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pgmrdan
10-12-2011, 03:04 PM
I'm reading through a welding book last night and the author states that pure oxygen is flammable.

What say you?

moe1942
10-12-2011, 03:23 PM
O2 by itself no, but combustion without it is not possible. The more O2 the more violent the fire..Oxy/acetylene cutting is a good illustration of this.

ironnut
10-12-2011, 03:34 PM
Okay, I will bite. Oxygen is not flammable. It is an oxidizer and not a fuel. It is highly reactive and supports combustion. There are a large number of oxides that form when a wide variety of materials, elements react with it. Iron easily burns in the presence of pure oxygen so iron is a fuel and it is flammable in the presence of oxygen.

gordon

PTSideshow
10-12-2011, 03:56 PM
You you should state the authors name so others can avoid wasting money on the book his initials wouldn't be R.F. would they.

Evan
10-12-2011, 04:28 PM
No pure element is flammable by itself. It requires at least two elements to make a chemical compound via an exothermic reaction.

Willy
10-12-2011, 04:30 PM
I'd say it's time to get a new book.:D

Are you still reading that same book?
Not trying to be be negative, but did the answers not sit right with you the last time you asked this question?
http://bbs.homeshopmachinist.net/showthread.php?t=14706

Like I said, I'm not here to jump on anybody, just wondered what I'm missing.:)

goose
10-12-2011, 04:52 PM
I say it is flammable.

O2, the presence of which supports combustion. The fact that it is considered an oxidizer rather than a fuel in a chemical reaction is semantics.

A leaking O2 cylinder can turn a lit cigarette into a conflagration. Just as much as a leaking acetylene cylinder.

It is flammable in the sense it is not non-flammable, as could describe asbestos. But O2 can be described as flammable, reactive, explosive, corrosive, etc.

pgmrdan
10-12-2011, 04:58 PM
Thanks Willy!!!

I thought I might have posted that here before but I didn't look long enough to find it. Geez, that was over 5 years ago. At least I'm consistent. :D

Yep, I read parts of that book before but never finished it so I began again.

That still burns my butt that he put that in his book.

He wrote some more stuff in there that I question too but so far that's the one that bugs me the most.

Peter.
10-12-2011, 05:09 PM
It's not flammable but in concentrations higher than what you find naturally it can turn stuff that would not normally burn into flammable material. An oxy-acetylene torch is one example - the jet of pure oxygen when pressing the lever causes the iron or steel to ignite.

rohart
10-12-2011, 05:11 PM
There are many reactions where a material combines with a gas other than oxygen to produce heat to the extent that the gaseous and particulate products glow. Whether you call this burning, and whether you say that X is flammable in Y, is up to you.

Either way, it's the material that's flammable in the gas. The gas is not the flammable substance. The gas supports combustion.

If you create conditions so artificial that you ignite a jet of oxygen in an atmosphere of methane, say, then bully for you, and maybe then the oxygen is burning.

Under normal conditions, oxygen is not flammable.

ptjw7uk
10-12-2011, 05:17 PM
Burning is oxidation so what does oxygen oxidise to?

Peter

Forrest Addy
10-12-2011, 05:22 PM
You guys got it all wrong. It toke phlogiston to keep a fire going. Spark plugs are phlogiston injectors etc. Then there is captive phligiston like in the bvatteries of flashlights. It's all very scienfific

Buncha morons. Have to explain everything to them.

Lew Hartswick
10-12-2011, 06:34 PM
Some of the answers to questions like this are what almost convince me to stop reading bulletin boards. The folks that insist on re-defining a word to suit their biases or erroneous ideas. If everyone was free to change the meaning of a word just imagine how much information would ever get transferred. About ZERO. :-(
...lew...

Forestgnome
10-12-2011, 06:59 PM
Flammability is a measure of how easliy a product can be ignited to start burning. Burning is a process of oxidation. Oxygen cannot be oxidized, therefore is not flammable. Most everything else is flammable in the presence of pure oxygen, even diamond.

rp designs
10-12-2011, 07:09 PM
O2 + Heat --->O2

Not flammable. Oxygen supports combustion but by itself it is not combustible. However real world is that everything around us is fairly combustible and if you add oxygen it is only going to make it more so.

Iraiam
10-12-2011, 07:15 PM
Oxygen is not flammable, however, a high concentration of oxygen makes most things much more flammable, even explosive.

A perfect example is a guy I used to work with, his mother was on oxygen 24 hours a day for health reasons, she smoked cigarettes, one day something happened in her home while she was smoking, likely on oxygen at the same time. The oxygen rich environment led to the house burning down literally in just minutes.

goose
10-12-2011, 07:21 PM
O2 + Heat --->O2

Not flammable.


CH4 (methane) + heat = CH4

Not flammable

Oxygen is part of combustion, producing flame, hence is flammable.

We live on a planet with 20 percent O2 atmosphere. That default seems to provide confusion, I suppose if I lit a cigarette on a planet with a methane atmosphere it would be more likely to burst into flame?


Just my opinion,

Evan
10-12-2011, 07:53 PM
CH4 (methane) + heat = CH4

Not so. CH4 is a compound, not an element and if sufficient heat is provided it will decompose to hydrogen and carbon.

The word "flammable" is scientifically ambiguous. It doesn't have a defined meaning with implied or explicit parameters. Even the word "oxidize" or "oxidizer" is not always taken to mean a reaction that includes oxygen. The word "exothermic" is scientifically specific in that it means any reaction that releases heat.

For the sake of precision of meaning it is necessary to agree on a definition of the word "flammable". I take it to mean a substance that can be induced to produce an exothermic reaction.

Note that the word "substance" is also ambiguous. I define it as a quantity of matter without specific properties or implied composition . It may be a single element or any possible combination of elements individually or as compounds.

Given those definitions then single elements are not flammable under any conditions but combinations of elements or compounds may be flammable.

philbur
10-12-2011, 07:57 PM
Priceless.:rolleyes:

Phil:)


CH4 (methane) + heat = CH4

Not flammable

Oxygen is part of combustion, producing flame, hence is flammable.

We live on a planet with 20 percent O2 atmosphere. That default seems to provide confusion, I suppose if I lit a cigarette on a planet with a methane atmosphere it would be more likely to burst into flame?


