Some Guy wrote:
George wrote:

Next time watch the significant difference on how medical use vs
other tanks are filled. Any medical use tanks are first evacuated
to insure there is nothing else in the tank before it is filled.

How exactly could something get into the tank in the first place?

If it's connected to a manifold system, then yes, the gas from a
higher-pressure tank could flow into it. But doesn't that
higher-pressure tank already contain known-pure O2?

If it's never connected to a manifold system or to another tank, then
how exactly could something get into it? Deliberate tampering?

If the other tank contained, say, acetylene.

In article , Jim Yanik wrote:
(Doug Miller) wrote in
:

In article , Steve
Barker wrote:
On 6/19/2010 8:01 AM, Doug Miller wrote:
In articleSK2dnRfBjvQiJ4HRnZ2dnUVZ_oWdnZ2d@giganews. com,
Steve wrote:
On 6/18/2010 8:58 PM, Some Guy wrote:
Is there any difference between a tank of welding oxygen vs
medical oxygen as far as purity, concentration, hazardous
impurities, etc, that would render welding oxygen insufficient (or
even dangerous) for helping to supplement breathing / respiration
?

it's the same.

Ummm..... no, it's not. Read the other responses in this thread from
people who actually know the difference.

i read the responses. It's the same.

So the people who said it's not the same are wrong?


the people who said they're different said it a long time ago when they
actually were different.
Times have changed,they no longer actually are different.

Uh-huh. Right. Welding oxygen is certified just as pure as medical oxygen, no
contaminants. Suuuurrrrre it is. That's why they use welding oxygen in
hospitals.

Jay Hanig wrote:

On 6/18/2010 11:56 PM, Some Guy wrote:
AZ Nomad wrote:
Even welding supply stores will stock only "medical grade" oxygen?

You people might want to read this:

http://www.avweb.com/news/pelican/182079-1.html

*That* was a great article. The writer has great credibility to my
mind, as I am a registered nurse, former scuba instructor, and former
commercial pilot. I thought I knew a lot about oxygen. It turns out I
wasn't as well informed as I had assumed.

You guys really need to read this if you're interested in compressed
oxygen in any form.

Jay

The purity standard for welding O2 is higher than the purity standard
for medical O2. In reality all three normal grades you can get, welding,
medical and aviator exceed all of the standards. Only the analytical
grade is higher purity.

Ed Pawlowski wrote:

"Some Guy" wrote in message ...
Ed Pawlowski wrote:

Certification. Medical oxygen has to be certified to a certain
purity, welding does not.

How exactly can compressed oxygen be "impure" ?

Are some oxygen molecules more pure than other oxygen molecules?

The content of bottled oxygen is not 100% pure. It is 99.xxx% pure. That
other tiny amount can be anything in the atmosphere or it can be some
contaminant from the bottle. I used to work with medical oxygen and every
batch had a certification giving the purity.


Or does the Medical oxygen tank look nicer and cleaner than the Welding
oxygen tank?

You pay for that test and the potential liability that goes
along with it.

I think you pay more for medical and aviation O2 because the
consequences can be more expensive if there is a problem with the
product (the product being compressed oxygen).

That is what I just said above.

The product itself is no
more expensive or different or has any additional processing steps done
to it on the basis of it's sale in it's variously-labelled forms.

It has a step that does not have to be taken with welding oxygen.
Certification. O2 tanks have been contaminated in the past. Rare, but it
has happened. Filling my own tanks, I'd not be concerned about using
welding oxygen, but I'm not so quick to grab a tank off the back of a truck
at a job site and start breathing it. If you get the certification with
welding grade, then it is the same. That piece of paper is worth a lot of
money if there ever was a problem.



Medical 99.95% pure
Welding 99.99% pure

On Sat, 19 Jun 2010 22:27:17 -0500, Pete C. wrote:

The purity standard for welding O2 is higher than the purity standard
for medical O2. In reality all three normal grades you can get, welding,
medical and aviator exceed all of the standards. Only the analytical
grade is higher purity.

Nope. Why don't you look it up, starting with 1) the percentage of oxygen
and ending with 2) the levels of impurities.

You can't use welding O2 for medical purposes but you can use medical O2
for welding.

On 6/19/2010 10:02 PM, Doug Miller wrote:

Uh-huh. Right. Welding oxygen is certified just as pure as medical oxygen, no
contaminants. Suuuurrrrre it is. That's why they use welding oxygen in
hospitals.


There is a LOT of **** done in hospitals simply because that is the way
they've always done it. To suggest otherwise to them will get you a
look that suggests you've lost your mind.

I deal with policies all the time that closer examination would reveal
are outdated and kind of stupid if you consider the current realities.
But the Powers That Be know what they know and nobody can tell them
different. So we still do what we've always done.... because we've
always done it that way.

A lawyer would probably make a big deal about "welding" oxygen instead
of USP in much the same way the US Navy made a big deal about the
captain of the USS Indianapolis not zigzaging when his ship was
torpedoed. The commander of the Japanese submarine testified at his
court martial that it wouldn't have mattered one way or the other; he
still would have nailed him. The Navy didn't care... because policy
stated you should always zigzag when submarines might be around. After
all, they'd always done it that way.

Many of the folks who determine these policies are dinosaurs, and about
as current.




