation
of respiration."

"270ppm HCN is immediately fatal to humans"
"181ppm HCN is fatal after 10 minutes"
"135ppm HCN is fatal after 30 minutes"
"110ppm HCN is fatal after 60 minutes"

"Humans tolerate 45ppm to 54ppm for 1/2 to 1 hour without
immediate or delayed effects, while 18ppm to 36ppm may
result in symptoms after exposure for several hours."

So, the key question is what the HCN concentrations are in
a typical airplane cabin fire?

On Fri, 16 May 2014 03:52:45 +0000, Ann Marie Brest wrote:

Armed with the new keywords "wet cloth hydrogen cyanide", I find more
on the toxicity of HCN over he

This flight safety PDF titled "Guarding the airways", is of interest:
http://flightsafety.org/download_fil...t06_p28-30.pdf

It mentions only that the "wet cloth" prevents irritation, which we're
not concerned with in this discussion.

They also explained that the "dry" heat of a cabin fire isn't of great concern:
"the human bodys upper airway naturally provides significant protection
to the lower airway and lungs against extreme heat from hot, dry air".

I'm pretty surprised about those findings, but they in this article
specifically about guarding your airway during an airplane cabin fire.

On Fri, 16 May 2014 04:00:28 +0000, Ann Marie Brest wrote:

I'm pretty surprised about those findings, but they in this article
specifically about guarding your airway during an airplane cabin fire.

This Airbus briefing discusses HOW to use the wet towels properly:
http://airbus.com/fileadmin/media_ga..._OPS-SEQ06.pdf

"Use wet towels, a wet cloth, or a head rest cover to reduce some of
the effects of smoke inhalation. Instruct passengers to hold the wet
towel/cloth over their noses and mouth and breathe through it."
..
This onboard emergency description mentions not to use ALCOHOL:
http://www.casa.gov.au/wcmswr/_asset...r/apr_fire.pdf

"To limit the effects of toxic fumes, a wet cloth should be
placed over your nose and mouth (a headrest cover or any other
available fabric is suitable). Use water, soft drink or other
non-alcoholic beverages to moisten the fabric."

Given that alcoholic drinks are almost all water anyway, I wonder
why they bothered to mention non-alcoholic drinks?

Does alcohol on the wet fabric do anything different with HCN?

On Fri, 16 May 2014 04:00:28 +0000, Ann Marie Brest wrote:

They also explained that the "dry" heat of a cabin fire isn't of great concern:
"the human bodys upper airway naturally provides significant protection
to the lower airway and lungs against extreme heat from hot, dry air".

Here they mention the heat inside your body during a cabin fi
http://wenku.baidu.com/view/8abb4621...fcc220e6f.html

"In an aircraft accident that involves a fuel-fed fire, cabin air
temperatures could be expected to reach 662 degrees F (350 degrees C)
and higher. During inhalation, the air temperature might be reduced to
between 360 degrees F and 302 degrees F (182 degrees C and 150 degrees C
[respectively]) by the time the air reached the larynx"

They also mention the wet towel, although they talk about things
that aren't safety related (apparently only the HCN is what we care
about for the wet towel):

€œWet towels will filter out smoke particles, acid gases such as
hydrogen chloride and hydrogen fluoride, and hydrogen cyanide.
Breathing through clothing will also filter out smoke particles,
but it will be less effective in filtering out acid gases
and hydrogen cyanide. Neither a wet towel nor clothing will
filter out carbon monoxide.€�

As an aside, they mentioned that slowing down people for one
second could cost one life, so, you don't want incapacitated
people blocking the aisles.

On Fri, 16 May 2014 05:19:33 +0200, nestork wrote:

I agree with BobF; the wet cloth acts like a filter for both smoke
particles and fumes that would be soluble in water.

Until I read the referenced articles, I would also have believed that
filtering the smoke itself might have been a key safety issue.

