Wear firing safety glasses when looking into the firing chamber of a hot kiln.
These glasses filter the infra-red and ultra-violet light, reduces glare, and make pyrometric cones easier to see.
ALWAYS PROTECT YOUR EYES WHEN LOOKING DIRECTLY AT UV SOURCES!
Ultraviolet Keratitis is a painful eye condition that can develop after unprotected exposure to Ultraviolet (UV) rays. Ultraviolet rays, from a variety of sources including welding arcs (arc eye, welder's eye), reflections off the snow (snow blindness), and germicidal UV lamps can damage the corneal epithelial cells and cause them to slough off after several hours. This is similar to having a "sunburn" of the eye. This leaves underlying corneal nerves exposed and damaged, causing symptoms of intense pain, photophobia, and foreign body sensation.