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fiber raku kilns

updated sat 31 aug 96


John Baymore on thu 1 aug 96

From: Rebekah Shope
Subject: Raku kiln from scratch

Hi everybody,

Several people have expressed interest in hearing about the raku kilns that we
built this summer out of 55 gallon drums.

I am a student at Indiana University Southeast, and we had a class this summer
on low fire ceramics and raku. There were a lot of people in the class who
built kilns according to some ideas that our professor had collected.


Building kilns (of all types) should be a part of every ceramists experiences
(and education). Way to go. Glad to hear that the school is providing that
information. Firing a kiln you have built yourself is a great experience.

I would hope that part of the course included information about the possible
hazards that RCF (refractory ceramic fiber) poses to the person handling it.
Also that appropriate precautions were taken while you were working with it.

MINIMAL precautions while handling fiber for construction (in my estimation)
would be a NIOSH toxic dusts and mists respirator, wetting the fiber blanket
very well before handling to control dusting, and wearing a protective outer
clothing layer (jump suit....thoroughly washed out after use....not with
household laundry) to keep fiber off of your clothes.

Preferably the work is done outdoors. If not, the interior space should have
good general dilution ventilation, and be given plenty of time to "clear" before
being used without a respirator on.

I would never use bulk fiber...... too dusty. The thin felt and woven forms are
less prone to dust. And after it has been fired in place, ripping it out is
even more hazardous both due to increased dusting and to the changes the fiber
undergoes when heated.

While all the study is still not in (RCF use is pretty "recent"), there
apparently is great concern among industrial health specialists that RCF is at
least as hazardous as asbestos upon breathing, and possibly much worse. It is
supposedly confirmed that it causes pleural plaques, like asbestos does....... a
possible precursor to cancer.

Call the refractories company and get the printed handling information and MSDS
on the product........ it's a real "eye opener".

If you talk to people like Monona Rossol at A.C.T.S. (181 Thompson St., NY, NY
10012), which I recommend strongly, the recommended protection while using RCF
is wearing an air supplied "moon suit"!!!!! Like in the movie "Outbreak"!!!!
Or better yet, just don't use it. She can be reached at 212-777-0062.

I have been working with fiber in building kilns off and on since it first
became readily available on the commercial refractories market. I use it much,
much less now....... mostly for car seal gaskets and the like. My current lung
x-rays and pulmonary function tests are normal. However, it took me all of
about 1 day working with the stuff and watching the fine fiberous dust quickly
getting into the air to start with the wetting, the respirator, and the jump
suit. So I have been a little careful all these years. Hopefully it has been
enough .

Thought I'd pass this info along for the less experienced folk here reading this
thread on fiber kiln building. Just in case all the concern is proven
valid.......... better to be forewarned and take some protective actions.


John Baymore
River Bend Pottery
Wilton, NH