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Safety Tips for Oxygen & Gas Tank


#1

M.

Does anyone have any safety tips for the tanks 

5 comments

  1. Secure your tanks so they can’t fall when in use, and the caps
    are on for transport.

  2. Get flash back arrestors for your hoses.

  3. DO NOT USE OIL/GREASE ON THE HOSES, GAGES OR ASSOCIATED
    CONNECTIONS!!!

  4. Never set or let acetylene pressure exceed 15 psig!!! (If your
    using acetylene)

  5. If it makes funny thrumming noises from the hand piece, turn the
    gas off at the bottles. (Not the gage noise you may hear when the
    gages are working, mine on occasion whine)

Terry


#2

A couple more:

Watch that your hand piece doesn’t hit the regulators or possibly
cut a hose when hanging freely with a bur or sanding disc. Depends on
tank location.

Check your hoses periodically for damage.

Check the valve on the acetylene tank itself for leaks periodically
and when you exchange for a refilled one.

Close the tank valves every night and check that they are closed
again before leaving.

I don’t bleed my regulators (most will probably disagree with this
one) because:

  • I don’t hit the bladders with pressure every am (especially the O2
    tank)

  • If I have lost pressure over the evening I know I have a leak in a
    line.

  • Should there be a leak it is the same amount of fuel as if I bled
    them anyhow.

Mark


#3

Does anyone have any safety tips for the tanks I won’t repeat the
other comments posted but here are a few more. Note that I usually
document my sources but these are things I have learned over the past
50 years beginning with metal shop in high school. I believe that my
sources are reliable…

Never lay the acetylene cylinder in its side. Acetylene is unstable
above 15 PSI so the tank contains a medium with the acetylene
dissolved in acetone. (I hear that the medium used to be asbestos…I
don’t know if that ever was or is still true.) Laying the tank on the
side could allow the acetone to run out first if the valve has a slow
leak. Without acetone, the tank is unsafe and could explode.

When tanks are not secured in place by a safety chain, make sure the
regulators are removed and metal caps are screwed onto the tanks. If
you use a welding cart, remember that it can fall forwards are
backwards on the wheels. Install the regulators such that they will
not hit the floor if the cart falls over. It is best to secure the
cart. What you are trying to achieve is to absolutely preclude any
chance of a tank falling over with the force of a blow transmitting
to the tank valve and breaking the valve.

I usually crack the valves shortly before installing the gauges to
blow out any dust for foreign material that might interfere with the
fitting seal… That is, quickly open the valve a little and reclose
it blowing just a little gas out. Careful with the oxygen…it is
very high pressure; only crack the valve a little and close it
quickly. Remember when cracking acetylene, it is a flammable gas.

Never place the body directly over a high pressure valve. The valves
are the weak point of a tank. If the tanks are secured with a chain,
the tank should stay in place if a valve blows, but the valve is a
bullet-speed missle. The main danger from blowing valves is if the
tank falls, when tightening connections or at the plant where they
fill the tanks. Men have been killed leaning over a valve when
bringing a tank up to pressure. Only tighten the fitting connection
enough to prevent leaks. (Leak detection described two paragraphs
down.)

After installing the regulators, open the acetylene valve a quarter
but open the oxygen all the way. Wear safety glasses and never stand
over the gauges when opening the tank valves. If a diaphram blows, it
could blow out the glass in the gauges right into your face.

After attaching the regulators with a new set of tanks, set your
pressure then, leaving pressure in the hoses turn off the regulators
and shut the tank valve and shut off the regulators. Note the
pressures on the gauges and wait 15 or 20 minutes and check the
gauges again. A decrease on the high pressure gauge indicates that
the fitting to the tank is not tight enough (or defective), thus
leaking. A decrease on the low pressure gauge indicates a leak in
the hose fittings, hose, or handle valves.

Do not use soap or leak detector soap around oxygen. Most leak
detector soaps are designed for flammable gas leaks. The soaps are
likely to contain oils, the leak detectors usually contain glycerin
that is even worse. (I impress the grandkids by making a
permanganate/glycerin volcano…Glycerin robs oxygen from the
permanganate and spontaneously combusts. It is used in bubble soaps
to promote bubble formation.) In addition to the possibility of
spontaneous and/or explosive ignition, rubber parts and seals break
down in the presence of detergents. (I know…soap and detergent are
slightly different…however, we can’t be depend on consumer labels
to list ingredients.)

