Do Not Fire Toxic, Flammable, or Unknown Materials

All Cautions

Plastics, organic materials, bakeable modeling clay, mothballs and a large variety of materials can decompose under heat causing the release of highly toxic fumes or rapid uncontrollable combustion.
Rocks, marbles, cement and other materials may explode under high temperatures.
Before firing anything but ceramics, glass and metal (obtained from a known reputable source) in a kiln carefully investigate what happens under heat.
This is the sole responsibility of the user.
The kiln is not designed to be used for firing hazardous materials.
Adding propane, wood, charcoal or other materials inteneded to produce a reduction atmosphere can be hazardous if the volume is sufficient. Note that these materials can cause an explosion under certain conditions (just the right amount of air and flammable gasses at just the right temperature) which could cause injury or death. Moreover, a reducing atmosphere can cause premature element failure by reducing the protective oxide coating on the elements. Also note that carbonacious materials will produce poisonous carbon monoxide and highly flammable hydrogen as they decompose at high temperatures. Also note that the "auto-ignition" temperature of flammable gasses is generally above 1400° F.