Jay

On 6/19/2010 8:05 PM, wrote:

Acetylene in an oxygen tank is a bomb.
It could get contaminated by bacteria from the "breathing" that
happens when you leave the valve open but most real welders will turn
the tank back in with a little pressure in it, Same for SCUBA folks.




You typically never allow the pressure to drop to zero because higher
pressure in the tank is the only way to keep ambient moisture from
entering the tank. Ultimately it's to keep the tank from rusting on the
inside.




Jay

"Jay Hanig" wrote in message
...
On 6/19/2010 8:05 PM, wrote:

Acetylene in an oxygen tank is a bomb.
It could get contaminated by bacteria from the "breathing" that
happens when you leave the valve open but most real welders will turn
the tank back in with a little pressure in it, Same for SCUBA folks.




You typically never allow the pressure to drop to zero because higher
pressure in the tank is the only way to keep ambient moisture from
entering the tank. Ultimately it's to keep the tank from rusting on the
inside.




Jay

That is exactly why medical oxygen thanks have to be evacuated. Rare that
one would come back with any pressure at all.

On 6/19/2010 8:19 AM, LSMFT wrote:
Some Guy wrote:
Tom Horne wrote:

Is there any difference between a tank of welding oxygen vs
medical oxygen (...)

And just to be clear -

Welding oxygen is more (way more) than just compressed "air".
And what I mean by "air" is the stuff that's all around us
right now.

Yes?

To be precise it is way less. The air we breath is roughly twenty
percent oxygen.

And what I meant by "way more" was that welding oxygen has a higher
oxygen content (or oxygen concentration) vs ordinary air. So I don't
know why you'd say it's "way less".

Medical oxygen is nearly one hundred percent oxygen.

And likewise for welding oxygen - yes?

Harry K wrote:

Yes there is a difference according to my first aid training (years
ago). You can use in the case of emergency. It is IIRC too dry to
use for extended periods (I should have paid more attention to that
discussion).

From what I've been reading tonight, ALL forms of compressed oxygen
(Aviation, Medical, Welding) come from the SAME source (a tank of Liquid
Oxygen - LOX) and are transfered to variously labelled tanks and charged
various prices based on the label on the tank.

My guess is that the price differential is caused by liability insurance
and the need to recoup that cost based on the end-use of the gas. The
insurance industry might perceive that aviation oxygen (as a product)
carries the highest risk to the producer / seller, with medical oxygen
less risky, and welding oxygen the lowest risk. Risk in this context
means what sort of incident could happen if the wrong gas is
accidentially sold to the end user, or could happen if the tank fails.

The humidity of compressed oxygen seems to be a red herring. In medical
situations such as the hospital bedside, oxygen supply lines are passed
through a bubbler or some other humidification device to add humidity to
the air. This is a stationary situation where the person is likely to
be on the air supply for an extended period, and humidification is done
more for comfort or to prevent airway irritation than anything else. In
other medical situations (EMS O2 respirator tanks) the air is dry -
because it simply can't supply O2 for an extended period anyways.

And you don't want to get water in your high-pressure tanks anyways - if
only so they don't rust.

Aviation air also can't contain a lot of humidity because (or so the
story goes) the water could freeze at high altitudes and mess up the
supply and metering lines.

So the bottom line is that if you walk into a welding supply store to
buy an oxygen tank, don't let on that you intend to use it to fill your
plane's on-board tank, or you want to make an oxygen tent for your sick
pet. The guy behind the counter will most likely go ape-**** and either
deny your purchase, or force you to buy the more expensive tank -
probably because their insurance company forces them to do that.

The insurance industry plays a far larger role behind the scenes in our
daily lives than we realize. The products we can buy, the services we
use, the way they are delivered or sold to us, etc, exist because the
manufacterers, retails or providers have reached a stable (perhaps even
strained) coexistance with the insurance industry.

Seems like my dad had a machine that created (or condensed) oxygen from
the air for him to breath. No bottles to change.
Why can't they do that for welding?



They do and they aren't an unusual thing at all to find in a low-medium
usage shop.

Ed Pawlowski wrote:

You typically never allow the pressure to drop to zero because
higher pressure in the tank is the only way to keep ambient
moisture from entering the tank. Ultimately it's to keep the
tank from rusting on the inside.

That is exactly why medical oxygen thanks have to be evacuated.
Rare that one would come back with any pressure at all.

I would think the contrary.

O2 tanks used by hospitals are more likely to be part of a manifold
system, and as such will always be maintained at some positive pressure
by virtue of the fact that at least one of their "gang-mates" is likely
to have enough excess pressure to keep them partially pressurized.

If a gang of O2 tanks at a hospital collectively fall below some
acceptible level of pressure, then they're no longer useful as an air
souce and MUST be changed out. So again the argument here is that
medical O2 tanks are MORE likely to be returned while still containing
some positive pressure charge.

If the strongest argument so far is that a "medical-grade" tank of O2
has lived it's life with minimal to zero infiltration of atmospheric
humidity (or even nitrogen) compared to a welding tank, then that's a
pretty weak argument to say that a tank of welding O2 is unhealthy to
breath. Last I checked, we all take in some some water vapor and
nitrogen when we breath standard air.

In other words, a lack of "purity" does not equal unhealthy or hazardous
for human breathing. A lack of purity (it seems) will degrade welding
performance, maybe mess up equipment, etc.

