Oxygen tank hit by bullet, results?

[Coronach]

Sometimes the chemistry gets you , sometimes it's the physics.

Best quote of the thread so far.

Mike

 

[hso]

You do need Fuel, a souce of ignition, and oxygen to get something to burn, but Oxygen itself does not burn. It supports and accelerates burning. To kill the mistaken idea that Oxygen is flammable let's look at what the manufacturer says.

Fom Air Products, one of the largest suppliers fo oxygen to industry.

===========================================================================
Physical/Chemical Characteristics
===========================================================================
Appearance And Odor: GASEOUS OXYGEN IS COLORLESS AND ODORLESS.LIQUID
OXYGEN IS PALE BLUE AND ODORLESS
Boiling Point: -297F,-183C
Vapor Density (Air=1): 0.08279
Specific Gravity: 1.14
Solubility In Water: MODERATE
Percent Volatiles By Volume: 100
===========================================================================
Fire and Explosion Hazard Data
===========================================================================
Flash Point: NONE
Extinguishing Media: NONE SPECIFIED BY MANUFACTURER.
Special Fire Fighting Proc: OXYGEN IS NONFLAMMABLE, BUT SUPPORTS AND
VIGOROUSLY ACCELERATES COMBUSTION OF FLAMMABLES. TO FIGHT FIRES, SHUT OFF
SOURCES OF OXYGEN AND FIGHT FIRE.
Unusual Fire And Expl Hazrds: OXYGEN SUPPORTS AND VIGOROUSLY ACCELERATES
COMBUSTION OF FLAMMABLES. SOME MATERIALS WHICH ARE NONCOMBUSTIBLE IN AIR
WILL BURN IN THE PRESENCE OF OXYGEN.
===========================================================================
Reactivity Data
===========================================================================
Stability: YES
Cond To Avoid (Stability): MATERIALS WHICH BURN IN AIR WILL BURN VIOLENTLY
IN ATMOSPHERE RICHER THAN APPROX. 25% OXYGEN.
Materials To Avoid: ALL FLAMMABLES, ESPICALLY PETROLEUM PRODUCTS, ASPHALT,
OTHER VOLATILE FLAMMABLES.
Hazardous Decomp Products: NONE SPECIFIED BY MANUFACTURER.
Hazardous Poly Occur: NO
Conditions To Avoid (Poly): NONE SPECIFIED BY MANUFACTURER.

 

[MechAg94]

Oxygen liquefies at very low tempertures. O2 has a boiling point of -297 F at standard temperature and pressure. Nitrogen has a boiling point of -320 F. You can't just compress them see them liquefy like propane, though compression is used to generate the refrigeration to liquefy those gases. Trace Argon in the air has a boiling point of -302 F. At higher pressures, those boiling points are higher, but they are still in the cryogenic range and require special vacuum insulated cylinders.

I work for an industrial gas company that builds and operates air separation plants. We have all sorts of safety and design rules for use and handling of oxygen. One example is that you can't smoke within 30 minutes or more after being around oxygen equipment. Oxygen can be trapped in your clothing. I have seen a safety test of a wire doll with clothes that had O2 gas sprayed on it. A lit match was dropped underneath and it went up like a torch in a couple seconds.

The best thing to remember is that ANYTHING will burn in a high oxygen atmosphere. All you need is an ignition source since the metal is the fuel. Aluminum, steel, stainless steel all burn in O2 in the right conditions. Copper/Nickel alloys don't tend to support combustion in O2, but they are more expensive. We typically design our systems to remove contaminants and use the right materials at points were ignition is likely.

I have see the results of 2 Oxygen compressor fires and they are not pretty. They happen really fast with molten metal sprayed everywhere.

The Compressed Gas Association defines an elevated Oxygen atmosphere as 23.5% O2. Normal air is about 21% O2. It doesn't take much additional O2 in a confined space to create problems. On the other side, the low limit for asphyxiation is about 19%. I think 19.5% is usually the alarm point.
NASA, the CGA, ASTM, and other groups and companies have done a great deal of testing over the years on the dangers of O2. Most of it is public information.

 

[middy]

You do need Fuel, a souce of ignition, and oxygen to get something to burn, but Oxygen itself does not burn. It supports and accelerates burning.

That's technically true, but it sounds kind of silly considering that "fire" and "burning" are nothing more than rapid oxidization.

Kind of like saying that water can't get wet, but it supports and accelerates wetting.