But, we don't have any proof yet that smoke particles are anything
we care about from an inhalation standpoint during a cabin fire.

In fact, this detailed article about all the negative effects of
a fire mainly discuss "smoke density" as a visual impairment factor,
and not as a critical inhalent (see page 39 of 47):

"Compilation of Data on the Sublethal Effects of Fire Effluent"
http://fire.nist.gov/bfrlpubs/fire09/PDF/f09033.pdf

What we seem to care about is hydrogen cyanide, which is soluble
in water. So the web towel apparently absorbs the HCN before you do.

On page 19 of 47, there is a table of the results of experiments
of HCN gases on a variety of mammals, since they say only one
human study was ever done. However, it's hard for me to
extrapolate that table to what happens in a real cabin fire.

So, what we really need is the key datapoint:
a. What is the concentration of HCN in a typical aircraft fire?

Ann Marie Brest wrote:
On Fri, 16 May 2014 05:19:33 +0200, nestork wrote:

I agree with BobF; the wet cloth acts like a filter for both smoke
particles and fumes that would be soluble in water.

Until I read the referenced articles, I would also have believed that
filtering the smoke itself might have been a key safety issue.

But, we don't have any proof yet that smoke particles are anything
we care about from an inhalation standpoint during a cabin fire.

A friend of mine was hospitalized for smole inhalation. They would come in
regularly and pound the hell out of his chest to break loose the crud in his
lungs so the body could try to eliminate it. Inhaled particulate matter can
without a doubt do significant damage.

On Thu, 15 May 2014 21:46:22 -0700, Bob F wrote:

Inhaled particulate matter can without a doubt do significant damage.

I would tend to wish to agree, since we've all heard about firefighters
being treated for "smoke inhalation".

However, if particulates were a thread to life, why wouldn't the FAA
and the other cabin fire articles previously posted mention smoke
particles as anything more than an irritant?

Science, being what science is, doesn't always agree with our gut
feelings.

On Thu, 15 May 2014 16:46:21 -0700, Ann Marie Brest
wrote:

I'm not sure WHERE to ask this, but, how does a wet cloth
work in an airplane crash anyway?

Why do they always boil water when a baby is coming?

Do babies drink coffee?

(on TV)

In step 3 at 45 seconds into this video shows it in use:
http://www.youtube.com/watch?v=RXaTt...etailpage#t=49

What's the wet cloth (scientifically) doing?

On Fri, 16 May 2014 03:26:21 +0000 (UTC), Ann Marie Brest
wrote:

On Thu, 15 May 2014 20:16:19 -0400, Frank wrote:

What's the wet cloth (scientifically) doing?
http://www.faa.gov/pilots/safety/pil.../Smoke_Web.pdf

That nicely summarized FAA article explains:
- Smoke is a complex of particulate matter, invisible combustion gases & vapors suspended in the fire atmosphere.
- Inhalation of toxic gases in smoke is the primary cause of fatalities
- Carbon monoxide & hydrogen cyanide are the principal toxic combustion gases
- Carbon monoxide combines with the hemoglobin in blood and interferes with the oxygen supply to tissues
- Hydrogen cyanide inhibits oxygen utilization at the cellular level.
- Carbon dioxide is a relatively innocuous fire gas, increases respiration rate causing an increase in the uptake of other combustion gases
- Irritant gases, such as hydrogen chloride and acrolein, are generated from burning wire insulation
- Generally, carbon dioxide levels increase while oxygen concentrations decrease during fires.

And then finally, the article suggests:
- Cloth held over the nose and mouth will provide protection from smoke particulates;
- If the cloth is wet, it will also absorb most of the water-soluble gases (i.e., hydrogen cyanide & hydrogen chloride).

Wow. That's good to have suggested. I certainly don't need any HCn or
HCl.

What's interesting is that the entire article doesn't discuss any dangers
of breathing smoke particulates, so, why it bothers to mention a dry cloth
is perplexing since we can safely assume that filtering out particulates is
merely a convenience,

How can we safely assume that? I'd assume the opposite.

and not a safety issue.