And so far, it's just been pure speculation here that tanks of welding
O2 are *not* evacuated prior to filling, just as supposedly medical
tanks are.

AZ Nomad wrote:

Nope. Why don't you look it up, starting with 1) the percentage
of oxygen and ending with 2) the levels of impurities.

Like I just said, the presence of impurities does not necessarily equate
to medical safety or have a health impact. If those impurities are
nitrogen or water vapor, then what exactly are the health implications
of those? We freeking breath them all the time - in concentrations
several orders of magnitude higher than what could possibly exist in a
tank of welding O2.

You can't use welding O2 for medical purposes

Says who?

A lawyer? Or a biochemist?

"Pete C." wrote:

Medical 99.95% pure
Welding 99.99% pure

Here's the problem I have with that.

What is the compressed gas supplier doing differently that would result
in that very slight (but consistent?) difference between those two
products?

If he has two machines or processes for creating the two products
(welding O2 and medical O2) and if the welding O2 product is more
"pure", then why would he operate two processes instead of simply using
a single process (the higher purity process) to create *both* of them?
Especially since the welding product is retailed at a lower price to
start with.

On 6/20/2010 7:54 AM, Some Guy wrote:
Ed Pawlowski wrote:

You typically never allow the pressure to drop to zero because
higher pressure in the tank is the only way to keep ambient
moisture from entering the tank. Ultimately it's to keep the
tank from rusting on the inside.

That is exactly why medical oxygen thanks have to be evacuated.
Rare that one would come back with any pressure at all.

I would think the contrary.

O2 tanks used by hospitals are more likely to be part of a manifold
system, and as such will always be maintained at some positive pressure
by virtue of the fact that at least one of their "gang-mates" is likely
to have enough excess pressure to keep them partially pressurized.

If a gang of O2 tanks at a hospital collectively fall below some
acceptible level of pressure, then they're no longer useful as an air
souce and MUST be changed out. So again the argument here is that
medical O2 tanks are MORE likely to be returned while still containing
some positive pressure charge.

If the strongest argument so far is that a "medical-grade" tank of O2
has lived it's life with minimal to zero infiltration of atmospheric
humidity (or even nitrogen) compared to a welding tank, then that's a
pretty weak argument to say that a tank of welding O2 is unhealthy to
breath. Last I checked, we all take in some some water vapor and
nitrogen when we breath standard air.

In other words, a lack of "purity" does not equal unhealthy or hazardous
for human breathing. A lack of purity (it seems) will degrade welding
performance, maybe mess up equipment, etc.

And so far, it's just been pure speculation here that tanks of welding
O2 are *not* evacuated prior to filling, just as supposedly medical
tanks are.

I can see a huge LOX tank next to a main traffic artery in the Southside
neighborhood of Birmingham where UAB Hospital is located. Tanker trucks
pull up next to the thing and fill it on a regular basis. The
maintenance guys who work for the complex tell me there are tunnels all
around under the place filled with all sorts of conduits and pipes that
distribute various electrons, liquids and gases that keep the hospital
alive. I imagine that LOX tank supplies O2 to the whole hospital and
perhaps a couple of different hospitals in the same general area. The
hospitals share doctors, why not oxygen?

TDD

The Daring Dufas wrote:

I can see a huge LOX tank next to a main traffic artery in the
Southside neighborhood of Birmingham where UAB Hospital is located.

LOX is a different situation. It requires a cryogenic storage tank, and
perhaps on-site re-compression to boost the pressure of the O2 that's
vaporized from the LOX as needed.

We're talking about the bottled O2 that's sold under variously-labelled
end-uses by the compressed gas retailer, and whether or not there's any
*real* negative health implications when using welding O2 gas instead of
"medical" O2 gas in a residential setting.

On 6/20/2010 8:32 AM, Some Guy wrote:
The Daring Dufas wrote:

I can see a huge LOX tank next to a main traffic artery in the
Southside neighborhood of Birmingham where UAB Hospital is located.

LOX is a different situation. It requires a cryogenic storage tank, and
perhaps on-site re-compression to boost the pressure of the O2 that's
vaporized from the LOX as needed.

We're talking about the bottled O2 that's sold under variously-labelled
end-uses by the compressed gas retailer, and whether or not there's any
*real* negative health implications when using welding O2 gas instead of
"medical" O2 gas in a residential setting.

It wouldn't surprise me if the LOX tank is used to fill portable tanks
for patient use. I'll have to ask one of my friends who works
maintenance at the hospital.

TDD

"Some Guy" wrote
That is exactly why medical oxygen thanks have to be evacuated.
Rare that one would come back with any pressure at all.

I would think the contrary.

O2 tanks used by hospitals are more likely to be part of a manifold
system, and as such will always be maintained at some positive pressure
by virtue of the fact that at least one of their "gang-mates" is likely
to have enough excess pressure to keep them partially pressurized.


You think wrong. Medical oxygen is used in many places aside from
hospitals. Thousands of bottle every day are used in private homes. They
are single size, no manifolds, They are generally used until empty.
Valves are left open, regulators removed. They are sometimes stored in poor
environments, must basements, trunk of a car, under the sink, laundry room.




If the strongest argument so far is that a "medical-grade" tank of O2
has lived it's life with minimal to zero infiltration of atmospheric
humidity (or even nitrogen) compared to a welding tank, then that's a
pretty weak argument to say that a tank of welding O2 is unhealthy to
breath. Last I checked, we all take in some some water vapor and
nitrogen when we breath standard air.

