Smoke Detection in a large enclosed venue

[ABLE1 <somewhere@xxxxxxxxxxx>]

Hey guys,

This is a I don't know question and looking for a answer
thingie.  This is not for a project or job just curious.

My brother, (who only guesses an answer since he doesn't
really know one way or the other).  Mentioned to me the
other day that he heard that some large group was playing
at a venue and because of there FOG MACHINE it tripped off
the FIRE ALARM.  He then said that they must have replaced
the smoke detectors to units that can only see smoke and
not FOG.  Well I said to him that they more than likely
turned off the smokes while the FOG was there and then
turned them back on later because the smoke detectors
can't tell the difference between smoke, dust, spiders and FOG.

What this did was made me think what a Alarm Company would do
in the case to actually meet code compliance??

Beam Detectors can maybe be adjusted somehow or to maybe off.

Heat Detectors can surely work and not be effected but for
heat only.  Not a good thing and really not code.

Ionization Smokes maybe not sure............ doubt it.

Turn off, and station multiple human bodies for a fire watch
during the event to yank on a Pull Station if there is a
real fire event observed.

Get a variance with the jurisdiction to allow something other
than smoke detectors during an event that uses FOG Machines.

Anybody know or been involved is something like this??

Again just curious.

Thanks,

Les