I think what you have is a 3-page** article where they decided to be
brief and not emphasize every problem. It's meant as advice and not a
scientific paper, so they've taken a short, clear-cut approach.

**Less than 3, given the pictures and the line spacing.

So, now we're left with the a WET cloth absorbing water-soluble gases.
Of the two water-soluble gases, only hydrogen cyanide was listed in
the article as being a safety issue (the other water-soluble gas was
merely an irritant).

Irritants irritate me. Anyhow, when HCl mixes with water it turns
into hydrocholoric acid, one of the stronger acids. I don't want that
in my lungs.


So, I guess we finally have the answer to "why the wet cloth?".

The WET CLOTH filters out (water soluble) hydrogen cyanide:
"Hydrogen cyanide poisoning signs & symptoms are weakness, dizziness, headache,
nausea, vomiting, coma, convulsions, & death. Death results from respiratory arrest.
Hydrogen cyanide gas acts rapidly. Symptoms & death can both occur quickly."

Yes, that's how they kill people in the gas chamber.

On Fri, 16 May 2014 05:19:33 +0200, nestork
wrote:


I agree with BobF; the wet cloth acts like a filter for both smoke
particles and fumes that would be soluble in water.

During World War One, Canadian soldiers being attacked with chlorine gas
(called "Mustard Gas" at the time because of it's yellow-green colour)
were told to urinate into their handkerchiefs and to breathe through

Hey, finally a benefit from my prostate problems. And truly, I was
just now wondering where to get water for the wet cloth.

that wet cloth. The chlorine gas would dissolve in the water as it
passed through the handkerchief, thereby keeping our troops safe and
alive.

Do you remember Everett Dirkson and how he talked. I read many years
ago that that was from being gassed in WWI, not enough to be killed
obviously. Couldn't find a trace about that on the web, even though
wikip or something remarked on his voice.

On Fri, 16 May 2014 04:33:21 +0000 (UTC), Ann Marie Brest
wrote:

On Fri, 16 May 2014 05:19:33 +0200, nestork wrote:

I agree with BobF; the wet cloth acts like a filter for both smoke
particles and fumes that would be soluble in water.

Until I read the referenced articles, I would also have believed that
filtering the smoke itself might have been a key safety issue.

But, we don't have any proof yet that smoke particles are anything
we care about from an inhalation standpoint during a cabin fire.

I think we're allowed to take judicial notice of everything else we've
learned in our lives.

It is frequenty reported that someone dies of smoke inhalation. That's
certainly something to care about. It may take longer than dying from
cynanide, but it's still bad.

I'm pretty sure the amount of cyanide varies widely from one airplane
fire to another, but there is no time to measure it.

In fact, this detailed article about all the negative effects of
a fire mainly discuss "smoke density" as a visual impairment factor,
and not as a critical inhalent (see page 39 of 47):

"Compilation of Data on the Sublethal Effects of Fire Effluent"
http://fire.nist.gov/bfrlpubs/fire09/PDF/f09033.pdf

What we seem to care about is hydrogen cyanide, which is soluble
in water. So the web towel apparently absorbs the HCN before you do.

On page 19 of 47, there is a table of the results of experiments
of HCN gases on a variety of mammals, since they say only one
human study was ever done. However, it's hard for me to
extrapolate that table to what happens in a real cabin fire.

So, what we really need is the key datapoint:
a. What is the concentration of HCN in a typical aircraft fire?

Who says there is a typical aircraft fire wrt HCN?

On Fri, 16 May 2014 04:00:28 +0000 (UTC), Ann Marie Brest
wrote:

On Fri, 16 May 2014 03:52:45 +0000, Ann Marie Brest wrote:

Armed with the new keywords "wet cloth hydrogen cyanide", I find more
on the toxicity of HCN over he

This flight safety PDF titled "Guarding the airways", is of interest:
http://flightsafety.org/download_fil...t06_p28-30.pdf

It mentions only that the "wet cloth" prevents irritation, which we're
not concerned with in this discussion.