In other words, a lack of "purity" does not equal unhealthy or hazardous
for human breathing. A lack of purity (it seems) will degrade welding
performance, maybe mess up equipment, etc.




And so far, it's just been pure speculation here that tanks of welding
O2 are *not* evacuated prior to filling, just as supposedly medical
tanks are.

Not speculation. I've filled tanks. I followed the regulations.

"Ed Pawlowski" wrote in message
...

"Some Guy" wrote in message
...
Ed Pawlowski wrote:

Certification. Medical oxygen has to be certified to a certain
purity, welding does not.

How exactly can compressed oxygen be "impure" ?

Are some oxygen molecules more pure than other oxygen molecules?


The content of bottled oxygen is not 100% pure. It is 99.xxx% pure. That
other tiny amount can be anything in the atmosphere or it can be some
contaminant from the bottle. I used to work with medical oxygen and
every batch had a certification giving the purity.



Or does the Medical oxygen tank look nicer and cleaner than the Welding
oxygen tank?

You pay for that test and the potential liability that goes
along with it.

I think you pay more for medical and aviation O2 because the
consequences can be more expensive if there is a problem with the
product (the product being compressed oxygen).

That is what I just said above.


The product itself is no
more expensive or different or has any additional processing steps done
to it on the basis of it's sale in it's variously-labelled forms.

It has a step that does not have to be taken with welding oxygen.
Certification. O2 tanks have been contaminated in the past. Rare, but it
has happened. Filling my own tanks, I'd not be concerned about using
welding oxygen, but I'm not so quick to grab a tank off the back of a
truck at a job site and start breathing it. If you get the certification
with welding grade, then it is the same. That piece of paper is worth a
lot of money if there ever was a problem.

When I was a commercial deep sea diver, the oxygen we used in decompression
chambers was the same oxygen that we used for OA cutting. We did not use
medical oxygen.

Steve

visit my blog at http://cabgbypasssurgery.com

A fool shows his annoyance at once, but a prudent man overlooks an insult.

"The Daring Dufas" wrote

It wouldn't surprise me if the LOX tank is used to fill portable tanks
for patient use. I'll have to ask one of my friends who works maintenance
at the hospital.

TDD

LOX tanks fill LOX tanks. They can be filled for patient use of that is
what their supplier gives them. They are a different setup that using
compressed O2 though. Different tanks, regulators, etc. They are not
usually filled at hospital though, but by independent providers.

Compressed tanks either need mechanical pumps or, most home medical
suppliers use a cascade system of tanks increasing pressure into the smaller
tanks with each on up the line.

In article ,
"Ed Pawlowski" wrote:


You think wrong. Medical oxygen is used in many places aside from
hospitals. Thousands of bottle every day are used in private homes. They
are single size, no manifolds, They are generally used until empty.
Valves are left open, regulators removed. They are sometimes stored in poor
environments, must basements, trunk of a car, under the sink, laundry room.
Which is why there are requirements for cleaning the tanks before
filling. After that, you are on your own. Same with medicines, etc. They
have to be manufactured and stored pre-patient to certain conditions.


And so far, it's just been pure speculation here that tanks of welding
O2 are *not* evacuated prior to filling, just as supposedly medical
tanks are.

Not speculation. I've filled tanks. I followed the regulations.


Interestingly enough, this thread has gone on for as long as it has
w/o anyone mentioning the main danger of non-medical oxygen... That the
insurance company won't pay for it (g).

--
I want to find a voracious, small-minded predator
and name it after the IRS.
Robert Bakker, paleontologist

AZ Nomad wrote:

On Sat, 19 Jun 2010 22:27:17 -0500, Pete C. wrote:

The purity standard for welding O2 is higher than the purity standard
for medical O2. In reality all three normal grades you can get, welding,
medical and aviator exceed all of the standards. Only the analytical
grade is higher purity.

Nope. Why don't you look it up, starting with 1) the percentage of oxygen
and ending with 2) the levels of impurities.

You can't use welding O2 for medical purposes but you can use medical O2
for welding.

Nope, exactly the opposite.

"Some Guy" wrote
Like I just said, the presence of impurities does not necessarily equate
to medical safety or have a health impact. If those impurities are
nitrogen or water vapor, then what exactly are the health implications
of those?

But if the analysis does not say what the impurities are, you are trading on
dangerous ground. That welding tank may have been used along with any
other gas used in industrial environments.



You can't use welding O2 for medical purposes

Says who?

A lawyer? Or a biochemist?

Lawyers and other sensible people that do not know what other gas may be in
there. Oxygen falls into the same type of situation ad drugs. The active
ingredients of a pill are often a small percentage of the tablet, the rest
being inert ingredients. There are regulations on what those inert
ingredients can be. There are regulations on how they are handled.

If I was dying in an emergency situation from lack of oxygen, I'd grab any
tank available. If I was at home with COPD, I'd want to be sure that tank
was handled in a proper manner and would not make me worse off.

Some Guy wrote:

"Pete C." wrote:

Medical 99.95% pure
Welding 99.99% pure

Here's the problem I have with that.

What is the compressed gas supplier doing differently that would result
in that very slight (but consistent?) difference between those two
products?