Just my opinion,

wierdscience
10-12-2011, 08:06 PM
An oxy-acetylene torch is one example - the jet of pure oxygen when pressing the lever causes the iron or steel to ignite.

Actually it causes it to oxidize,not ignite or combust.This is why Stainless Steel won't cut with an OA torch unless flux injection is used to stop chromium oxide from forming on the surface which stops the reaction.

http://www.welding-technology-machines.info/thermal-cutting-of-metals/chemistry-of-flame-cutting.htm

Duffy
10-12-2011, 08:17 PM
Sorry guys, but oxygen IS flammable in ONE particular circumstance. Specifically, oxygen will "burn" in an atmosphere of FLOURINE gas. The reaction product is flourine monoxide. We are not going to run into this situation very often but, should the circumstances arise, oxgen WILL burn.

Evan
10-12-2011, 09:46 PM
Invoking Fluorine is almost unfair. Fluorine will react with almost anything, even including the "inert" gas xenon to form xenon tetrafluoride. ;)

goose
10-12-2011, 09:49 PM
Not so. CH4 is a compound, not an element and if sufficient heat is provided it will decompose to hydrogen and carbon.

While technically true, you bring it to an extreme , following that logic, so too would O2 undergo molecular disintegration if enough heat where applied. If enough heat were applied, then any element would eventually undergo fusion and turn into a different substance.




For the sake of precision of meaning it is necessary to agree on a definition of the word "flammable". I take it to mean a substance that can be induced to produce an exothermic reaction.



Disagree. an exothermic reaction does not necessarily produce flame. Take for instance plaster of paris, mixed with water an exothermic reaction takes place and the substance heats up, but no flame produced.

I think flammable means any substance (oxidizer or fuel) which can sustain a combustive reaction. That reaction typically, but not exclusively, takes place in the open air.

Evan
10-12-2011, 10:56 PM
While technically true, you bring it to an extreme , following that logic, so too would O2 undergo molecular disintegration if enough heat where applied. If enough heat were applied, then any element would eventually undergo fusion and turn into a different substance.

Firstly, fusion isn't a chemical reaction. Second, simply heating oxygen will not cause it to fuse. It must also be maintained at or above a minimum density. That is not just a matter of putting it in a pressure vessel. Maintaining that minimum density requires a containment other than matter.

Also, O1 and O2 are still the same element.


I think flammable means any substance (oxidizer or fuel) which can sustain a combustive reaction.


"Flammable" comes from the Latin Flamma which means flame. It doesn't exclude reactions that do not involve oxygen since it doesn't require oxygen to produce a flame. The term combustion comes from the Latin combustus which means "burnt". However, the original meaning isn't exclusive to exothermic oxygen reactions that produce a flame. It simply means the appearance of being or having been (combusted) subjected to heat regardless of the source.

Also, the setting of plaster of paris is scientifically a form of combustion.



com·bus·tion 
 [kuhm-buhs-chuhn]
noun
1. the act or process of burning.

2. Chemistry .
a. rapid oxidation accompanied by heat and, usually, light.
b. chemical combination attended by production of heat and light.
c. slow oxidation not accompanied by high temperature and light.

http://dictionary.reference.com/browse/combustion


Note also the the term "oxidation" is properly replaced by the term "redox reaction" which includes chemical reactions other than those involving oxygen.

boslab
10-13-2011, 01:22 AM
Invoking Fluorine is almost unfair. Fluorine will react with almost anything, even including the "inert" gas xenon to form xenon tetrafluoride. ;)
+1, for that!, i know lets heat some steel for forging by burning diamonds or somthing! lol, the flourine combines with the oxygen tis true but does that make the oxygen 'burn' or redox or whatever, i'd say no myself and that oxygen is not flammable ITSELF, but its handy stuff in bottles!
mark

mike os
10-13-2011, 02:21 AM
dont you boys have anything better to do?

:rolleyes:

Jaakko Fagerlund
10-13-2011, 03:58 AM
I think flammable means any substance (oxidizer or fuel) which can sustain a combustive reaction.
Think what you like, but it doesn't hold truth at all. I can think that a tractor is actually a pencil, but it still isn't a pencil.

Evan
10-13-2011, 07:00 AM
Heh. [stirs pot] Technically, water is an ash...

philbur
10-13-2011, 07:03 AM
Obviously not, 27 posts and mostly drivel. Well 26 actually cause I made one good post, oh and of course yours is not drivel, that goes without saying. :cool:

Why the hell can't we have a really sensible thread like: "worn out old American crap" versus "Shiny new rubbish from China" :D

Phil:)


dontyo boys have anything better to do? :rolleyes:

aboard_epsilon
10-13-2011, 07:35 AM
here's one for you

if oxygen was fed through a wick like kerosene and set fire to... would it burn like kero..or would it consume the wick quickly.

all the best.markj

Forestgnome
10-13-2011, 07:54 AM
Since flammability isn't a scientific term used in chemistry and physics, for the purpose of this argument you must fall back on either common usage or the definition from the classifying entity. The classifying entity in this case would likely be the National Fire Protection Agency. Their classifications are based on the ability of a substance to be ignited in air. Although there will be die-hards that contend there is the possibilty of ignition in an air/oxygen mix, you'ld be hard pressed to find experimental evidence of such an occurence.

goose
10-13-2011, 08:32 AM
Firstly, fusion isn't a chemical reaction. Second, simply heating oxygen will not cause it to fuse.


You're hiding behind weak semantics and obfuscating the issue. You were using hyperbole by first bringing up molecular disintegration and I returned the hyperbole in spades.




Flamma = flame

Flammable = flame producing.

O2 can produce, sustain, cause and accelerate flame.

Therefore is flammable.



The op wasn't reading out of a chemistry textbook, but a welding book. The caution of O2 being flammable may not suit some individuals' particularities for technically accuracy, but the caution is still valid.

The reactivity of O2, especially in concentrated form, makes it indeed more dangerous and potentially more flammable than many substances (fuels) otherwise thought of as highly flammable. Oily rags would be more likely to spontaneously combust in an oxygen rich environment.



No doubt when the Apollo 1 astronauts burst into flame it wasn't the oxygen rich space capsule that was at fault, it was their darn bodies that were so darn flammable.

