I don’t have the in-depth metalsmithing experience as some of the
contributors but I have worked in health and safety for a large
medical/industrial gas company and I believe that we all need to
consider the risks associated with everything we do in life -
everything,including doing nothing carries a risk.
Risk is the product of severity of outcome and likelihood of
occurrence. For example as I sit at my laptop composing this email I
am at risk that a fully loaded passenger jet bound for the nearby
London[Luton] airport is at this time plunging towards my home with
all four engines out of action. The outcome would truly be terrible
but the likelihood is quite small so I can place this risk in the
low category and continue with the email. Cutting your left hand
with a graver is more common but the outcome is normally only slight
so that’s also a low risk.
So how does this apply to torch safety in a basement or any other
situation. You cannot have a flame without a combustible gas and
although I totally agree that gases which are heavier than air are
the most dangerous in such a situation as they have no possibility
of venting to free air, lighter than air gas trapped in an enclosed
basement doesn’t have any means of escape either and will still
raise the roof in a dramatic way if ignited.
If we accept that we are going to use combustible gases for
soldering it doesn’t really matter what form of torch you use,
prevention of a gas leak is our major concern.
For the record I also have a range of torches which I have acquired
over the years including a mouth-blown French style torch, a
flamefast needleflame torch with air supplied by an aquarium pump
and a little touch which runs on propane and oxygen. All of the
torches can be used for jewellery but if you need more heat or
greater control over the flame type/size the oxy/propane the little
torch is excellent.
Clearly we need to follow basic measures and I follow this routine:
I turn on the gas at the cylinders at the start of each day and then
slowly open the regulators, then I open and close each torch valve
in turn to purge the lines of gases other than those that should be
there. In addition once a week I use an industrial grade gas
detection spray [ if you are using oxygen ensure that the spray is
oxygen safe and do not use a water/detergent as it contains grease
and can cause an oxygen fire] over the regulator and hose assembly
to check for leaks. If I leave the workshop for any reason or decide
that I will not be carrying out soldering operations for some time I
will back the regulators out to zero cutting off the supply to the
torch. At the end of each day I close the taps on the cylinders and
drain the lines and the regulators before ensuring the gas is turned
off at the torch, at the regulators and at the cylinders.
Replacing the regulators at the manufactures recommended intervals
is sensible as they can contain rubber disks which can harden with
age and fracture. Other measures for gas leaks include the fitting
of an electronic combustible gas detector which will alarm if gas is
present in the atmosphere. One important point - if you are using
cylinders that use a spanner to open and close the valve make
certain that it’s in-place all the time in case you need to carry
out emergency close down.
Of course gas explosion isn’t the only risk with soldering torches
fire is a major risk and we need to think about the possibility of
fire, what could accidentally catch fire, how could we minimise this
possibility and how would we put the fire out or escape - how many
exits are there in your basement. I have an extinguisher and a fire
blanket near to hand. Fumes from the soldering activity also need to
be evacuated.
There is one major risk factor that I have that you could avoid and
that’s the use of oxygen. Oxygen is not a combustible gas as such
but its presence in high concentration greatly assists items that
would not normally burn to do so. In addition its under great
pressure and there is a possibility of severe cold-burn from
escaping gas should you not fit the regulator correctly. I believe
that there are more serious industrial accidents with oxygen than
with combustible gas. However you will need an air compressor or
learn to blow and breath at the same time- a skill that I have never
achieved.
Hope this helps.You cannot escape all risks, just understand what
they are and take action to minimise them.
regards
mike kersley
also waiting for this UK winter to end