A teacher I knew before I even began my career had habitually turned
hers on in the evening without a problem; one night, the KilnSitter cone
failed to trip the off switch and the thing overheated. The result was
a dead kiln and ruined pots, but thank goodness no fire. After that,
she spread the gospel of daytime firings to anyone who'd listen.
Therefore, I always loaded the kiln the night before, and went in early
to fire it throughout the day. Then I could monitor it and reassure the
custodians all was well. There was an exhaust vent above it but there
was always a smell during the water-smoking period. I used a box fan
to blow the smell away.