Protect your eyes against UV. Some fluxes cause considerable
emmision in the visible spectrum which require dark glasses for
comfort. However, the flame itself emits UV which doesn’t seem too
bright to look at but is harmful to the eyes. (This is something I
have never paid much attention to when using the Little Torch but who
knows…my vision might be a little better now if I had…The flame
is quite small but with jewelry, the face is quite close to the
flame)

Know your alloys…Oxyacetylene gets hot enough to vaporize toxic
metals such as lead and antimony. It has the potential of producing
more fumes. (Techically there is a difference…fumes are gases from
metals, or so I was told in a college air quality class.) If it isn’t
known jewelry metal be sure of what your are working with. Use care
with the costume jewelry repairs (why bother?)…I have seen some
from “Pot Metal” aka casting alloy which is lead, tin, and antimony.

Your welding supply store should have a booklet about safety when
using the gases. I recommend getting one and reading it. Also, your
welding store clerk will be a wealth of if you ask the
right questions.

Howard Woods
Eagle Idaho


#4

Hi Gang,

I’d like to add 3 other tips to the ones that Terry posted.

  1. Always close the valve on the oxygen bottle COMPLETELY when not
    using the torch. The oxy is under about 2,000 psi when the bottle is
    full & the packing gland around the valve stem will leak. Over time
    this can cause a lot of your oxy to leak.

  2. When using your torch, open the oxygen valve COMPLETELY. The
    valves on oxy tanks have to seats; one for closing the valve &
    another for the valve to seat against when it’s open. The reason for
    the open seat is again the pressure of the oxy. With the valve
    against the open seat, the packing gland does not have to bear the
    pressure of the oxy in the bottle.

  3. Only open the fuel gas bottle valve a maximum of 1 turn. One turn
    on the fuel gas valve will provide enough gas for the torch. The
    reason for this is safety. There are 2 things need for a fire, fuel &
    oxygen. Eliminate any one & the fire goes out. There’s oxygen in the
    air & we can’t eliminate that. In case of an accidental mishap with
    the torch resulting in a fire. he quickest way to put out the fire is
    eliminate the fuel. If the fuel valve is open 1 turn or less, it
    doesn’t take long to eliminate it.

  4. Always close the valve on the acetylene/propane bottle when not
    using the torch. The pressure of the fuel gas isn’t as great (about
    500 psi max), but a closed valve doesn’t leak!

  5. After closing the valves on the oxy & fuel bottles, Drain the
    lines from the bottle to the torch Open the torch valves one at a
    time & watch the pressure gauges on the regulator. When they both
    read 0 the line is purged. Drain the oxygen line 1st. Because it
    usually runs at a higher pressure, a plugged or partially plugged
    torch tip could cause some feed back into the fuel line.

  6. Leave the valves on the torch open when the torch is not in use.

Dave


#5

Mark,

I agree with you, with this addition. Your Oxygen tank is very
dangerous. You could get a flash fire with a leak. If your work area
is on fire, the fire department fears your O2 tank more than the
acetylene.

With acetylene you need an oxidizer, where the O2 is the ozidizer.
The acetylene bottle may burst and maybe feed the fuel source of the
fire, the O2 will make it burn hotter and the fire will spread
rapidly.

An automotive shop that have a O/A torch with medium sized bottle
caught fire. The O2 bottle weny off like a rocket, while the
acetylene bottle just ruptured.

Jerry


#6

See my article at Ganoksin on gas handling for further

best
Charles


#7

Hi Folks,

I’d like to say that I have been using an oxy/acetylene torch for
more than years. Thanks for this thread on safety tips. While I knew
most of the I was surprised by the stuff I didn’t. Some
of it was “DUH, why didn’t I think of that!” The was much
appreciated.

Jenny Levernier
jmml designs
Minneapolis, MN


#8
I'd like to add 3 other tips to the ones that Terry posted. 

always more to add! :wink: here’s two more

a) when done for the day and bleeding off the gas burn off the fuel,
don’t just let it bleed out. Neither acetalene or propane is
something you want floating around on your floor waiting for a static
spark!

b) when all oxygen and fuel is bled off unscrew the valves on the
gauges out all the way. if you don’t the mechanism will fail muuch
sooner requiring replacement or rebuild of the assy…a properly
treated gauge assy will last for many many years. much longet than
your hoses…

oh! yes Hoses!!! replace when abraded or they start cracking. I
learned this with heavy welding hoses, and am not sure if there
really is a way to confirm with the a-size? hoses usually used with
the “smaller” torches used in jewelry.