Lew Hartswick
10-13-2011, 08:50 AM
I think there are about to be some additions to my "ignore list". :-)
...lew...

A.K. Boomer
10-13-2011, 09:08 AM
here's one for you

if oxygen was fed through a wick like kerosene and set fire to... would it burn like kero..or would it consume the wick quickly.

all the best.markj


uhhhhm - quickly --- as in like "explosively quickly"


someone mentioned that oxygen is not combustible but combustion is not possible without it --- isn't there some anaerobic compounds that don't require oxygen to "go off" --- maybe we need to re-define the word "combustion" ???

jcsites
10-13-2011, 09:14 AM
I agree with you and that's a real fact. Don't just believe on what you read in a certain book...

gary350
10-13-2011, 10:20 AM
Pure 02 by itself is not flammable.

madwilliamflint
10-13-2011, 10:39 AM
This is really a 4 page argument?

Oxygen is not flammable. It does not oxidize. The process of oxidation requires fuel that is not oxygen.

pgmrdan
10-13-2011, 10:56 AM
I was simply looking for 'yes' or 'no'. Why didn't I find my previous post so I wouldn't have asked again? Why, oh why??? :(

Actually, like just about everything I read here, I find this very interesting. The interesting part is not necessarily the answers to my question but the way people here interact. :D

Evan
10-13-2011, 12:40 PM
You're hiding behind weak semantics and obfuscating the issue. You were using hyperbole by first bringing up molecular disintegration and I returned the hyperbole in spades.

Molecular dissociation and atomic dissociation are the difference between a firecracker and an atomic bomb. One involves electromagnetic molecular binding forces and the other involves the atomic weak and strong force. It is hardly "hyperbole" or a matter of semantics.

Molecular dissociation is how combustion works. Atomic dissociation and fusion have absolutely nothing to do with combustion.

moe1942
10-13-2011, 12:43 PM
And at the risk of repeating myself the answer is no to the op's question...

Forrest summed it up..

Evan
10-13-2011, 12:48 PM
No doubt when the Apollo 1 astronauts burst into flame it wasn't the oxygen rich space capsule that was at fault, it was their darn bodies that were so darn flammable.

No, it was the materials used in the construction of the capsule that were "so darn flammable". Humans can breath pure oxygen just fine.

A.K. Boomer
10-13-2011, 01:18 PM
. Humans can breath pure oxygen just fine.



nope.......

goose
10-13-2011, 01:38 PM
No, it was the materials used in the construction of the capsule that were "so darn flammable". Humans can breath pure oxygen just fine.


The materials in the capsule were not particularly flammable, except in the presence of a pure O2 atmosphere, which was the case. A factor apparently ignored or poo-pooed by NASA engineers. Probably the same mentality that says O2 is not-flammable. An exercise in semantics. As if the direction in which electrons move in a chemical reaction is relevant to the final result (fire)

If a mundane substance, - fabric, or paper or whatever becomes saturated with O2 molecules from being in a Oxygen rich environment, and then a flash fire results, what's the primary issue causing increased flammabilty?

By saying O2 is non-flammable you're implying it's safe near open spark or flame, as though it's the same as CO2.

Imagine this conversation I'll have with my son 12 years from now:

Son: Hey Dad, can I smoke weed while I'm playing around with this Oxygen cylinder in your shop?

Me: Sure son, no problem, we all know Oxygen is non-flammable.

flathead4
10-13-2011, 02:15 PM
I would bet that the term "flammable"; meaning liable to catch fire or readily combustible, was in use before it was known that O2 was required. Since then and for anyone with a high school education, flammable would mean "readily combustible when combined with O2 in proper concentration." It's common knowledge that gasoline (considered flammable) in a container that is free of O2 will not burst into flames any more that a tank of pure O2 will burst into flames. We all know that the the two must be combined before combustion can occur. As stated before, flammable is a layman's term and the OP's question is basically bogus.

Tom

flathead4
10-13-2011, 02:20 PM
Me: Sure son, no problem, we all know Oxygen is non-flammable.


Or you could teach him about combustion. If you don't know how it works, there are plenty of resourses on line or at your library.

Tom

derekm
10-13-2011, 02:30 PM
...
If you create conditions so artificial that you ignite a jet of oxygen in an atmosphere of methane, say, then bully for you, and maybe then the oxygen is burning.

...
The first demonstration by my physics teacher in grammar school was exactly this.
:D

flathead4
10-13-2011, 03:22 PM
The more O2 the more violent the fire..Oxy/acetylene cutting is a good illustration of this.


But only within the flammabilty limit of the material.

Tom

Jaakko Fagerlund
10-13-2011, 03:37 PM
If a mundane substance, - fabric, or paper or whatever becomes saturated with O2 molecules from being in a Oxygen rich environment, and then a flash fire results, what's the primary issue causing increased flammabilty?
Nobody isn't denying that oxygen increases flammability of flammable materials, but you are just too thick to understand that oxygen is not flammable. In your own example the fabric/paper/whatever is flammable.

Your son smoking weed would be the one flammable, don't blame oxygen if you don't understand simple things.

pgmrdan
10-13-2011, 03:50 PM
The materials in the capsule were not particularly flammable, except in the presence of a pure O2 atmosphere, which was the case. A factor apparently ignored or poo-pooed by NASA engineers. Probably the same mentality that says O2 is not-flammable. An exercise in semantics. As if the direction in which electrons move in a chemical reaction is relevant to the final result (fire)

If a mundane substance, - fabric, or paper or whatever becomes saturated with O2 molecules from being in a Oxygen rich environment, and then a flash fire results, what's the primary issue causing increased flammabilty?

By saying O2 is non-flammable you're implying it's safe near open spark or flame, as though it's the same as CO2.

Imagine this conversation I'll have with my son 12 years from now:

Son: Hey Dad, can I smoke weed while I'm playing around with this Oxygen cylinder in your shop?

Me: Sure son, no problem, we all know Oxygen is non-flammable.

That's a really, really bad example. The cigarette is flammable and in pure oxygen it will burn about 8 times as fast as in regular air. It will burn with a flame.