Speak for yourself, John.

On 05/15/2014 11:26 PM, Ann Marie Brest wrote:
What's interesting is that the entire article doesn't discuss any dangers
of breathing smoke particulates, so, why it bothers to mention a dry cloth
is perplexing since we can safely assume that filtering out particulates is
merely a convenience, and not a safety issue.

Yes, a rag soaked in the proper solvent will perform better than a dry rag.
This is why you should have a properly labeled 4 oz bottle of dihydrogen monoxide in your carry on bag.

On Friday, May 16, 2014 6:59:29 AM UTC-4, Ann Marie Brest wrote:
On Thu, 15 May 2014 21:46:22 -0700, Bob F wrote:



Inhaled particulate matter can without a doubt do significant damage.



I would tend to wish to agree, since we've all heard about firefighters

being treated for "smoke inhalation".



However, if particulates were a thread to life, why wouldn't the FAA

and the other cabin fire articles previously posted mention smoke

particles as anything more than an irritant?



As others have said, they focused on the main cause of deaths in fires
and that is the gases. That doesn't mean that particles are not also
dangerous and life threatening. People that wind up hospitalized or die,
typically die from a combined effect of everything to their lungs, ie gases,
heat, particulate inhalation. It makes sense the gases are the most
serious, but if you had some exposure to toxic gases, would you rather
show up at the hospital with just that, or with your lungs full of soot
and the irritation from that too? Some of these people just barely survive
and whether they've inhaled particulates or not could make the difference.




Science, being what science is, doesn't always agree with our gut

feelings.

Just because someone writing a brief article doesn't specifically mention
something, doesn't constitute science.

On Fri, 16 May 2014 04:24:46 -0700, micky wrote:

..snip....
Why do they always boil water when a baby is coming?

Do babies drink coffee?

(on TV)

...snip...

LOL! just popped out for a spot of tea?

However the heat from the hot water and towels dilates the cervix really
fast, but does increase the risk of infection.

Years ago, newspapers were used too, because they were steam press rolled
and sterilized, but not today.

On 5/16/2014 8:29 AM, Hugh Briss wrote:

Yes, a rag soaked in the proper solvent will perform better than a dry rag.
This is why you should have a properly labeled 4 oz bottle of dihydrogen
monoxide in your carry on bag.

You should know that inhaling that will kill you.
And at high temperatures, the vapors can be lethal,
also. And you want people to carry it on PLANES!
Shesh!.

For safety, all passengers should fly nude. Discounts
offered to cheerleaders squads who get frequent flier
miles.

--
..
Christopher A. Young
Learn about Jesus
www.lds.org
..

On Fri, 16 May 2014 07:34:02 -0400, micky wrote:

we can safely assume that filtering out particulates is
merely a convenience,

How can we safely assume that? I'd assume the opposite.

I also would have assumed the opposite, had I not read the
articles, which prove our assumptions invalid.

The other articles on cabin fires went into nice detail
as to how hydrogen cyanide acts as a cellular asphyxiant by
binding to mitochondrial cytochrome oxidase.

They explicitly stated that smoke particles are not
deadly in an airplane crash.

So, what you, or I, would have assumed about smoke itself
being deadly, is apparently wrong.

If you still think your (and my) initial assumption is right,
then what we need is an article about cabin fires which says
both that the smoke particles are deadly, and, that a wet
cloth reduces them.

Otherwise, we're just making non-scientific assumptions.

On Fri, 16 May 2014 05:46:19 -0700, trader_4 wrote:

Just because someone writing a brief article doesn't specifically
mention something, doesn't constitute science.

Science isn't what you are I guess.
Science is what can be tested & proven.

