Ventilation & respirator options

I’m returning to silversmithing after many years away & I’d like to
take better care of my health this time around. I’ve been
researching ventilation & respirator options & have found the orchid
& ganoksin archives really helpful, as well as Monona Rossol’s
“Artist’s Health and Safety Guide”, but I’m still not sure what I
need. I hope someone can help.

I’ve begun to do soldering, keeumboo, and liver of sulpher patinas
(not hot) in a small outbuilding separate from my house. I’m about
to build a ventilation system and I’m wondering if i should also buy
a better respirator, as my lungs are quite sensitive. I figure I need
protection from metal fumes, acid gas (warm Sparex pickle), hydrogen
sulphide gas and flux fumes.

I’ve recently begun using paste solder & find it very useful but now
I realize it contains one of the most hazardous forms of flux.
(Fluoride compounds release toxic gas when heated, some of which
turns to nasty acids in the lungs). Are there any paste solders that
don’t contain fluorides? If I stop using paste solder, what Acid
fluxes (chlorides of zinc, ammonium?) do other users prefer?

I was surprised to learn that the respirator cartridges that protect
against chemical fumes are “considered spent after eight hours of
use or two weeks after they have been exposed to air, which ever
comes first.” New filters every two weeks sounds expensive - is an
“Air- Supplying Respirator” more cost effective in the long run?

Thanks!

Susan Ellenton

Hi Susan- Before I retired a few years ago to play with my dogs and
make some silver trinkets, I was an Occupational Safety & Health
person. There a couple of things to keep in mind:

  1. Local exhaust ventilation vented to the outside is the best way
    to protect yourself. The hood or collector needs to be very close to
    the point of generation of the contaminants as exhaust ventilation
    has very little drawing power. As soldering fumes, vapors and gasses
    are heated and will rise, a small hood just above the soldering area
    should work (also needs to be slightly behind the work to avoid
    drawing all the goop past your breathing zone). This eliminates your
    exposure and remember that any respirator adds to breathing
    resistance and makes breathing harder.

  2. General ventilation helps but tends to mix everything up and
    dilute the contaminants before eventually exhausting them from the
    room.

  3. The next protection in order of preference is personal protective
    equipment. A half face respirator designed for welding use would
    probably serve your purposes. Some are disposable and cost around 6-8
    $ each. Using disposables you do not need to worry about cleaning and
    such. A source we used to use occasionally is

  1. Air purifying/air supplied respirators tend to be quite bulky
    (they are nearly always a full face mask with an attached air supply
    line). I would not want to try and work in my dank little studio
    dragging around an air line. Plus they are expensive and you need to
    make sure your air supply is not contaminated.

5… Get a respirator that has a NIOSH TC code, that implies they
have been tested and certified. REMEMBER that the rules and
regulations for respirator use are meant for industrial use and
designed to protect employees using them for 8-10 hours per day over
a 40 year work span and may be vastly more protective than what you
need for occasional soldering.

  1. Store respirators in a sealed Ziplock bag when not in use and
    cartridges should last much longer than two weeks. The traditional
    indicators to change cartridges or respirators is when you can smell
    a contaminant, breathing becomes harder, or the cartridge becomes
    warm or discolored.

Hope this helps.
Jim J