The cigarette burns, not the oxygen.

boslab
10-13-2011, 04:10 PM
i'm not about to argue but i have to wear a gas monitor, o2 is one of the things i have been told is nasty, it will in fact kill according to the health and safety executive, i have no reason to doubt them, pure 02 can be used in special circumstances, CO poisoning for example, hyperbaric oxy treatment for diseases like necrotising fasciutis [spelling?] are thy right or is it safe for me to breathe 99.99 02?
why does my monitor alarm over 22% 02?, i know it pools up in passages in work, the basic oxy plant stuffs 70.000m3 of oxy down the lances so leaks are inevitable.
what you think?
mark

pgmrdan
10-13-2011, 04:22 PM
Actually, nature is a rather hostile environment. Oxygen is a destructive gas that, even though we require it, we're able to tolerate fairly well.

We may be able to breathe pure oxygen for a while but for several reasons it's good that we don't have an atmosphere with a higher concentration of it.

Breathing pure oxygen can cause blindness in premature babies.

Can you imagine a brush fire in an atmosphere of pure oxygen?

Of course, an atmosphere of pure oxygen wouldn't remain pure oxygen for very long at all.

Duct Taper
10-13-2011, 04:25 PM
You guys got it all wrong. It toke phlogiston to keep a fire going. Spark plugs are phlogiston injectors etc. Then there is captive phligiston like in the bvatteries of flashlights. It's all very scienfific

Buncha morons. Have to explain everything to them.

That is why I keep at least 3 lb of anti-phlogiston around the shop. I haven't had a violent fire since I started that practice.

Most people don't realize that there is a lot of phlogiston in grease. Just put your oxy torch on just oxygen and point it at a gob of grease to see what happens. And keep the anti-phlogiston handy.

goose
10-13-2011, 04:44 PM
but you are just too thick to understand that oxygen is not flammable.

Ah yes, name calling, the hallmark of scientific peer review.:D

Apparently two avenues of thought are colliding in this thread;

1: Chemistry. The issue in the gaining of electrons during an exothermic reaction. You have already been proven wrong, in that even an oxidizer such as O2 can be "out-oxidized" by another element, flourine.

2: Pragmatically, (putting aside which way the electrons move), the issue of a descriptive word to assign to pure O2 stored in a cylinder or similar. Oxidizer, strong oxidizer, do not smoke, flammable, combustible, explosive, dangerous, flammable gas, etc. All these are acceptable, in my opinion. They convey the danger, they convey what not to do around the substance, but I think the best one, the one most recognizable and understandable to industry and the general public alike, is flammable.

pgmrdan
10-13-2011, 04:51 PM
I've never seen a 'flammable' sticker on a bottle of oxygen.

Evan
10-13-2011, 05:34 PM
I've never seen a 'flammable' sticker on a bottle of oxygen.

Exactly. That is because it isn't. It is an oxidizer of course which is how it is labeled.

Pure oxygen is not harmful at all as long as the partial pressure doesn't much exceed what we normally breath. The oxygen pressure at sea level is about 3 psi. It can be as low as about 2.5 psi and as high as 5 psi with no harm even over a long period. Astronauts always breath pure oxygen on EVA for as long as 8 or more hours at the same partial pressure found at sea level. The other gasses in our atmosphere, primarily nitrogen and argon with a small amount of CO2 are not required.

Breathing oxygen at 14.5 psi is harmful but that doesn't represent our atmosphere.

Evan
10-13-2011, 05:43 PM
You have already been proven wrong, in that even an oxidizer such as O2 can be "out-oxidized" by another element, flourine.

??

I said nothing that is proven wrong by that fact.

goose
10-13-2011, 05:45 PM
I've never seen a 'flammable' sticker on a bottle of oxygen.


http://www.hammerscale.com/images-global/o22.jpg




The defense rests.

garagemark
10-13-2011, 05:49 PM
Jeeze, this thread is STILL going?

You know what they (who the hell is they anyway?) say? Everything in moderation. Too much O2, you die. Too much methane? You die. Too much nitrogen (which you really need the most of), you die. Too much argument? You die of boredom.

Next page please.

firbikrhd1
10-13-2011, 06:33 PM
I've been following this thread for the past couple of days with a smile on my face. It's quite amusing to see the number of people who believe Oxygen is flammable, particularly with the Internet available for research.

During my career as a Firefighter (29 years) we learned much about Oxygen as it relates to EMS, Firefighting, Confined Space & Trench Rescue and Hazardous Materials calls. I am certified in all fields with the exception of Haz Mat, in which I have still had innumerable hours of training and experience. With regard to all disciplines mentioned with the exception of EMS, our main concern was for Oxygen enrichment although Oxygen deficiency also concerned us because that meant some other gas was taking it's place. During my career I received a tremendous amount of training and retraining in in each discipline and ran many calls of each type. Never once did anyone ever classify Oxygen to be flammable nor were we ever taught that. Oxygen is an oxidizer, it accelerates combustion. It can cause things that wouldn't ordinarily burn in our "normal" atmosphere, with about 21% Oxygen, to burn vigorously at increased percentages. A Slice Torch, for instance, uses hollow rolled steel rods and pure oxygen to burn the steel rod at extremely high temperatures for cutting all sorts of materials. The melting temperature of steel is around 2500 degrees F yet when oxygen is sent through the rolled steel rod used in a Slice Torch it can be ignited with a welder's striker, sparks with a much lower than 2500 degree temperature. In fact, an experienced welder can start cutting with a cutting torch, shut off the acetylene and continue the cut with pure oxygen given the right circumstances. In each case it is the steel burning, not the Oxygen.