I'd be glad if you can find a tested/proven article on airplane fires
which says that smoke particles, in and of themselves, constitute a
life-threatening danger in the time it takes to exit a burning airplane.

We found more than a half dozen sources, including scientific papers,
none of which said that the smoke particles were the immediate danger in
cabin fires - nor did we find anything that said a wet cloth filters them
out.

If we are to assume smoke particles are a life-threatening danger, we'd
have to find at least one scientific article that said that the
particulate matter itself could kill us in the time of a cabin fire.

Even then, we'd have to know that a wet towel would filter out those
particles.

I looked for papers backing up our (apparently erroneous) assumptions.
I can't find any.

On Fri, 16 May 2014 07:48:32 -0400, micky wrote:

I'm pretty sure the amount of cyanide varies widely from one airplane
fire to another, but there is no time to measure it.

I agree that we don't have actual ppm levels documented yet, but,
we do know that the hydrogen cyanide gas is deadly within minutes.

One of the papers said death ensues within minutes.

Another one discussed how a hundred people died, none of whom
had traumatic injury, all of whom died from the toxicity of
the gases in the fire.

What we don't know is the ppm concentration REDUCTION that
a wet towel provides us.

On 05/16/2014 05:15 AM, Stormin Mormon wrote:
On 5/16/2014 8:29 AM, Hugh Briss wrote:

Yes, a rag soaked in the proper solvent will perform better than a dry rag.
This is why you should have a properly labeled 4 oz bottle of dihydrogen
monoxide in your carry on bag.

You should know that inhaling that will kill you.
And at high temperatures, the vapors can be lethal,
also. And you want people to carry it on PLANES!
Shesh!.


DHMO also contributes to severe weather and flash flooding.

micky wrote:
So, what we really need is the key datapoint:
a. What is the concentration of HCN in a typical aircraft fire?

Who says there is a typical aircraft fire wrt HCN?

Maybe we should use natural materials in airplane interiors.

Understanding CO and HCN is especially crucial to today's fire service, because
the smoke that firefighters were exposed to 20 or 30 years ago is not the same
as it is today. Wood, cellulose, cotton, silk, wool, etc., were bad decades ago,
but they were nowhere near as toxic as the chemically-manufactured materials of
today. When combined in a fire situation, these chemicals are often referred to
as "the breath from hell"2 and include compounds such as:
a.. Acetyls-aerosol containers, combs, lighters and pens
b.. Acrylics-glues, food packages and skylights
c.. Nylons-various household containers, brushes, sewing thread and fishing
line
d.. Polyesters-hair dryers, computers and kitchen appliances
e.. Polypropylene-bottles, diapers and furniture
f.. Polyurethanes-shoes and cushions
g.. Polyvinyl chlorides (PVC)-carpet, clothes, purses, records and shower
curtains
h.. Thermo sets-TVs, coatings, toilets, buttons, flooring and insulation
http://www.firefighternation.com/art...more-dangerous

On 5/16/2014 9:15 AM, Stormin Mormon wrote:


For safety, all passengers should fly nude. Discounts
offered to cheerleaders squads who get frequent flier
miles.


Looking around right now, including looking in a mirror, I'd want a
blindfold! I'm willing to make exceptions, but most of the time, a
blindfold would keep you from getting an upset tummy.

On Fri, 16 May 2014 06:51:56 -0700, Ann Marie Brest
wrote:

...snip...
The other articles on cabin fires went into nice detail
as to how hydrogen cyanide acts as a cellular asphyxiant by
binding to mitochondrial cytochrome oxidase.

They explicitly stated that smoke particles are not
deadly in an airplane crash.

So, what you, or I, would have assumed about smoke itself
being deadly, is apparently wrong.

If you still think your (and my) initial assumption is right,
then what we need is an article about cabin fires which says
both that the smoke particles are deadly, and, that a wet
cloth reduces them.

Otherwise, we're just making non-scientific assumptions.