#9
Your Oxygen tank is very dangerous. You could get a flash fire
with a leak. If your work area is on fire, the fire department
fears your O2 tank more than the acetylene. 

A leaky oxygen tank won’t START a fire. it only will make an
existing one burn hotter and faster. You can leak oxygen all you
like, even with an ignition source like a pilot light or spark, and
unless there is some fuel already there to catch fire from that
ignition source, the oxygen won’t have much effect, other than
perhaps to make a pilot light burn hotter too. The big danger from
an oxygen tank, as opposed to an acetylene tank is the pressure.
Oxygen tanks, when newly filled, are sitting there with over 2000
pounds per square inch pressure. If you catch one in a fire that
might cause it to burst from yet increased pressure from the heat,
then the result is not a ruptured tank, but the release of all that
pressure. Might as well have a bomb go off. The tank explodes. This
would be true even if the tank were inert gas. Now, if the cause of
an oxygen tank exploding is an existing fire, then not only do you
have that explosive force being release, but it will then suddenly
and dramatically increase the ferocity of the existing fire. The fire
department thus has good reason to be concerned with an oxygen tank
that’s in the neighborhood of a fire. But this is very different from
any risk posed by a leaky oxygen tank. A small leak in an oxygen tank
is not likely to do very much unless there is an existing fire
already. By itself, it doesn’t start fires. The atmosphere does not
normally contain anything that will burn. So a pilot light, for
example, might burn quite bright and hotter than normal, but with no
harm done, since there may not be anything flammable in the vicinty
for that now hotter pilot light to ignite. With higher concentrations
of oxygen in a room, such as you might get with a really rapid leak,
then things that are flammable will be easier to ignite, but they
don’t automatically (with a few exceptions) ignite on their own.

Now in the case of a fuel gas like acetylene, the situation differs.
If an acetylene tank leaks, and lacking ventillation is able to build
up a concentration of gas in a room, then by combining with the
oxygen already in the atmosphere, it can be explosive. Any ignition
source, such as the small spark when an electrical switch is thrown
or a motor runs, not to mention actual flame sources like pilot
lights, could then ignite an explosion. But even this is not always
easy to arrange, since acetylene dissipates quite rapidaly, and if a
room has any sort of decent ventilation, then it will be difficult to
get a sufficient concentration of acetylene in the air to exceed the
minimum amounts needed for ignition. And while logic might suggest
that an acetylene tank would be very dangerous in a fire, again the
oxygen tank in that situation might exceed the risks of acetylene,
for two main reasons. One is that the degree of combustion or
explosive force that can occur is limited not just by the amount of
fuel, but also by the amount of available oxygen. If you’ve got a
nice hot building fire going, enough to rupture an acetylene tank,
then the existing fire may already be consuming much or most of the
available oxygen. Adding more fuel, even in the form of an explosive
fuel gas like acetylene, might not actually accelerate the fire as
much as you’d think, since it can only burn at a rate determined by
the amount of oxygen it can combine with, and any oxygen it burns
with is then taken away from the oxygen available to take part in the
original fire. Certainly, it would not be a good thing, but it might
in situations of a close environment like an indoor fire, be somewhat
self limiting. Recall that oil well fires are often put out by use of
explosives, that when detonated use up all the available oxygen at
the well fire, thus depriving the oil of the oxygen it needs to
burn, actually putting the fire out with another fire (the
explosion).

The other thing to keep in mind about acetylene tanks is that,
unlike oxygen tanks, they are not under high pressure. You might
rupture them in a fire, releasing all that fuel gas, but they’re not
going to quite so violently explode from the pressure in the tank
because the acetylene is stored in the tank by being in solution in
liquid acetone, rather than being compressed to high pressures. This
also limits, somewhat, the rate at which the acetylene would be
released in the event of a rupture, since it has to come out of
solution. That’s still pretty fast, but not the equal of the explosive
release of an oxygen tank bursting.