Oxygen is used under pressure in a Hyperbaric Chamber to treat a number of maladies. Decompression chambers use 100% oxygen at 2.8 Bar to treat decompression sickness giving breaks at 20 minute intervals to prevent Oxygen toxicity. The only warning with regard to EMS we ever received was when treating infants or those with emphysema. Oxygen is considered to be a drug in Medical settings and we were taught that oxygen at 100% could cause blindness in infants. For patients with COPD (emphysema) Oxygen could also be problematic because their breathing drive was based on Oxygen and not Carbon Dioxide as is the norm for those without disease. Even so, the rule of thumb was never withhold Oxygen. If a COPD patient stopped breathing we simply did it for them via BVM (AMBU Bag) and Oxygen was administered via a blow by method for infants.

gaston
10-13-2011, 07:50 PM
Boy I think the winter doldroms are upon us! ok guys put down the keyboard and mouse and retreat to the shop. There must be something in there that needs cleaned, built or fixed. If not come on over and you can clean and sand on my latest project (a 210x1500 voest lathe)

mike4
10-13-2011, 07:59 PM
Boy I think the winter doldroms are upon us! ok guys put down the keyboard and mouse and retreat to the shop. There must be something in there that needs cleaned, built or fixed. If not come on over and you can clean and sand on my latest project (a 210x1500 voest lathe)
I second that , the posts all seem to indicate that some are sitting in the warm computer room and not working in the cold shop .
Oxygen in cylinders needs to be treated with respect and care ,something all seem to agree on .
The main thing is to not have it and fuels in close proximity unless it is for heating and cutting under controlled conditions .
The arguement and nit picking can be dragged on forever by people who are bored.

Michael

wierdscience
10-13-2011, 08:13 PM
(a 210x1500 voest lathe)
As in Alpine Voest?Do tell us more and start a thread on it:)

Evan
10-13-2011, 08:16 PM
The defense rests.

Because that cylinder is below a minimum size it isn't subject to industry standard labeling requirements. Good thing too, since it is incorrectly labeled.

Look on a welding gas oxygen bottle and it will not have a "flammable" symbol. I have both WHMIS and Industrial Gas Handling certification.

Peter.
10-14-2011, 02:42 AM
Apart from that why have a left hand thread on an oxygen bottle when it's usually RH for oxy and LH for fuel?

Looks like a photo for 'spot the mistakes' in training.

Jaakko Fagerlund
10-14-2011, 03:53 AM
goose, your "defence" just likes to ignore things, like the text besides those symbols on the bottle? (The bottle which is, as stated by Evan, incorrectly marked).

Because you are so sure that oxygen is flammable, could you then state the flammability/explosivity range for it, what color flame it produces, what is the heat energy out of it and its flash point?

Probably others want to know the answers to these too, as you are the only one who seems to know about oxygens flammability.

jugs
10-14-2011, 04:45 AM
I was taught that, when in a hole - stop digging, http://www.smileyvault.com/albums/userpics/10404/Diggin_a_hole.gif (http://www.smileyvault.com/)

some of you silly Ba$$tards just want bigger spades & the others keep making them,

But it's fun to read as there's nowt on TV, keep it up lads, as there's nowt on TV tomorrow either :D

PS If you REALLY want to know about oxygen try google or a good basic chemistry book.

A.K. Boomer
10-14-2011, 07:56 AM
Technically oxygen is not flammable -- that is a cold hard fact,
but technically neither are so called flammables without oxygen,
flammability is actually two ingredients and it takes two to tango

--- so I believe in a sense the proper word used to describe oxygen when talking about flammability is the word "Catalyst"
and in fact when it comes to flammability you might call oxygen the almighty trump card... for without it the so called flammability stickers would not exist.

so since oxygen is for the most part in contact with just about everything then there is a catalyst present - now this is the obvious for the world in which we live --- but what isn't the obvious is high concentrations of oxygen, and how normally stuff that wont even burn will explode with it, and it's important to realize that even in it's "contained" concentrated state it still has to be touching something (like the walls of the tank) and if the tanks material is such and if the container is vulnerable (like that little 1.4 oz thinwall that was shown) then one could only imagine the chaos that would ensue if an arc from a welder blew a hole in the tank or somebody set the tank down on a car battery,,,
There's so many cases where you have the entire flammability package right there.
so all you hillbillies getting upset about the labeling of the small oxygen tank being flammable really do need to re-think what the word flammability means --- In the "advanced" way of thinking things through their simply stating that there's an increased chance of flammability due to a much higher level of "catalyst" inside the tank...
The "catalyst" is not in itself flammable - but in some instances even the tank in which it's being kept is... so just in that fact alone the sticker is correct, and just about anything you set the tank around is also subject to the same rules,

It's funny --- just because our atmosphere supports a certain amount of flammability (due in fact to oxygen) then we label products that are flammable in it such, but when the concentrations of oxygen go up and other "products" that normally are not flammable then become combustible then we pay no heed --------- that kind of thinking is wrong - gasoline is not flammable in outer space but of course we call it flammable "down here" and that's all good - but when higher levels of oxygen are used even cast iron becomes "flammable" so should we have movable "flammable" stickers for almost everything that's is placed next to our oxygen bottles? or do we bite the bullet and just put one on the bottle?
remember - technically in outer space you could not label gasoline "flammable" -------- ahhh - so it takes two - doesn't really matter what's the catalyst then does it and in fact the catalyst trumps the flammability card as it can render all flammables inoperative,,, heck we can even see this with certain so called flammables in our own atmosphere at higher altitudes and extreme cold - this entire flammability thing is not an exact science then is it:rolleyes:

here's the other cold hard fact - it takes both a combustible and a catalyst to create the condition for flammability --- and since what's "combustible" varies with the amount of catalyst involved then if your going to start putting stickers on what you "think" is flammable in our atmosphere then Im sorry to tell you that your already recognizing oxygen as part of the flammability component ------- you cannot deny that -- that's a fact - and if your going to recognize oxygen as part of the flammability component then you have to accept that the rules change when you have concentrated levels of this catalyst --------------------- so you need to either have movable flammable stickers that you can place around your oxygen bottle for things like cast iron and stuff or you can just take a short cut and put a permanent one on the bottle ;)

You sticker guys cooked your own goose with that one - the only reason you are labeling stuff flammable in the first place is due to oxygen --- want to argue that fact? bring it --- don't think the rules change when you add higher concentrations of it -- bring that too - im getting fed up with hillbillies that don't have a lick of common sense...

Flammable isn't one or the other pilgrims - it's both - you can't have it any other way...

madmec
10-14-2011, 08:44 AM
Just to keep the war going on (Chips an Beer- better than TV...) my interpretation of that mess:

Oxygen itself is not flammable, but it increases the "flammability" of everything it touches, especially in high concentrations.