Was there any mention of the radiated heat from these fires? After
personally experiencing a major fire in a building adjacent to our home, I
learned to apprecaite that aspect. For certain, a wet cloth over the head
would help shield. To see the potential shielding just envision sticking
your head into a barbecue pit with, and without, the wet towel. The air
into your lungs gets cooled so won't sear as much and at least your
corneas should remain intact.

On Thu, 15 May 2014 20:19:33 -0700, nestork
wrote:


I agree with BobF; the wet cloth acts like a filter for both smoke
particles and fumes that would be soluble in water.

During World War One, Canadian soldiers being attacked with chlorine gas
(called "Mustard Gas" at the time because of it's yellow-green colour)
were told to urinate into their handkerchiefs and to breathe through
that wet cloth. The chlorine gas would dissolve in the water as it
passed through the handkerchief, thereby keeping our troops safe and
alive.

I also heard that in the field urinate upon a 'dirty' wound to wash it,
because urine is more sanitary than all that muck in there.

Also, heard good for jelly fish sting, at least appears in some films as
such.

On Fri, 16 May 2014 07:26:48 -0700, Ed Pawlowski wrote:

On 5/16/2014 9:15 AM, Stormin Mormon wrote:


For safety, all passengers should fly nude. Discounts
offered to cheerleaders squads who get frequent flier
miles.


Looking around right now, including looking in a mirror, I'd want a
blindfold! I'm willing to make exceptions, but most of the time, a
blindfold would keep you from getting an upset tummy.

LOL! and now the Europeans have caught our 'fat' virus!

Per RobertMacy:
I also heard that in the field urinate upon a 'dirty' wound to wash it,
because urine is more sanitary than all that muck in there.

Also, heard good for jelly fish sting, at least appears in some films as
such.

With the caution that that only applies to your own jelly fish sting...
or, at least, a sting on somebody you know really, really well.... -)
--
Pete Cresswell

On 5/15/2014 11:26 PM, Ann Marie Brest wrote:
On Thu, 15 May 2014 20:16:19 -0400, Frank wrote:

What's the wet cloth (scientifically) doing?
http://www.faa.gov/pilots/safety/pil.../Smoke_Web.pdf

That nicely summarized FAA article explains:
- Smoke is a complex of particulate matter, invisible combustion gases & vapors suspended in the fire atmosphere.
- Inhalation of toxic gases in smoke is the primary cause of fatalities
- Carbon monoxide & hydrogen cyanide are the principal toxic combustion gases
- Carbon monoxide combines with the hemoglobin in blood and interferes with the oxygen supply to tissues
- Hydrogen cyanide inhibits oxygen utilization at the cellular level.
- Carbon dioxide is a relatively innocuous fire gas, increases respiration rate causing an increase in the uptake of other combustion gases
- Irritant gases, such as hydrogen chloride and acrolein, are generated from burning wire insulation
- Generally, carbon dioxide levels increase while oxygen concentrations decrease during fires.

And then finally, the article suggests:
- Cloth held over the nose and mouth will provide protection from smoke particulates;
- If the cloth is wet, it will also absorb most of the water-soluble gases (i.e., hydrogen cyanide & hydrogen chloride).

What's interesting is that the entire article doesn't discuss any dangers
of breathing smoke particulates, so, why it bothers to mention a dry cloth
is perplexing since we can safely assume that filtering out particulates is
merely a convenience, and not a safety issue.

So, now we're left with the a WET cloth absorbing water-soluble gases.
Of the two water-soluble gases, only hydrogen cyanide was listed in
the article as being a safety issue (the other water-soluble gas was
merely an irritant).

So, I guess we finally have the answer to "why the wet cloth?".

The WET CLOTH filters out (water soluble) hydrogen cyanide:
"Hydrogen cyanide poisoning signs & symptoms are weakness, dizziness, headache,
nausea, vomiting, coma, convulsions, & death. Death results from respiratory arrest.
Hydrogen cyanide gas acts rapidly. Symptoms & death can both occur quickly."


