Ceramic pottery kilns are quite safe when you follow some basic safety precautions. However, following these precautions is essential since kilns do involve extremely high temperatures, and firing kilns releases volatile gases into the air. Here are some tips for using your kiln safely.
Even when kilns are adequately insulated, their outer surfaces can become sufficiently hot to cause serious burns if touched or brushed against with bare skin. Therefore kiln gloves or mitts should be worn whenever touching any part of the kiln when it is firing or cooling down. Even after the kiln’s power has been turned off, it will remain very hot for hours. It should not be touched or opened until it has fully cooled ceramic pottery. Also, dark glasses should be used when observing through the kiln spy holes, in order to protect your eyes. Note that regular sunglasses will not serve this purpose, and can actually melt. Using protective glasses also permits you to observe the cone packs better.
It is also necessary to vent a ceramic pottery kiln either by placing it outdoors or else venting it to the outside. All firings release gases which can irritate the body and lungs; some of these may be toxic or lethal if proper safety measures are not observed. You should closely follow the kiln manufacturer’s instruction manual, and use a licensed heating and air-conditioning (HAC) contractor to install the kiln properly. HAC contractors possess the equipment needed to test accurately the adequacy of the ventilation system. Electric kilns should be installed by a qualified electrician, and local electrical and fire safety codes must be followed. Allow at least one foot of clearance all around the kiln and don’t put anything on top of it. You can strike a match in front of the hood of the kiln. If the draw from the hood blows the match out, then the system is ventilating properly. Be sure to always turn on the kiln vent or hood before loading in order to avoid exposure to ceramic glaze dust.
The toxic fumes given off by a ceramic kiln during firing include carbon monoxide released during reduction firing which can be lethal, sulfur dioxide released by firing metal-soluble salts which irritates the lungs and carbon dioxide which can elevate blood pressure dangerously. Therefore, observe these kiln safety tips. Do not operate the kiln in a wet place. Do not allow children or animals near a hot kiln. Never open the door when a kiln is firing. Do not unload a kiln until the kiln’s surface and the fired pieces are completely cool to the touch. Fuel burning kilns must be attended constantly from the beginning of the warm-up period until the flash-point of the fuel has been reached. Electric kilns should not be plugged or unplugged unless the electric circuit is off and they should always be unplugged before making repairs. Be sure to turn all switches off before loading or unloading a kiln.