If he has two machines or processes for creating the two products
(welding O2 and medical O2) and if the welding O2 product is more
"pure", then why would he operate two processes instead of simply using
a single process (the higher purity process) to create *both* of them?
Especially since the welding product is retailed at a lower price to
start with.

They aren't doing anything different, those are the *standards*, not the
actual product spec. The reality is that both grades (actually four
since there is an "aviator" grade and an "analytical" grade as well) are
filled from the same cryo tanks and both exceed the 99.99% welding grade
standard. Only the analytical grade gets extra attention to ensure it is
99.999% pure.

Steve B wrote:

"Ed Pawlowski" wrote in message
...

"Some Guy" wrote in message
...
Ed Pawlowski wrote:

Certification. Medical oxygen has to be certified to a certain
purity, welding does not.

How exactly can compressed oxygen be "impure" ?

Are some oxygen molecules more pure than other oxygen molecules?


The content of bottled oxygen is not 100% pure. It is 99.xxx% pure. That
other tiny amount can be anything in the atmosphere or it can be some
contaminant from the bottle. I used to work with medical oxygen and
every batch had a certification giving the purity.



Or does the Medical oxygen tank look nicer and cleaner than the Welding
oxygen tank?

You pay for that test and the potential liability that goes
along with it.

I think you pay more for medical and aviation O2 because the
consequences can be more expensive if there is a problem with the
product (the product being compressed oxygen).

That is what I just said above.


The product itself is no
more expensive or different or has any additional processing steps done
to it on the basis of it's sale in it's variously-labelled forms.

It has a step that does not have to be taken with welding oxygen.
Certification. O2 tanks have been contaminated in the past. Rare, but it
has happened. Filling my own tanks, I'd not be concerned about using
welding oxygen, but I'm not so quick to grab a tank off the back of a
truck at a job site and start breathing it. If you get the certification
with welding grade, then it is the same. That piece of paper is worth a
lot of money if there ever was a problem.

When I was a commercial deep sea diver, the oxygen we used in decompression
chambers was the same oxygen that we used for OA cutting. We did not use
medical oxygen.

I've seen this as well, just one big rack of "welding" O2 cylinders,
grab one for cutting, or grab one for the hyperbaric chamber, all the
same.

Doug Miller wrote:

In article ,
Steve Barker wrote:
On 6/18/2010 8:58 PM, Some Guy wrote:
Is there any difference between a tank of welding oxygen vs medical
oxygen as far as purity, concentration, hazardous impurities, etc, that
would render welding oxygen insufficient (or even dangerous) for helping
to supplement breathing / respiration ?

it's the same.

Ummm..... no, it's not. Read the other responses in this thread from people
who actually know the difference.

Yes, it's the same. Anything to the contrary is "urban legend" or hype
for the purpose of charging more for the same stuff. All the O2 grades,
including the five nines analytical grade are filled from the same cryo
tanks, and only the analytical grade gets any extra testing to ensure
the 99.999% spec. The reality is that the welding O2 purity standard
(99.99%) is higher than the medical O2 purity standard (99.95%), and
that the actual product from the gas suppliers exceeds those purity
standards by a wide margin.

Doug Miller wrote:

In article , Jim Yanik wrote:
(Doug Miller) wrote in
:

In article , Steve
Barker wrote:
On 6/19/2010 8:01 AM, Doug Miller wrote:
In articleSK2dnRfBjvQiJ4HRnZ2dnUVZ_oWdnZ2d@giganews. com,
Steve wrote:
On 6/18/2010 8:58 PM, Some Guy wrote:
Is there any difference between a tank of welding oxygen vs
medical oxygen as far as purity, concentration, hazardous
impurities, etc, that would render welding oxygen insufficient (or
even dangerous) for helping to supplement breathing / respiration
?

it's the same.

Ummm..... no, it's not. Read the other responses in this thread from
people who actually know the difference.

i read the responses. It's the same.

So the people who said it's not the same are wrong?


the people who said they're different said it a long time ago when they
actually were different.
Times have changed,they no longer actually are different.

Uh-huh. Right. Welding oxygen is certified just as pure as medical oxygen, no
contaminants. Suuuurrrrre it is. That's why they use welding oxygen in
hospitals.

As has been noted many times already, the welding grade purity standard
is higher than that for the medical grade. People who do not know
anything about welding think it's some low standards dirty process, but
that is simply not the reality. Impurities in O2 that are harmless for
human use, will cause welds to fail inspections.

Welding O2 standard 99.99% pure O2
Medical O2 standard 99.95% pure O2

The reality is that the actual product in the cylinders is closer to
99.999% pure, the analytical grade standard.

On Sun, 20 Jun 2010 10:45:20 -0500, Pete C. wrote:

AZ Nomad wrote:

On Sat, 19 Jun 2010 22:27:17 -0500, Pete C. wrote:

The purity standard for welding O2 is higher than the purity standard
for medical O2. In reality all three normal grades you can get, welding,
medical and aviator exceed all of the standards. Only the analytical
grade is higher purity.

Nope. Why don't you look it up, starting with 1) the percentage of oxygen
and ending with 2) the levels of impurities.

You can't use welding O2 for medical purposes but you can use medical O2
for welding.

Nope, exactly the opposite.

Your assertion is in direct opposition to purity standards especially
those regarding impurities.

Why don't you make a slight attempt to educate yourself?

