Yes, silicosis is a deadly lung disease. It results from regularly
breathing too much fine silica such as is present in clay and glazes.
However, please keep this in perspective. We need to be informed and use
common sense, but we do not need to be alarmists about it. I have been a
life long ceramics teacher and still work in a pottery shop regularly. I
have no symptoms, but I did ask my doctor for a lung function test to see
if I am developing any problems. After 40+ years of exposure in ceramics
classrooms and in my clay studio I still have lung function that is better
than average for my age.
Here are the "best practices" that I follow for safer and healthier working
1. I use only wet cleaning of clay and glaze areas (sponges, mops, water
hoses). I do not sweep or allow any vacuum cleaning unless the machine has
the special approved filters that are replaced regularly. A typical
vacuum cleaner filter allows passage of the fine silica dust that the lungs
cannot expel. Furthermore, this dust is so fine that after vacuuming it
can remain airborne for 4 days. I know potters who safely locate their
vacuum unit outside with a hole-in-the-wall connection for the vacuum hose.
2. I avoid carpeting in areas likely to get clay on them. When carpet is
vacuumed it pulls dust to the surface where it gets scuffed into the air.
I use pieces of outdoor carpeting (scrap from a miniature golf course) at
my studio entrance. To clean these I use a garden hose or power washer
3. When reworking clay, I do not smash dry clay. I just place the dry
chunks in water. I do not stir. It will turn to mush overnight no matter
how thick the dry pieces are. Leatherhard clay has to dry out first in
order to slake it.
4. I teach students to smooth clay before it gets dry by burnishing and by
smoothing with rubber, wood, or metal ribs, sponges, etc. I keep things
moist and covered with plastic until they are finished. I do not allow
students to work on dry clay pieces. I get rid of all sandpaper or
anything that makes dust. If something gets too dry, spray it with a plant
misting bottle and/or cover with old wet paper towels or cloth and place it
inside plastic bags. If it is done very very gradually, in several days a
totally dry piece can be softened without damage.
5. If I use a glaze sprayer, I use an exhaust booth vented to the outside
and keep my face at a distance, or I do it outside.
6. If I ever have to work in a dusty place wear an approved high quality
dust mask. Sometimes, if I am accidently caught in a dusty place without a
mask on, I hold my breath and move to clear air before inhaling. I do
something else until the air clears.
7. I do not smoke. Two bad things are worse than doubling the hazard
because of the combined interactive effects.
At 09:19 PM 8/7/02 EDT, you wrote:
>Yes Linda. Silica is just sand. Exposure to fine particles of silica
>are associated with the following rather unpleasant diseases:
>Tuberculosis,lung cancer, and silicoproteinosis. For more information on