Oxygen doesn't just support and accelerate burning, it is the very essence of fire. Oxygen is amazing stuff, it just needs the slightest excuse to start busting the electrons off of nearby molecules and bonding with them. It's amazing that we live on the stuff.

 

[Bob F.]

26: Back n the day the only ambulances were run by funeral hopes in most areas. You're just too young to remember. Everything was either DOS or load-'n-go! Sometimes drivers were not even first aid trained.

Know a Navy dive-master (retired) who had a kid killed loading tanks without a safety cap. Tank was dropped and neck broke off on truck's tail-board. Wound from the valve was through-and-trough, COM. Killed instantly. D-tank (I think) did extensive damage in irregular path including cinder-block walls and vehicles.

LOX on asphalt will burn explosively if stepped on I'm told, Not desire to prove that first hand. Somebody else knows for sure, let me know.

Stay safe.
Bob

 

[Brian Williams]

Do a net search for charcoal and oxygen and look for George Goble an engineer who likes to light his charcoal briquets with a lit cigarette and liquid O2

 

[Davo]

Im gonna have to agree with true blue. I too have thought of actually performing this test, but I dont think the dangers both from fire and to others is worth it. Im sure its been tested somewhere, sometime.
And Scout26, I agree an ambulance at a funeral home sounds like a conflict of interest Actually it used to be quite common, as the hearse would do double duty as an ambulance in the days before vans were modified. The ambulance/hearse attendants would get a call from the local hospital, swing by to pick up a nurse, and than go to the location they were needed. We have come a long way.

 

[JonnyB]

Do a net search for charcoal and oxygen and look for George Goble an engineer who likes to light his charcoal briquets with a lit cigarette and liquid O2

Brian:

I saw that one years ago. Who else but a bunch of engineering geeks could do such a thing? What a hoot!

JB

 

[mcosman]

Also a little off topic:

On the fourth of July we take a pan of soapy water, oxy-acetalyne torch on an oxygen rich flame, extinguish the flame and blow bubble in the soapy water. You only want to have about 1 cubic inch of bubles max! stand back and throw a match at it. Beats the crap out of any fire cracker, and no shrapnel to boot. Don't go overboard with this, I have heard of guys killing themselves.

By the way, I was raised by a pyro-physiscist-engineer-greatestdad. Oh the stories....

 

[jtward01]

WARNING !!! Thread Drift.

Rickstir, why, pray tell, would a funeral home have an ambulance ????? It's either entirely pointless or a conflict of interest ????

Many years ago the funeral homes were the only ones who had a vehicle - their hearse - that could transport someone in a supine position. Eventually the mfgs. started building dedicated ambulances using the same Cadillac chassis that was used for the hearses.


Eventually, regulations requiring training and licensing of drivers and attendents, and requirements for expensive new equipment forced the funeral homes out of the ambulance business.

I worked in everything from Cadillacs to the current van and truck style ambulances and I still think the Caddy was the best ambulance ever built, however they just didn't have enough storage to carry all the gear that a modern ambulance needs to have.

 

[Rockrivr1]

"LOX on asphalt will burn explosively if stepped on I'm told, Not desire to prove that first hand. Somebody else knows for sure, let me know"

This is a true statement. Liquid O2 is very dangerous when in the presence of any type of grease, petrolium etc. When I was in the Navy, I worked on f4s and FA-18s. They each had a removable liquid O2 tank that needed to be filled often. It was the primary air source for the pilots. Every time the plane landed you'd take the tank and bring it over to a guy who would refill it like a propane tank. Sometimes if the guy wasn't paying attention the tank would overpressurize and it would release some liquid O2. They alway loaded on a clean piece of aluminum so there would be no explosions.

One day a tank leaks some liquid O2 and the guy loading it says "watch this" and he stomps a small bubble of it with his boot. Of course bottom of boot has a lot of grease on it and BAM there a mini explosion under his boot. The funny thing though is that it made the guys leg go flying up and his knee hit him in the mouth. Knocked some teeth out. lol That day it was funny.

One time it wasn't was when a tank really was over pressurized and I guess those guys are told to fling the tank overboard if it looks really bad. Well, the guy loading the tank did and man what an explosion when it hit the water. Must of been some grease or petrolium in the water. Whatever it was it was BIG! Kinda gave me a warm fuzzy feeling seeing my bunk was over the plant that made the liquid O2.

 

[Kurush]

You do need Fuel, a souce of ignition, and oxygen to get something to burn, but Oxygen itself does not burn. It supports and accelerates burning.

You do need an oxidizing agent, a souce of ignition, and fuel to get something to burn, but gasoline itself does not burn. It supports and accelerates burning.