Btw: Why had noone stated until now that oxygen is explosive?
Around here they use ordinary Wood soaked in liquid Oxygen as explosive...

And now: Fight! :D

Thomas

P.S.

Just be careful and think about evertything you do- then it wont matter if oxygen is flammable or Dynamite is explosive, handle erverything with care and youre fine.

Evan
10-14-2011, 09:52 AM
Technically oxygen is not flammable -- that is a cold hard fact,
but technically neither are so called flammables without oxygen,

There are plenty of flammable materials that do not require oxygen to create an exothermic reaction complete with heat and light (flame). Chlorine, Bromine and Fluorine will all react with a variety of other elements violently. Magnesium burns extremely well in a chlorine atmosphere.

Our bodies can tolerate pure oxygen because the normal resting metabolism is primarily anerobic. Energy is released by the anaerobic glycolysis reaction. Food is broken down via a reaction with hydrochloric acid which is anaerobic.

Oxygen is not a catalyst. It takes part in the reaction. By definition a catalyst is not consumed or altered but only promotes a reaction.

Evan
10-14-2011, 09:58 AM
Why had noone stated until now that oxygen is explosive?

Because it isn't.

Evan
10-14-2011, 10:04 AM
Possibly the easiest to understand proof that oxygen is not flammable is the fact that if a mixture of a fuel gas and oxygen contains too much oxygen it will not burn. Even a pure oxygen-hydrogen mixture has both lower and upper flammability limits. Too little and too much oxygen and no reaction is possible.

A.K. Boomer
10-14-2011, 10:20 AM
There are plenty of flammable materials that do not require oxygen to create an exothermic reaction complete with heat and light (flame). Chlorine, Bromine and Fluorine will all react with a variety of other elements violently. Magnesium burns extremely well in a chlorine atmosphere.

yes and I hinted along those lines on post 34 --- like I said it makes one re-think the word combustion a little...




Our bodies can tolerate pure oxygen because the normal resting metabolism is primarily anerobic. Energy is released by the anaerobic glycolysis reaction. Food is broken down via a reaction with hydrochloric acid which is anaerobic.

iv always been told by medical people that if we were in a 14.7 psi atmosphere of pure oxygen we would be dead in short order, our lungs would "burn" (not in flames) - they would oxidize. :confused:



Oxygen is not a catalyst. It takes part in the reaction. By definition a catalyst is not consumed or altered but only promotes a reaction.

Yes I was looking for something to provoke thought but technically your right on the money - i'll stick with the "flammable trump card" then... :p

gnm109
10-14-2011, 10:37 AM
You guys got it all wrong. It toke phlogiston to keep a fire going. Spark plugs are phlogiston injectors etc. Then there is captive phligiston like in the bvatteries of flashlights. It's all very scienfific

Buncha morons. Have to explain everything to them.


Forrest: It's interesting that you mention phlogiston. I've been using small quantities of it for years. (It's very expensive). I inject a small amount of it in my parthenogenesis simulator in experiments to attempt to locate the elusive homunculus.

I could tell you more, but I'd have to do something bad to you.

More to the point, I mostly lurk here anymore but this thread caught my attention. Mr. Goose states affirmatively that oxygen will burn. That's nice. It appears that he didn't attend his high school chemistry classes.

This is an interesting thread, however. I can't ever before recall anyone arguing that oxygen will burn. Perhaps this is a first. Keep 'em coming. :D

Peter.
10-14-2011, 11:20 AM
Possibly the easiest to understand proof that oxygen is not flammable is the fact that if a mixture of a fuel gas and oxygen contains too much oxygen it will not burn. Even a pure oxygen-hydrogen mixture has both lower and upper flammability limits. Too little and too much oxygen and no reaction is possible.

Like water?

Bill736
10-14-2011, 11:59 AM
Well, I've been looking for something unsaid to contribute to this smoldering thread, and I believe I have one; Wood itself does not burn . Once heated high enough, the gases given off from the wood then burn. I wonder if that's true with many other materials, such as inorganic materials ?

jugs
10-14-2011, 12:25 PM
Well, I've been looking for something unsaid to contribute to this smoldering thread, and I believe I have one; Wood itself does not burn . Once heated high enough, the gases given off from the wood then burn. I wonder if that's true with many other materials, such as inorganic materials ?

Are you trying to spark off another argument or just inflaming this one http://www.freesmileys.org/smileys/smiley-forum/flamed.gif (http://www.freesmileys.org/smileys.php)

Evan
10-14-2011, 12:49 PM
iv always been told by medical people that if we were in a 14.7 psi atmosphere of pure oxygen we would be dead in short order, our lungs would "burn" (not in flames) - they would oxidize. Refer to my earlier post on that subject.




Like water?

No, Water is a compound which is the ash of a combusted hydrogen-oxygen mixture.

When picking nits precision is a must. :D

Peter.
10-14-2011, 12:51 PM
It is quite funny that we put out fires with oxygen and hydrogen though :D

madmec
10-14-2011, 01:01 PM
Btw: Why had noone stated until now that oxygen is explosive?
Around here they use ordinary Wood soaked in liquid Oxygen as explosive...



Because it isn't.

If you think Oxygen ist inflammable then it must be explosive too, if following the same logic.

Ever filled a plastic Bag with the gas mixture of an extinguished oxyacetylen torch and lighted it up?

Most Rocket explosions wouldnt have happened without Oxygen...

Thomas

Evan
10-14-2011, 01:27 PM
Turn on the oxygen on a welding torch and try to light it.

A.K. Boomer
10-14-2011, 01:31 PM
uuuhhhm ok - light it with what??? :D

Evan
10-14-2011, 01:32 PM
A flint striker.

A.K. Boomer
10-14-2011, 01:39 PM
It's as simple as bondo --- bondo isn't bondo unless you have the hardener ( and don't pull the UV bondo crap on me )

one is a pile of goo and the other a pile of goop - and it takes both to make bondo

the word "flammable" generally works the same way;)

madmec
10-14-2011, 01:40 PM
I am on the side of those who know that Oxygen ist just an Oxydizer and not Flammable or Explosive.

I just try to point out to these people wich think it ist Flammable, that if they think it ist Flammable then it must be Explosive too.