AZ Nomad wrote:

On Sun, 20 Jun 2010 10:45:20 -0500, Pete C. wrote:

AZ Nomad wrote:

On Sat, 19 Jun 2010 22:27:17 -0500, Pete C. wrote:

The purity standard for welding O2 is higher than the purity standard
for medical O2. In reality all three normal grades you can get, welding,
medical and aviator exceed all of the standards. Only the analytical
grade is higher purity.

Nope. Why don't you look it up, starting with 1) the percentage of oxygen
and ending with 2) the levels of impurities.

You can't use welding O2 for medical purposes but you can use medical O2
for welding.

Nope, exactly the opposite.

Your assertion is in direct opposition to purity standards especially
those regarding impurities.

Why don't you make a slight attempt to educate yourself?

Why don't you do some research? I actually use O2 regularly, both for
welding / cutting as well as for breathing and nitrox blending. I'm well
aware of the fact that the welding O2 purity standard is tighter than
the standard for medical O2, as well as the fact that all grades of O2
from any of the large gas suppliers exceeds both the welding and medical
purity standards by a significant margin.

Ed Pawlowski wrote:

"Some Guy" wrote
Like I just said, the presence of impurities does not necessarily equate
to medical safety or have a health impact. If those impurities are
nitrogen or water vapor, then what exactly are the health implications
of those?

But if the analysis does not say what the impurities are, you are trading on
dangerous ground. That welding tank may have been used along with any
other gas used in industrial environments.


You can't use welding O2 for medical purposes

Says who?

A lawyer? Or a biochemist?

Lawyers and other sensible people that do not know what other gas may be in
there. Oxygen falls into the same type of situation ad drugs. The active
ingredients of a pill are often a small percentage of the tablet, the rest
being inert ingredients. There are regulations on what those inert
ingredients can be. There are regulations on how they are handled.

If I was dying in an emergency situation from lack of oxygen, I'd grab any
tank available. If I was at home with COPD, I'd want to be sure that tank
was handled in a proper manner and would not make me worse off.



You're stuck on old paranoia based on information that is decades out of
date. All of the O2 purity grades specify no more than 0.05% impurities,
and the most lax of the standards is the medical / aviator grade. The
reality is that all the grades are filled from the same cryo O2 source
and all are better than 99.99% pure O2.

On Sun, 20 Jun 2010 12:25:27 -0500, Pete C. wrote:

AZ Nomad wrote:

On Sun, 20 Jun 2010 10:45:20 -0500, Pete C. wrote:

AZ Nomad wrote:

On Sat, 19 Jun 2010 22:27:17 -0500, Pete C. wrote:

The purity standard for welding O2 is higher than the purity standard
for medical O2. In reality all three normal grades you can get, welding,
medical and aviator exceed all of the standards. Only the analytical
grade is higher purity.

Nope. Why don't you look it up, starting with 1) the percentage of oxygen
and ending with 2) the levels of impurities.

You can't use welding O2 for medical purposes but you can use medical O2
for welding.

Nope, exactly the opposite.

Your assertion is in direct opposition to purity standards especially
those regarding impurities.

Why don't you make a slight attempt to educate yourself?

Why don't you do some research? I actually use O2 regularly, both for
welding / cutting as well as for breathing and nitrox blending. I'm well
aware of the fact that the welding O2 purity standard is tighter than
the standard for medical O2, as well as the fact that all grades of O2
from any of the large gas suppliers exceeds both the welding and medical
purity standards by a significant margin.

It isn't. Read on impurities, not just the main percentage of O2.

On Sun, 20 Jun 2010 12:28:09 -0500, Pete C. wrote:

Ed Pawlowski wrote:

"Some Guy" wrote
Like I just said, the presence of impurities does not necessarily equate
to medical safety or have a health impact. If those impurities are
nitrogen or water vapor, then what exactly are the health implications
of those?

But if the analysis does not say what the impurities are, you are trading on
dangerous ground. That welding tank may have been used along with any
other gas used in industrial environments.


You can't use welding O2 for medical purposes

Says who?

A lawyer? Or a biochemist?

Lawyers and other sensible people that do not know what other gas may be in
there. Oxygen falls into the same type of situation ad drugs. The active
ingredients of a pill are often a small percentage of the tablet, the rest
being inert ingredients. There are regulations on what those inert
ingredients can be. There are regulations on how they are handled.

If I was dying in an emergency situation from lack of oxygen, I'd grab any
tank available. If I was at home with COPD, I'd want to be sure that tank
was handled in a proper manner and would not make me worse off.



You're stuck on old paranoia based on information that is decades out of
date. All of the O2 purity grades specify no more than 0.05% impurities,
and the most lax of the standards is the medical / aviator grade. The
reality is that all the grades are filled from the same cryo O2 source
and all are better than 99.99% pure O2.

Again, you ignore impurities and only look at the O2 percentage.

AZ Nomad wrote:

On Sun, 20 Jun 2010 12:28:09 -0500, Pete C. wrote:

Ed Pawlowski wrote:

"Some Guy" wrote
Like I just said, the presence of impurities does not necessarily equate
to medical safety or have a health impact. If those impurities are
nitrogen or water vapor, then what exactly are the health implications
of those?

But if the analysis does not say what the impurities are, you are trading on
dangerous ground. That welding tank may have been used along with any
other gas used in industrial environments.


You can't use welding O2 for medical purposes

Says who?

