Students can be instructed to use wet sponges to immediately spot clean any drips around the wheels and pick up all crumbs before they get walked on.  Train them to carry two clean sponges from the sink so the first sponge gets the mess and the second sponge removes the residue. This can significantly stretch the times between total cleaning.

Some potters have a shop vac outdoors with a small pipe through the wall for the vacuum hose.  They use a shop vac that can have water in it and it can pick up water.  By locating it outside, any dust that might be blown out of the vac is dissipated outside.  I would only use a vacuum if it is outdoors where the dust can dissipate. 

who is at risk?
Teachers are much more at risk than students because of the time spent in this environment.  However, students need to learn proper respect for the dust in case they  decide to continue working in clay over a period of years. 

If cleaning makes any dust at all, it should be done at the end of the work day so the dust settle out of the air before the space is inhabited.

never allow sandpaper
In the days before they knew about the hazards of clay dust, the workers who sanded the mold marks from greenware in pottery factories died within a few years from silicosis. Never work on dry clay. Smooth it by sponging. If it is too dry, spray it with water.  It can be wrapped in plastic, and sprayed again until wet enough.  Do this gradually, but repeatedly to avoid expansion cracks from the water.  With a bit of practice, it is possible to completely soften a piece with damp cloths inside the plastic wrapping. 

how to rework scrap clay without making dust
It is difficult to mix clay without making any dust.  Moist trimmings should be immediately placed in a plastic garbage can of water. 

Once the clay is mush, you can take extra water off the top.  I dip the water into another garbage can so the suspended clay is not lost, but just becomes part of the next batch. 

The thicker mush is then dried until it is ready to wedge.  There are various ways to dry it.  Place it several inches thick on any porous material.  I like canvas better than plaster because I hate it when small pieces of plaster get in the clay.  The pieces of plaster expand after firing.  This breaks the pots or causes pieces to pop out of the surface.  Canvas on the webbing of an aluminum lawn chair allows the clay to dry from the bottom as well as the top.  Porous bisque trays would also be safe for drawing out extra water.

When clay is nearly dry enough, make it into large arm size coils.  Make big arch forms from them and set them around the studio overnight to firm up.  When  the clay is ready, seal it in plastic until you are ready to use it.

mixing from dry clay without inhaling dust
There is probably no way to mix clay from dry clay and be absolutely dust free.  Either buy premixed moist clay or use good a good exhaust fan and a very good dust respirator.  By working very carefully, you can minimize the dust as you mix clay. 

Exhaust fans must blow the dust outside and be powerful enough so that you can see the dust moving away from you.  There must be a source of clean air.  If you have to place your face in the dust, do not inhale until you are back in clean air. 

If you are using a power mixer it should be placed between you and the exhaust fan.  If the mixing or other dust making activity is done in the working studio, plan do it at the end of the workday so airborne dust settles before you inhabit the studio again.

Never dump dry clay into the mixer or into a mixing container.  Place dry clay all the way down in the container.  Do not drop it.  Put it gently and slowly into the mixer or container so no dust raises from the event.  Close the mixer before running it.  Be patient.  Retire to a clean area while the mixer runs.  When opening a mixer, back off, hold your breath, and wait in a clean air place while the air clears at the mixer.

Launder clay clothing often.  Remove clay shoes before entering house.
Do not wear clay cloths in the house.  Keep some environments totally clay free.

• Use a separate building, rather than in the house where you eat and sleep. 
• Provide an outdoor area or a separate and properly ventilated room for clay mixing.
• Provide an outdoor area or a separate and properly ventilated fireproof room for firing.
• Make it easy to hose down the floor.  A smooth sealed surface is easier to clean.
• For areas that cannot be hosed off, equip it with a vacuum cleaning unit that is located outside with inside pipes and hoses.

table covers for clay work in art classes

• Clay slabs often stick to the surface on which they are formed. Therefore, rolling slabs between two canvases allows the canvas to be peeled off of the clay to release it.
• Coils cannot be rolled on a smooth table without sticking.
• Provide canvas table covers that can be sponged clean and rolled up or stacked away. Do not brush them or shake them indoors. Periodically clean them seriously by hosing outside on a sidewalk or parking lot. They can also be soaked in a plastic wading pool.
• Some teachers use the back of gessoed painting canvas.
• Dupont Tyvec made as house wrap is an alternative to canvas.
• Shower curtain liner plastic may work as a table cover for some things.
• Velcro fastening felt around the edge of the tables can be used to attach covers that have Velcro hook tab attached to the canvas back corners. Sticks along the edge of the canvas allow fastening canvas with c-clamps.

pounding and wedging surfaces

• Do not allow clay pounding on loose canvas covers on tables in a classroom because dust will be liberated.
• Pounding and wedging can be done on thick slabs of concrete or plaster
• Plaster can be tightly covered with heavy canvas to prevent plaster chips from contaminating clay. Dampen the canvas slightly to prevent dust. Scrape clay off with plastic putty knife and sponge it clean when finished.

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© Marvin Bartel, 2001. Last updated December, 2005. All rights reserved. Copying or publishing is prohibited without permission.