Fumes from melting scrap jewelry?

Forum members!!!

Hopefully you are able to help answer an unusual question, or
perhaps point me in the right direction.

I have a client that is in the process of opening a “smelting”
division within his jewelry business, and the city council is asking
for some specific regarding the fumes created. My client
is looking at increasing his scrap jewelry buying, and is simply
melting the gold down into Dore bars using a gas torch for ease of
shipping and assay purposes.

The City Council is concerned about the fumes created during this
“smelting” process, and is looking for research regarding the
toxicity levels of these fumes. I am under the impression that a
majority of the fumes consist of dirt, oil, skin, and perhaps some
zinc, nickel and copper but that is almost negligible.

There will be No acids, No chemicals, just torch melting and a pour
into dore bars. He has all the proper vents, and scrubbers in place,
but the city wants specifics on the fumes before and after they
vented into the air.

Do any of you have (or know any links) to literature, research, etc.
regarding the chemical breakdown of what the fumes consist of? And
the toxicity levels of these fume?

Any help would be greatly appreciated.

Kindest regards,

Miguel A. Rosas

He has all the proper vents, and scrubbers in place, but the city
wants specifics on the fumes before and after they vented into the
air. 

If he already has a functioning business with scrubbers, etc. in
place and he’s not going to be doing anything different, why did he
ask his local government for permission?

For a start off it is not smelting but melting and I suspect that
the council has its wires crossed on this point. There will be no
toxicity measurable by normal methods.

Nick Royall

He has all the proper vents, and scrubbers in place, but the city
wants specifics on the fumes before and after they vented into the
air. 

If he already has a functioning business with scrubbers, etc. in
place and he’s not going to be doing anything different, why did he
ask his local government for permission?

I mean, sometimes it is better to be under the radar. Government
regs are so voluminous, it can take forever to find the one small
paragraph relating to your question. As for me, I’m always melting
down gold and silver scrap and milling it. I use my vent, borax, a
crucible and an ingot mold. There are some fumes, but I find it is
more of the impurities and any old crud that is stuck on old gold,
and my vent, plus an air purifier takes care of the fumes issue.
Never had any problems and no complaints so far.

As for regs, fire departments really don’t want you to have tanks
indoors, and will put up all kinds of obstacles to prevent you or
deter you from installing torches and tanks indoors. I remember
helping the local high school get set up for jewelrymaking, and it
took about a year to satisfy the fire department and Maintainence
with the torch setup. Now that a state-wide craft organization is
going to set up a jewelry/lampworking lab next year, the educational
coordinator wants me to come with her to the fire department to get
“permission” to have tanks. The vent is in place, so that is all set.
I’m not looking forward to the battle.

Joy

I mean, sometimes it is better to be under the radar. 

Well it depends on your country. There’s a lot of financial risk
(and possible imprisonment) to fly under the radar in Australia.

In Australia, it’s the responsibility of the business owner to make
sure everything is above board.

As with our law, ignorance is no excuse. We have to know the
regulations relating to our business.

I’m not saying every business owner is a paragon, but there are
serious risks to consider.

Regards Charles A.