This information also applies to glass separator.
Kiln wash does not melt at high temperatures and thus forms a protective barrier between kiln shelves and ceramic glaze.
Do not apply kiln wash to the bottom of a ceramic fiber kiln such as the Paragon SC-2 or Home Artist. However, you should apply kiln wash to the bottom of firebrick kilns.
Do not let kiln wash splash onto the walls of the kiln when applying it to the kiln bottom. You can protect the walls with a piece of cardboard. Kiln wash that has splashed onto the walls may eventually end up in an element groove. This could burn out an element.
Do not apply kiln wash to the posts. Apply it to the top of each shelf but not to both sides. Kiln wash on the underside of a shelf will flake onto the ware underneath.
Let the kiln wash dry overnight. You can speed drying by placing shelves in the kiln and heating to around 200 degrees F. for an hour or so. The kiln-washed shelves are still wet if they are cool to the touch.
Hold porcelain and stoneware away from the kiln when wiping off kiln wash from freshly fired pieces. If you wipe off the kiln wash while holding the pieces above the kiln, the dust can settle into an element groove and destroy an element.