You do need an oxidizing agent, a souce of ignition, and fuel to get something to burn, but wood itself does not burn. It supports and accelerates burning.

It is very simple:
fuel + oxidizing agent + heat = combustion product + more heat

It does not matter which component we are talking about, both the oxidizing agent and the fuel undergo a chemical reaction and then release heat. They therefore "burn". All your argument is doing is redefining "burning" to mean "reduction" which is an idiosyncratic definition.

 

[wingnutx]

thinking vasealine to be inflamable

in·flam·ma·ble ( P ) Pronunciation Key (n-flm-bl)
adj.

1. Easily ignited and capable of burning rapidly; flammable. See Usage Note at flammable.

 

[mcosman]

in·flam·ma·ble ( P ) Pronunciation Key (n-flm-bl)
adj.

1. Easily ignited and capable of burning rapidly; flammable. See Usage Note at flammable.

I stand corrected. Insert - Non-flammable

 

[mcosman]

Inflammable and flammable both mean 'capable of being set on fire' or 'easily set on fire', so they're really the same, rather than similar, in meaning. This sense equivalence is confirmed by dictionaries, though some writers insist that flammable means 'combustible' and inflammable means 'explosive'.

Inflammable dates from the early 17th century. Originally its opposite was noninflammable, but now we use the easier term nonflammable.

In the word inflammable, the prefix in- functions as an intensive-it indicates increased emphasis or force. But because this prefix can also mean 'not', inflammable could mistakenly be interpreted as meaning 'not flammable.'

-Taken from randomhouse word of the day.

 

[RyanM]

Ay yi yi. This is almost as bad as the old "accuracy vs. precision" thing.

 

[Kurush]

Ay yi yi. This is almost as bad as the old "accuracy vs. precision" thing.

Or the clip vs magazine thing

I think I'll go load some bullets into my AR-15 clips now. Clip clip clippity clip clip!

 

[MechAg94]

Liquid O2 on Asphault

We have the same safety concern for Liquid Oxygen truck loading areas as well as the liquid oxygen pumps area near the storage tanks.

We had a fatality at one plant years ago where a guy was standing next to a pump that had a liquid oxygen leak. The motor start button was right near the pump and I believe the start attempt provided the ignition. They only part of his clothes left unburned were the steel toes and some of the soles. He managed to walk a few feet away before collapsing. The sad thing about burns like that is survivors don't always die right away, it can take a few days.

They say that all the safety rules in the chemical industry are written in blood. That is probably true of most industries. Some of the best speakers on the importance of safety are the survivors. I remember seeing a safety video of a guy who was severely burned talking about the treatment he had to get at the burn center to recover. Makes your skin crawl.

 

[Bullet Bob]

Around 1972 I was a medical corpsman in the USAF stationed at Shaw AFB, SC. TSgt Jack Armstrong, my supervisor and the person who really got me into shooting handguns, took some almost empty, small, disposable oxygen tanks to the local shooting pit, and we shot them with several guns. At about dusk, when hit with Jack's .308, it was a beautiful sight to see. I guess the bullet created some sparks when it hit the metal canister, and of course a .308 ruptured the small tanks quickly. Quite a nice fireball.

I'm certainly game to do it again if anyone close by has the material and time!

 

[Jim K]

I once read a "suspense" story where the bad guy was in a hospital. He had one hand on the valve of an oxygen tank and a cigarette lighter in the other. The police chief would not let anyone try to capture him since "if he sets off that oxygen, all the air in the hospital will go up and this town will look like Hiroshima."

I suspect the writer flunked Chemistry 101.

(The beautiful nurse and the intern managed to capture the guy before he could set off the nuclear explosion! Romance, needless to say, saved the day.)

Jim

 

[G T]

Lesson on fire

A couple of people have said this so far, yet I wonder, have you ever started a fire in an oxygen free environment? Of course you have not. While Oxygen itself is not flamable, oxygen is an essential for fire. The more of it the more likely any other fuel is to burn. None of it and the fire will go out. This is why smothering a fire works to extinguish it, this is why many chemical fire extinguishers work. I believe one of these chemical fire extinguishing substances is called Halon; it is used in computer rooms and pretty efficiently removes oxygen from the air if released into an enclosed space, thereby extinguishing fires.