A lawyer? Or a biochemist?

Lawyers and other sensible people that do not know what other gas may be in
there. Oxygen falls into the same type of situation ad drugs. The active
ingredients of a pill are often a small percentage of the tablet, the rest
being inert ingredients. There are regulations on what those inert
ingredients can be. There are regulations on how they are handled.

If I was dying in an emergency situation from lack of oxygen, I'd grab any
tank available. If I was at home with COPD, I'd want to be sure that tank
was handled in a proper manner and would not make me worse off.



You're stuck on old paranoia based on information that is decades out of
date. All of the O2 purity grades specify no more than 0.05% impurities,
and the most lax of the standards is the medical / aviator grade. The
reality is that all the grades are filled from the same cryo O2 source
and all are better than 99.99% pure O2.

Again, you ignore impurities and only look at the O2 percentage.

So provide a cite to your claimed impurity information, and what
impurity present at 0.001% concentration in the O2 is such a hazard.

On 6/20/2010 10:38 AM, Ed Pawlowski wrote:

"The Daring Dufas" wrote

It wouldn't surprise me if the LOX tank is used to fill portable tanks
for patient use. I'll have to ask one of my friends who works
maintenance at the hospital.

TDD

LOX tanks fill LOX tanks. They can be filled for patient use of that is
what their supplier gives them. They are a different setup that using
compressed O2 though. Different tanks, regulators, etc. They are not
usually filled at hospital though, but by independent providers.

Compressed tanks either need mechanical pumps or, most home medical
suppliers use a cascade system of tanks increasing pressure into the
smaller tanks with each on up the line.

Hummmm, so you say LOX can't be allowed to boil off into O2 gas and
be distributed all over a hospital campus or used to fill portable
O2 tanks? UAB hospital has several hospitals next door. The VA, the
county hospital, The Eye Foundation and several clinics are all on
the same street. Many are connected by skywalks so I have to believe
they share resources.

TDD

On Jun 20, 8:47*am, "Ed Pawlowski" wrote:
"Some Guy" wrote

Like I just said, the presence of impurities does not necessarily equate
to medical safety or have a health impact. *If those impurities are
nitrogen or water vapor, then what exactly are the health implications
of those?

But if the analysis does not say what the impurities are, you are trading on
dangerous ground. * That welding tank may have been used along with any
other gas used in industrial environments.



You can't use welding O2 for medical purposes

Says who?

A lawyer? *Or a biochemist?

Lawyers and other sensible people that do not know what other gas may be in
there. *Oxygen falls into the same type of situation ad drugs. *The active
ingredients of a pill are often a small percentage of the tablet, the rest
being inert ingredients. *There are regulations on what those inert
ingredients can be. *There are regulations on how they are handled.

If I was dying in an emergency situation from lack of oxygen, I'd grab any
tank available. If I was at home with COPD, I'd want to be sure that tank
was handled in a proper manner and would not make me worse off.

exactly as I was taught in First Aid. Any tank of oxy (be sure it is
oxy and not just compressed air) will do in an emergency but use
medical for extended periods.

Harry K

"The Daring Dufas" wrote
Compressed tanks either need mechanical pumps or, most home medical
suppliers use a cascade system of tanks increasing pressure into the
smaller tanks with each on up the line.

Hummmm, so you say LOX can't be allowed to boil off into O2 gas and
be distributed all over a hospital campus or used to fill portable
O2 tanks?


No, not what I said, It is done often for use, but not for filling tanks.
What I did was is that the oxygen coming off of the LOX is not of sufficient
pressure to fill a compressed tank, you need mechanical pumps to assist.
There are small tanks that can be filled with LOX from big tanks and that is
allowed for local use or portables. You are confusing two different forms
of O2 and the equipment used for them.


UAB hospital has several hospitals next door. The VA, the
county hospital, The Eye Foundation and several clinics are all on
the same street. Many are connected by skywalks so I have to believe
they share resources.

I doubt they have a central tank to go that distance, but I've not seen it.
Post photos or drawings of the layout when you get them.

On 6/20/2010 3:47 PM, Ed Pawlowski wrote:

"The Daring Dufas" wrote
Compressed tanks either need mechanical pumps or, most home medical
suppliers use a cascade system of tanks increasing pressure into the
smaller tanks with each on up the line.

Hummmm, so you say LOX can't be allowed to boil off into O2 gas and
be distributed all over a hospital campus or used to fill portable
O2 tanks?


No, not what I said, It is done often for use, but not for filling
tanks. What I did was is that the oxygen coming off of the LOX is not of
sufficient pressure to fill a compressed tank, you need mechanical pumps
to assist. There are small tanks that can be filled with LOX from big
tanks and that is allowed for local use or portables. You are confusing
two different forms of O2 and the equipment used for them.


UAB hospital has several hospitals next door. The VA, the
county hospital, The Eye Foundation and several clinics are all on
the same street. Many are connected by skywalks so I have to believe
they share resources.

I doubt they have a central tank to go that distance, but I've not seen
it. Post photos or drawings of the layout when you get them.

I'll see what I can find out from some of the guys who work there. If
I take pictures, the UAB police may tackle me as a terrorism suspect.
I may drive by with my camera this week.

TDD

Ed Pawlowski wrote:

O2 tanks used by hospitals are more likely to be part of a
manifold system, and as such will always be maintained at
some positive pressure by virtue of the fact that at least
one of their "gang-mates" is likely to have enough excess
pressure to keep them partially pressurized.