While any fuel gas container has it’s safety risks, all told,
acetylene is not that bad, at least not as compared to one specific
danger with propane, another popular bottled fuel. Propane is also
stored as a low pressure liquid, so again, the high pressure of the
tank is not a risk. But the sheer volume of propane that fits in a
tank is much more than an acetylene tank can hold. Plus, and
importantly, propane not only dissipates in air at a rather slow
rate, but it is also heavier than air, tending to sink to the floor
and “pool”. That means that a leaky propane tank might build up an
explosive level of gas at floor level, with only modest amounts of
gas at “nose” level, and since things like furnace and water heater
pilot lights tend to also be at floor level, basement workshops run
the risk of a small propane leak being able to build up an explosive
mix at floor level without being noticed in time, and the result can
literally “raise the roof” and redecorate your yard with the remnants
of your house… Add to this potential that many propane tanks are
fairly cheaply made affairs, easily refilled at lots of filling
stations where the tank may or may not be checked for condition (You
think the kid at U-Haul refilling your propane tank knows what to
look for?), a tank can sit around a workshop sometimes for years
between fillings, getting rusty, maybe developing a leak…

For my money, I’d rate the 20 pound propane bottles as the higher
danger between acetylene, oxygen, or the propane tanks. Just my
unscientific opinion.

Now, that said, for the record I’ll also mention that my own
workshop torches are fueled by a propane tank, exactly as warned
against here. I’m very careful to be sure the tank, when refilled
about every year or so, is new or in new condition. I have both the
tank shut off valve and secondary shutoff valves between the tank and
the torches, reducing the risk of a leak. And I installed a propane
detector next to where the tank is stored, hooked up to my alarm
system, so if the detector sees a leak, I get a warning long before
it could reach an explosive level. Is this totally safe? No. But I
like it better than running the propane line in from an outdoor
location, given the wet and rusting nature of Seattle’s climate in
winter. I might be better using bottled natural gas instead of
propane, since natural gas is not heavier than air, and dissipates
faster. The main thing, for safety, is that I’m very aware of the
dangers of this system, and take great pains to be sure it’s working
properly, shut off completely when not in use, and all the rest. I’d
be happer if the house had a natural gas line I could use, but it
doesn’t. Ah well. Nothing in life is totally without risk, but I feel
I’ve minimized that risk in my own case. Still, I’d hesitate to
recommend this setup for anyone else, since I’ve no idea whether they
would also be as paranoid and careful with the system as I am.

Oh, and as for my oxygen tank, it frankly doesn’t worry me too much.
Not like the Propane does. It’s securely chained in position, so it
cannot fall over (a common cause of accidents with oxygen tanks,
including a cause in those building fires when whatever supports the
tank burns and fails, allowing the tank to tumble and crack open the
neck…)

cheers
Peter Rowe


#10
when done for the day and bleeding off the gas burn off the fuel,
don't just let it bleed out. Neither acetalene or propane is
something you want floating around on your floor waiting for a
static spark! 

I think that it is dangerous to burn the fuel when bleeding the line.
I called Smith about this when I started teaching at a school where
this was the habit. They confirmed my suspicion that this is a
dangerous practice. It is best to use ventilation to get rid of the
fuel that you are bleeding out of the line. If it is burned while
bleeding, the flame can go back into the line, the gauge, etc.

Cynthia Eid
http://www.cynthiaeid.com


#11

I as always seem to agree with Peter’s extensive correct knowledge
of the things he works with and I do with this as well. I worked as
an Engineer and in operating management in the industrial gas
industry for well over 40 years. I was a going to make a similar
observation on oxygen cylinder dangers but just didn’t comment. Full
High pressure cylinders of all types cam fail ripping open in an
external fire, This fire never appears to originate with the cylinder
that fails but with an external fire often caused by trash. Fuel gas
cylinders are a bit different but fires they get involved usually
have started in an external fire also often in trash. Acetylene is
the only fuel gas approved for use in shipboard use for the density
reason. You need to be careful with acetylene cylinders - They first
need to have a good appearance. If they are ill maintained and rusty
they may have other problems and all vendors do not take good care
of these cylinders. Don’t accept bad looking ones. These cylinders
have fusible relief plugs that melt at relatively low temperatures
(say 212F) which relieves the contents and prevents over-pressure.
These sometimes leak – there are varying numbers of these depending
on the cylinder type- they can be located near the valve and also in
the cylinder bottom. Visual condition and Leak checking with soapy
water will find these. A thin soapy water solution is fine and has
been used for years. The common dishwashing detergent JOY or Dawn is
fine for this. The solution should be thin and doesn’t need much
"soap" it can be applied with a soft brush (the small cheap chip
brushes work fine ) or a spray bottle. For years the original Ivory
soap was the base of choice now I say JOY. Soapy water with Ivory
soap was even the compressor lubricant for High pressure 3000 psi use
in my time. I am sure it is still used some places in the world
today. Not much in the US if at all. This only supplements Peter’s
advise not replaces it.

jesse