If I'm in a burning about to crash plane, I think the last thing I would
worry about would be the smoke

On Fri, 16 May 2014 07:24:46 -0400, micky
wrote:

On Thu, 15 May 2014 16:46:21 -0700, Ann Marie Brest
wrote:

I'm not sure WHERE to ask this, but, how does a wet cloth
work in an airplane crash anyway?

Why do they always boil water when a baby is coming?

Something to keep the father occupied and out of the way.


Do babies drink coffee?

(on TV)

In step 3 at 45 seconds into this video shows it in use:
http://www.youtube.com/watch?v=RXaTt...etailpage#t=49

What's the wet cloth (scientifically) doing?

On Fri, 16 May 2014 08:09:03 -0700, RobertMacy
wrote:

On Thu, 15 May 2014 20:19:33 -0700, nestork
wrote:


I agree with BobF; the wet cloth acts like a filter for both smoke
particles and fumes that would be soluble in water.

During World War One, Canadian soldiers being attacked with chlorine gas
(called "Mustard Gas" at the time because of it's yellow-green colour)
were told to urinate into their handkerchiefs and to breathe through
that wet cloth. The chlorine gas would dissolve in the water as it
passed through the handkerchief, thereby keeping our troops safe and
alive.

I also heard that in the field urinate upon a 'dirty' wound to wash it,
because urine is more sanitary than all that muck in there.

Unless one has a urinary tract infection, urine is sterile, aiui**.

I think that means two bottles of urine can't make a baby.

**so you're right.

Also, heard good for jelly fish sting, at least appears in some films as
such.

On Friday, May 16, 2014 9:51:56 AM UTC-4, Ann Marie Brest wrote:
On Fri, 16 May 2014 07:34:02 -0400, micky wrote:



we can safely assume that filtering out particulates is

merely a convenience,



How can we safely assume that? I'd assume the opposite.



I also would have assumed the opposite, had I not read the

articles, which prove our assumptions invalid.



Your making all kinds of bizarre leaps here. Just because inhalation
of smoke particles during a fire isn't mentioned as deadly or the
major cause of fatalities, doesn't mean that it's just an inconvenience.
Some people die just from an asthma attack, so it seems entirely
possible that inhaling soot could be a factor in whether somone survives
or not. Most serious fire victims are going to have heat, gas, and
particle inhalation and I would expect that you could have patients
that survive because they didn't have the additional burden of the
particles, while others that did inhale it die. The leading cause,
the thing to be most worried about, etc is still the gases and heat,
but that doesn't mean particle inhalation is just an inconvenience.


The other articles on cabin fires went into nice detail

as to how hydrogen cyanide acts as a cellular asphyxiant by

binding to mitochondrial cytochrome oxidase.



They explicitly stated that smoke particles are not

deadly in an airplane crash.



IDK what other article you're talking about. Link?



So, what you, or I, would have assumed about smoke itself

being deadly, is apparently wrong.



If you still think your (and my) initial assumption is right,

then what we need is an article about cabin fires which says

both that the smoke particles are deadly, and, that a wet

cloth reduces them.



Otherwise, we're just making non-scientific assumptions.

http://www.fireengineering.com/artic...nhalation.html

So far, all I see is you making wild assumptions. You're taking
a fire guide for idiots from the FAA, as a scientific source.
It's not. It's a layman's guide. It also looks like it could have
been written in the 50's or 60's. And then you infer that because
they don't say something, that means that soot inhalation is not
a serious, possibly life threatening factor? It's just an inconvenience?

Here, from Fire Engineering. Not exactly a medical authority, but
it is a lot more detailed as to the effects.