You think wrong. Medical oxygen is used in many places aside from
hospitals. Thousands of bottle every day are used in private
homes.

Even the large tanks (5-foot tall) are used in homes?

They are single size, no manifolds, They are generally used
until empty. Valves are left open, regulators removed.
They are sometimes stored in poor environments, must basements,
trunk of a car, under the sink, laundry room.

So what you're saying is that welding tanks are probably safer - because
they're not as exposed to such nasty conditions and situations as the
home-use medical tanks are? And welding tanks are more likely to be
returned with some positive pressure - as opposed to home-use medical
tanks as you have just described?

And so far, it's just been pure speculation here that tanks
of welding O2 are *not* evacuated prior to filling, just as
supposedly medical tanks are.

Not speculation. I've filled tanks. I followed the regulations.

So go further and tell us if welding tanks are, or are not, evacuated
prior to being refilled.

"Pete C." wrote:

What is the compressed gas supplier doing differently that would
result in that very slight (but consistent?) difference between
those two products?

They aren't doing anything different, those are the *standards*,
not the actual product spec. The reality is that both grades are
filled from the same cryo tanks and both exceed the 99.99% welding
grade standard.

So how is it known that these gasses meet this 99.99% spec?

Are they tested?

Or are they compressed with equipment that is known to NOT inject
contaminents during pressurization?

Much of what is speculated here is not with the "purity" of the source
gas, or the compentency of the compression equipment to maintain that
purity as a tank is being pressurized, but with what *might* happen with
these tanks when in the hands of end-users as they reach their empty
state prior to being returned to be reused.

Seems that some people here are hung up on that point, and we are all
speculating as to just what the gas retailer does behind the scenes with
these returned tanks prior to refilling them.

"Some Guy" wrote in message ...
Ed Pawlowski wrote:


You think wrong. Medical oxygen is used in many places aside from
hospitals. Thousands of bottle every day are used in private
homes.

Even the large tanks (5-foot tall) are used in homes?

Yes. sometimes. That is an "H" tank. Most home uses is smaller "D" tanks.
D and E tanks are generally used as portables or for emergency backup if a
concentrator fails or if there is a power failure.


So what you're saying is that welding tanks are probably safer - because
they're not as exposed to such nasty conditions and situations as the
home-use medical tanks are? And welding tanks are more likely to be
returned with some positive pressure - as opposed to home-use medical
tanks as you have just described?

Show me where I said industrial tanks are not exposed to nasty conditions.


And so far, it's just been pure speculation here that tanks
of welding O2 are *not* evacuated prior to filling, just as
supposedly medical tanks are.

Not speculation. I've filled tanks. I followed the regulations.

So go further and tell us if welding tanks are, or are not, evacuated
prior to being refilled.

I worked with medical, not industrial so I don't know the answer, nor do I
care. Medical oxygen comes with paperwork. That makes it different and the
only way it can be used for a patient. Think what you want, but unless it
is medical grade, no oxygen supplier is going to give a tank to a patient.

"Pete C." wrote

You're stuck on old paranoia based on information that is decades out of
date. All of the O2 purity grades specify no more than 0.05% impurities,
and the most lax of the standards is the medical / aviator grade. The
reality is that all the grades are filled from the same cryo O2 source
and all are better than 99.99% pure O2.

I know how a medical tank was handled. I don't know anything abut a welding
tank. The oxygen may be pure going in, but I don't know what was in the
tank beforehand.

I'm not stuck on decades information, my son owns a medical supply company
that supplies oxygen. I worked part time for him filling tanks and
delivering LOX. We followed the regulations on medical oxygen. You are
free to breath whatever you like though.

On 6/21/2010 4:47 AM, Ed Pawlowski wrote:

"Some Guy" wrote in message
...
Ed Pawlowski wrote:


You think wrong. Medical oxygen is used in many places aside from
hospitals. Thousands of bottle every day are used in private
homes.

Even the large tanks (5-foot tall) are used in homes?

Yes. sometimes. That is an "H" tank. Most home uses is smaller "D"
tanks. D and E tanks are generally used as portables or for emergency
backup if a concentrator fails or if there is a power failure.


So what you're saying is that welding tanks are probably safer - because
they're not as exposed to such nasty conditions and situations as the
home-use medical tanks are? And welding tanks are more likely to be
returned with some positive pressure - as opposed to home-use medical
tanks as you have just described?

Show me where I said industrial tanks are not exposed to nasty conditions.


And so far, it's just been pure speculation here that tanks
of welding O2 are *not* evacuated prior to filling, just as
supposedly medical tanks are.

Not speculation. I've filled tanks. I followed the regulations.

So go further and tell us if welding tanks are, or are not, evacuated
prior to being refilled.

I worked with medical, not industrial so I don't know the answer, nor do
I care. Medical oxygen comes with paperwork. That makes it different and
the only way it can be used for a patient. Think what you want, but
unless it is medical grade, no oxygen supplier is going to give a tank
to a patient.


A fellow I know works on X-ray equipment and said the 50 cent bolt from
HD or Lowe's costs $25 if it's for one of his X-ray machines. The reason
being a stack of paperwork required for each little part. Is it
an exaggeration? I don't know but I know someone who does and I may have
to drop by and ask him.

TDD