A.K. Boomer
10-14-2011, 01:45 PM
A flint striker.

uuggghh.

How did I know you were going to use that as an example?

is flint immune to oxygen - will it spark in space? would it spark exactly the same in space?

A.K. Boomer
10-14-2011, 01:50 PM
I am on the side of those who know that Oxygen ist just an Oxydizer and not Flammable or Explosive.

I just try to point out to these people wich think it ist Flammable, that if they think it ist Flammable then it must be Explosive too.


it isn't flammable any more than bondo hardener is bondo, but it takes bondo hardener to make bondo - without it the other ingredient to bondo is useless... unless your into goop - then either will work just fine - but don't call it bondo cuz its not -- hope that clears things up for u...

jugs
10-14-2011, 01:57 PM
It is quite funny that we put out fires with oxygen and hydrogen though :D

I've always used petrol ,..............Is that where I've been going wrong. :eek: :confused:

Peter.
10-14-2011, 02:23 PM
I've always used petrol ,..............Is that where I've been going wrong. :eek: :confused:

Nothing wrong with that - so long as you don't mix it with oxygen :D

Gravy
10-14-2011, 06:23 PM
Geeze, guys!

Do you realize that some of the most...ummm..."spirited" arguments in this thread are between people who actually agree on the essential facts?

It's like Jesuits heatedly debating whether the angels on the head of the pin are dancing a waltz or a minuet:rolleyes:

jugs
10-14-2011, 07:25 PM
Geeze, guys!

Do you realize that some of the most...ummm..."spirited" arguments in this thread are between people who actually agree on the essential facts?

It's like Jesuits heatedly debating whether the angels on the head of the pin are dancing a waltz or a minuet:rolleyes:

Right then troublemaker, lets get this straight once & for all :mad: , Facts are NOT essential in any forum debate.............. where would the fun be in that :rolleyes: , next you'll be wanting truth & logic :eek: where would it end - people would become agreeable & nice to each other, & that would cause the world to tilt on it's axis..... then there'd be real problems !!!!!

Remember, my deeply held belief (however implausible) is better than your deeply held belief, so don't you go around spreading facts/logic & spoilling things !!

Evan
10-14-2011, 09:41 PM
is flint immune to oxygen - will it spark in space?

My piezo BBQ lighter will but it won't light oxygen.

jugs
10-15-2011, 02:12 AM
My piezo BBQ lighter will but it won't light oxygen.

Maybe you're using the wrong oxygen mix - TRY THIS (http://www.youtube.com/watch?v=5DDEl7JnWvo&feature=related) :)

Evan
10-15-2011, 03:11 AM
And, for a complete roundup of interesting reactions there is the explosive, triacetone triperoxide (TATP). While it does contain oxygen, when it explodes it doesn't burn or combust. It is a highly unstable solid that decomposes directly to a gas without undergoing an exothermic reaction. Because the gas phase occupies far more space than the solid phase it produces extremely high pressures almost instantaneously. It is nearly as powerful as TNT.

A.K. Boomer
10-15-2011, 07:45 AM
My piezo BBQ lighter will but it won't light oxygen.


No - but the oxygen will "light it" and make the spark different esp. right at the anode of the lighter --- it will aid in burning both contacts - it will erode faster and the spark will look way different.

now you need to tell me your BBQ lighter is super high quality and is platinum tipped...

Evan
10-15-2011, 09:10 AM
No - but the oxygen will "light it" and make the spark different esp. right at the anode of the lighter --- it will aid in burning both contacts - it will erode faster and the spark will look way different.


Umm, they aren't "contacts" since the electrodes are never in contact. Isn't it odd how the sparks generated by a Van de Graaff generator never leave any burn marks on the aluminum globe or even your finger? Contact erosion is a non linear effect. Below a certain energy level there isn't enough energy to ionize the metal from which the electrode is made. The appearance of the spark will certainly change in a vacuum since there is no gas to ionize. The spark will be invisible. In oxygen the spark will be visible but it is much easier to ionize a gas than a metal.

Even so, ionizing a gas is not burning or combustion. It does provide enough energy to initiate combustion providing the gas is a combustible mixture. Pure oxygen is not.

BTW, the electrodes are usually made from tungsten which is extremely resistant to erosion even at very high energy levels. At the level of a piezo generated spark there is no erosion. It is below the threshold at which erosion will occur, oxygen or not.

Forestgnome
10-15-2011, 09:37 AM
Possibly the easiest to understand proof that oxygen is not flammable is the fact that if a mixture of a fuel gas and oxygen contains too much oxygen it will not burn. Even a pure oxygen-hydrogen mixture has both lower and upper flammability limits. Too little and too much oxygen and no reaction is possible.
Actually that's not because of too much oxygen, but because the molecules are too widely dispersed to transfer the heat of ignition from one molecule to the next. A flammable solid in the presence of "too much oxygen" will still burn. If you compress that mixture you mentioned I'ld bet you'ld get a good (or very bad) reaction.

Evan
10-15-2011, 09:52 AM
"Actually that's not because of too much oxygen, but because the molecules are too widely dispersed to transfer the heat of ignition from one molecule to the next." by too much nonflammable oxygen... :)

A.K. Boomer
10-15-2011, 04:58 PM
Umm, they aren't "contacts" since the electrodes are never in contact.

correct, (sorry was in a hurry) - that's why I said anode just before so I think you know what i meant right? - I mean that's why you said electrode -- the only term missing now is cathode and I just said it so it's all good now right???



Even so, ionizing a gas is not burning or combustion. It does provide enough energy to initiate combustion providing the gas is a combustible mixture. Pure oxygen is not.


there's actually some pretty heavy duty controversy on this very topic in the automotive world Evan -- and from some theory of operation guru's --- now im not disagreeing with you - just stating a fact that the controversy exists,

some "claim" that it's impossible for the spark itself to light off the mix - they "claim" that there has to be a small part of the anode that burns up as a sacrificial lamb and it is in this very process that the gasses are ignited... just sayin...




BTW, the electrodes are usually made from tungsten which is extremely resistant to erosion even at very high energy levels. At the level of a piezo generated spark there is no erosion. It is below the threshold at which erosion will occur, oxygen or not.

