This is general information, not a substitute for training. Before you load, fire or unload a kiln, read the kiln maker's manual for that exact model and follow your studio's rules. If you are installing a kiln at home, have a licensed electrician and, where required, your local building or fire authority check the setup.
Your two main sources
Kilns differ in size, power, controls and venting, so no general guide can tell you how to run yours. The maker's manual explains clearance from walls, the electrical supply, venting, the controller and maintenance for your model. Studio rules cover who may fire the kiln, which clays and glazes are allowed, when the kiln may be opened and how to report a problem. Keep the manual near the kiln, and ask staff when anything is unclear.
Heat and burns
- The outside of a firing kiln, the lid and the area around it get very hot. Treat the kiln as hot until it has fully cooled.
- Keep anything that can burn well away from the kiln, as the manual directs. Many studios mark a clear zone on the floor.
- Keep children and pets out of the kiln area.
- Don't open the lid early to check on pots. Follow the manual for safe opening temperatures.
- Use the heat-resistant gloves the studio provides when unloading warm ware, and wait if pots are still too hot to handle.
Fumes and ventilation
Firings release water vapor, smoke from burning organic matter and gases from some clay and glaze ingredients. Kilns need ventilation, either a vent system made for kilns or a well-ventilated room, as set out in the manual. A kiln should not fire in a living space or a room people use during the firing without proper venting.
Looking inside
Peepholes let you see cones during a firing, but the glow at high temperatures includes infrared light that can harm your eyes over time. Use eyewear made for viewing kilns, as the manual or studio recommends, and keep glances short. Hot air can blast out when a peephole plug is removed, so stand to the side.
Electrical setup
Most electric kilns draw a lot of power and need their own circuit, the correct wire size and the right outlet or hardwired connection. These details are set by the manual and local codes, not by guesswork. Don't use extension cords or adapters. Turn the kiln off and disconnect power before doing any maintenance inside it.
Safe loading habits
- Fire only work that is completely dry, as covered in the drying guide.
- Use only clays and glazes rated for the firing temperature.
- Keep glaze off feet and shelves, and coat shelves with kiln wash if your studio uses it.
- Load shelves and posts so they are stable, following the manual's layout guidance.
- Keep pots clear of elements and thermocouples.
- Note the time, the firing program and the cones used in a kiln log.
During and after the firing
Many studios require someone to check the kiln at points during a firing. Know where the shutoff is, where the fire extinguisher is kept and who to call if something seems wrong, such as smoke from the controller, a smell of burning wiring or a kiln that won't shut off. If a fire starts, leave and call emergency services.
Clay dust in the kiln room
Kiln wash, sanding and dry clay make fine dust that contains silica. Clean the kiln room with wet methods or a vacuum made for fine dust, and follow the safety data sheets for the materials you use.