"Autopsy and experimental data show that serious injury and death result from exposure to contact irritants, primarily hydrogen chloride, and the central systemic poisons, carbon monoxide (CO) and cyanide.1 Contact irritants cause cellular damage and death. In response to irritants, cells release fluids, causing massive edema. Additional inflammatory responses cause cells to lose integrity and die.2

Systemic poisons are absorbed into the blood through the lungs. They act on specific cells in the body or within specific parts of every cell. Systemic poisons either inhibit critical cell functions or cause cellular death.

Contact irritants include particulate matter such as soot. Particles larger than five microns will lodge in the upper airways, causing mechanical obstruction. They are observed in the nose and the mouth. Particles smaller than one micron are inhaled deep into the lungs, where the carbonaceous soot is toxic to the macrophages. Macrophages are cells that remove foreign particles. Heavy metals coating the surface of soot cause direct lung damage by forming free oxygen radicals which damage cilia and alveolar surfaces."

That doesn't sound like just an inconvenience.

On Fri, 16 May 2014 08:05:39 -0700, RobertMacy wrote:

Was there any mention of the radiated heat from these fires?

Yes.

We noted that this flight safety PDF, which was all about
protecting your airways in a cabin fire, explicitly said
that the dry heat of a cabin fire isn't a major concern
when it comes to protecting your breathing airways:
http://flightsafety.org/download_fil...t06_p28-30.pdf

As already noted, they said, verbatim:
"the human body¢s upper airway naturally provides significant
protection to the lower airway and lungs against extreme
heat from hot, dry air."

Absolutely none of the air-safety PDFs yet mentioned *anything*
about the wet cloth having anything to do with cooling hot
air, so, we can safely assume the only *safety* purpose of
the wet cloth is to trap some of the hydrogen cyanide gas.

On Fri, 16 May 2014 08:05:39 -0700, RobertMacy wrote:

For certain, a wet cloth over the head
would help shield. To see the potential shielding just envision sticking
your head into a barbecue pit with, and without, the wet towel. The air
into your lungs gets cooled so won't sear as much and at least your
corneas should remain intact.

I used to think that jumping up into the air when an elevator
crashes to the ground, would stop me from crashing along with
it. It's not supported by the facts.

Neither is the theory that the wet cloth is there to protect
us from the heat of the air during a cabin fire supported by
*any* of the flight-safety references we have so far been able
to find.

Sounds good. I'd believe it myself, if I was just guessing.

But, there's *nothing* in those flight-safety PDFs that says
that the wet cloth protects against heat in a cabin fire.

Now that's not to say that a cabin fire isn't *hot*.
For example, this previously listed PDF shows the temperatures
that can be reached in the cabin during a fuel-fed fire are
extremely *HOT!*.

http://wenku.baidu.com/view/8abb4621...fcc220e6f.html
"In an aircraft accident that involves a fuel-fed fire, cabin air
temperatures could be expected to reach 662 degrees F (350 degrees C)
and higher. During inhalation, the air temperature might be
reduced to between 360 degrees F and 302 degrees F
(182 degrees C and 150 degrees C [respectively]) by the time
the air reached the larynx"

That article mentions that the wet cloth might filter out
smoke particles (which don't seem to be an immediate danger),
but it doesn't even hint at that wet cloth cooling down the
air.

So, unless someone comes up with a good reference, I think we
can safely say that the *assumption* that the wet cloth is
there to cool down the air breathed in a cabin fire is a false
assumption (however good it seems to "sound" to most of us).

On Fri, 16 May 2014 05:50:29 -0700, RobertMacy
wrote:

On Fri, 16 May 2014 04:24:46 -0700, micky wrote:

..snip....
Why do they always boil water when a baby is coming?

Do babies drink coffee?

(on TV)

...snip...

LOL! just popped out for a spot of tea?

However the heat from the hot water and towels dilates the cervix really
fast, but does increase the risk of infection.

Are you serious? (real question, no exasperation intended)

They poured the hot water in her to dilate the cervix?????? What do
they do when they're not in a farm house in 1920? Same thing?

Years ago, newspapers were used too, because they were steam press rolled
and sterilized, but not today.