I don't think their concerned enough with the lack of repetitive nature of the standard issue BBQ grill lighter to warrant the use of tungsten cathodes and anodes...
tungsten isn't as expensive as platinum but it's not dirt cheap either, and since most of your BBQ lighters are only firing off about 25 to 50 (instead of "per second") times a year and most likely being built in china "real" tungsten would be kinda overkill don't cha think??? sooo why are we talking tungsten --- did the rules change yet again???

Evan
10-15-2011, 05:40 PM
What rule change? Saying something like that doesn't make it so.

Tungsten, platinum or iron, it doesn't matter. It isn't relevant because it has nothing to do with the nonflammability of oxgen.


some "claim" that it's impossible for the spark itself to light off the mix

They would be wrong.


there's actually some pretty heavy duty controversy on this very topic in the automotive world Evan

I've noticed that there are a lot of people on automotive forums that don't have physics as a strong point.


now im not disagreeing with you - just stating a fact that the controversy exists,

There is also a lot of controversy over what the aliens do to you when the abduct you.

Bringing up nonsense that you claim to have heard elsewhere isn't exactly a stellar argument.

DFMiller
10-15-2011, 06:09 PM
Now it's at 100 posts.

DFMiller
10-15-2011, 06:11 PM
And no consensus

jugs
10-15-2011, 06:34 PM
Can we make it 200 :rolleyes:

jugs
10-15-2011, 06:41 PM
THIS O2 (http://en.wikipedia.org/wiki/The_O2_Arena_(London)) is supposed to be non flammable............. time will tell, thermic lance maybe :confused:

A.K. Boomer
10-15-2011, 07:32 PM
What rule change? Saying something like that doesn't make it so.

Tungsten, platinum or iron, it doesn't matter. It isn't relevant because it has nothing to do with the nonflammability of oxgen.


First off since were nit picking -- the word is "oxygen" not oxgen --- I have heard it pronounced "oxgen" back when I lived in detroit but two wrongs don't make a right --- secondly -- your not going to try and pin the "non-flammability" one on me - of course oxygen isn't flammable --- I already stated that as "the cold hard fact"

My entire point to all of this is for you and others to recognize that the very reason we call flammables flammables is due to oxygen --- and as soon as you can wrap your brain around that one then you will have to accept the fact that the "label" isn't for just one single thing --- it's for the combination of two substances which can result in flammability - the labels are not for what these substances will do in the presents of chlorine bromine or fluorine - they are labeled what they are due to oxygen -------- deal with it...

Now that you have dealt with that FACT then you are forced to deal with other facts - and those facts and laws of physics dictate to you that when oxygen is in a concentrated state that the available fuel rule book changes and fuels that normally would not be an issue have now become one --- so I could give a rats flying ass if your certified in "gasses" and you "claim" that an oxygen bottle needs no further warnings --- Im telling you your wrong, your logic if flawed,

If the label "flammable" is there due to the potential end result of both the substance and oxygen, then a concentrated oxygen bottle should have the sticker on it two --- "why" ???? not because it's flammable - but because it increases the chances of flammability --- that's the very reason the so called other "substance" has the label on it in the first place.







They would be wrong.

of course they could --- that's exactly what I told you - even though iv read short studies on both sides im not taking sides - I simply don't know --- like I stated - lots of controversy --- want some more ? just ask a few virologists whether a virus is alive or dead --- like I said -- lots of controversy...





I've noticed that there are a lot of people on automotive forums that don't have physics as a strong point.

Iv noticed that everywhere :rolleyes: [/quote]

There is also a lot of controversy over what the aliens do to you when the abduct you.

Bringing up nonsense that you claim to have heard elsewhere isn't exactly a stellar argument.[/QUOTE]

Your a total hillbilly sometimes --- it's not nonsense -- it's in depth studies with things like nano-second camera's and flame front analysis - it's stuff that I would never read but working with my bro building race engines I had to listen to what flavor of book he was reading at the time and I retained a little of it --- Ohh but I forgot --- evan almighty trumps everybody -- even people who have spent a lifetime in their own field:rolleyes:

Gravy
10-15-2011, 07:54 PM
Right then troublemaker, lets get this straight once & for all :mad: , Facts are NOT essential in any forum debate.............. where would the fun be in that :rolleyes: , next you'll be wanting truth & logic :eek: where would it end - people would become agreeable & nice to each other, & that would cause the world to tilt on it's axis..... then there'd be real problems !!!!!

Remember, my deeply held belief (however implausible) is better than your deeply held belief, so don't you go around spreading facts/logic & spoilling things !!


Oh no sir!

If you go trying to inject rationality and factuality into this argument, I shall be forced to demand satisfaction. Kindly choose your weapons and time. Have your seconds make arrangements with my seconds.

I remain deeply respectfully yours, and etc., and etc...

Meanwhile, I'd like to see what Evan and AK Boomer and several other participants could produce if they were to actually co-operate instead of arguing penile metrology.

(Sorry guys...but you have already demonstrated that you can do much better. Stop arguing with each other and get back to actually doing stuff and share the results with the world.)

Otherwise, declare your political party affiliation and give your all to to the divine wind. Banzai! Allahu Akhbar! Kill them all...God will recognize his own.

Or maybe we could go back to the quaint idea of passing wisdom on to the next generation?

Nahhh. Why bother? When I die, the world ends.

I may be feeling just a bit cynical tonight. Do any of you brilliant bastards have an entertaining argument to the contrary?

Gravy
10-15-2011, 08:05 PM
Would all of you guys PLEASE stop nitpicking each other to death and start working together?

It's tremendously frustrating to witness gamesmanship trumping problem solving. This is how our politicians got us into our current disaster. It reminds me too much of 8th grade.:mad:

Okuma2540
10-15-2011, 08:27 PM
I will say this,thanks for the laughs you all made my boring saturday night.
But I will also say the Facts change! until we are almighty and know everything there is no need to argue just give your best answer and respect that others may disagree. Lets have fun and give the best help we can.

Gravy
10-15-2011, 08:32 PM
I will say this,thanks for the laughs you all made my boring saturday night.
But I will also say the Facts change! until we are almighty and know everything there is no need to argue just give your best answer and respect that others may disagree. Lets have fun and give the best help we can.

This may be the best post of the evening.