This is incorrect. Halon, in its various forms (1001, 10001, 1011, 1202, 1211, 122, 1301, 104, 2402, etc.) do not work by displacing oxygen from the room --- if they did, anyone in the room would suffocate. This is why carbon dioxide extinguishing systems (which operate by this mechanism), are required to be on a time-delay after many loud, obnioxious alarms are sounded allowing any occupants to egress from (i.e. leave) the room before the gas discharges. More specifically, air contains about 23% oxygen by mass; humans tend to die around 12% (IIRC) and fires can burn as low as 5% --- so lowering the oxygen concentration will first kill the lives you are trying to protect with the system in the first place. The design concentrations for Halons were in the 3--4% range for ordinary combustibles.

Halons are no longer used because they supposedly deplete the ozone layer --- in fact, since production was banned by the Montreal Protocol in 1993, a significant black market for Halon has emerged. The reason Halons were used in the first place was because they were nonconductive, "total-flooding" agents which could fill a computer room, extinguish a fire and not require the use of damaging water. Also, halons were non-lethal in the concetrations and exposures anticipated for fire suppression purposes. Furthermore, the gaseous delivery meant that halon could penetrate into places water would be shielded from --- such as computer cabinets --- and extinguish fires there.

For the curious, Halon is a halogenated hydrocarbon. Halon 1301 (bromotrifluoromethane), probably the most prolific, has the chemical formula C F3 Br where the three fluorines and one bromine are branched from the central carbon atom, forming a + shape. Halon extinguishes fires mainly by tinkering with the actual chemistry of combustion --- the halogens (fluorine, chlorine, bromine, iodine) have this effect.

Also, halons also dilute the air somewhat around the fire like nitrogen (77% of air). That is, the heavy halon molecule has to to be heated along with the oxygen and nitrogen in air entrained in the fire. This has a cooling effect on the fire, slowing the combustion reaction. This also partially explains why burning in pure oxygen --- in the absence of nitrogen, itself a diluent --- produces hotter, faster combustion.

Fire protection engineering lesson is concluded.

 

[Tom C.]

I was a military pilot. We had a liquid oxygen tank for crew breathing. To demonstrate the hazards of LOX, they made a safety movie about it. The final segment was dropping the tung of a flight deck vehicle on a glove that had some LOX on it. It literally blew up. They then had photos of the guy who demonstrated that. He was a live crispy critter.
Tactical military aviation is getting away from LOX and replacing it with an osmotic filter to filter out O2 from customer service bleed air and send enriched O2 to the crew. The nitrogen rich remainder is then used to pressurize fuel tanks. It helps to reduce the likelihood of fuel cell fire in the event of battle damage.

 

[Gewehr98]

Oxygen is the oxidizer used to sustain combustion, period.

Try to ignite the oxygen in an oxygen-rich test environment where there is no combustible material, and see what you get. Nothing. Zip. Nada. Maybe the match you threw in there will burn out faster, but that's it. Oxygen is non-flammable, in and of itself. The MSDS even reflects that. Chemistry doesn't lie.


Now, for the halon thingy:

Halons are no longer used because they supposedly deplete the ozone layer --- in fact, since production was banned by the Montreal Protocol in 1993, a significant black market for Halon has emerged.

No need for a black market. As reconnaissance aircrew for the USAF, I guarantee that Halon, particularly 1211, is still very much in use. Nothing better has been found for fire suppression aboard large military aircraft, so we still use the stuff. I have no less than 4 good-sized Halon 1211 fire extinguishers on my airplane alone, as do all the RC/WC/OC-135 variants. If you throw the 500+ KC-135 variants in the fleet into the total Halon extinguisher inventory, you're looking at 2000+ Halon extinguishers still in service. Then there are the C-5, KC-10, B-52, C-130, and C-141 variants out there with their onboard handheld extinguishers. Just keep an eye open for that peculiar yellow/green extinguisher bottle!



(3 more, and it's over...)

 

[jtward01]

I was a military pilot. Tactical military aviation is getting away from LOX and replacing it with an osmotic filter to filter out O2 from customer service bleed air and send enriched O2 to the crew. The nitrogen rich remainder is then used to pressurize fuel tanks. It helps to reduce the likelihood of fuel cell fire in the event of battle damage.

Did you mean compressor bleed air?

 

[atomchaser]

In the late 60's I worked for a funeral home and we had an ambulance. We would re-fill our o2 tanks at a local firehouse. One day my attendant dropped a tank after filling. The regulator broke and off she went in a fishtale path accross the floor of the firehouse and partway down the driveway before she gave out. Very impressive. One of the fireman said it was a good thing it wasn't the big their big tank!

serious conflict of interest..or why would you need to administer 02 to a corpse? Beware of EMT's in black Brooks Brothers suits!