Will haze set off fire alarms or smoke detectors?

It can, and this is one of the most important questions to address during venue advance. Haze is completely safe and non-toxic, but certain types of smoke detectors (particularly photoelectric detectors) can interpret haze particles as smoke and trigger the fire alarm system.

The standard procedure is to coordinate with the venue in advance. Most venues that regularly host events with production lighting have a process for temporarily disabling smoke detectors in the event space, often requiring a fire watch (a security guard acting as a human fire detector) to be present during the event. Some venues include this at no cost; others charge for it. In the worst cases, detection systems may be building-wide rather than zoned, making the process impractical. Always ask the venue about their haze policy during the site visit, well before the event.