So a couple of productions ago, I tried to use fog as atmosphere and got some really great effects. I set it on a good interval that would maintain the atmosphere at a light level, but not go crazy. I also coordinated with the local fire department who instructed us the SOP for fog/haze. Unfortunately, some cast members (teenagers) got ahold of the machine and essentially created a 0 visibility level backstage before the show. This, in turn, set off the fire alarms, and dispatched the fire rescue team. Our theater got slapped with a $300 fine. Me, being in the booth, physically couldn't get to the cast members, and my ASMs backstage couldn't stop them.
Anyways, I'd really like to use some atmosphere in my upcoming production, but my bosses (who hold me directly responsible for the incident) don't want to hear anything about it. What can I do to prevent an accidental tripping of the alarm and to reassure my bosses that everything will be ok?