About 1985 I was instructed to vacuum the computer room. It was one of the old-style computer rooms with an elevated floor
the cabling was run under, and positive pressure airflow that blew upward through the machines.
The 16' x 16' office was adjacent to, and had windows between the two rooms.
Both rooms were protected by a LARGE Halon gas system. About 10 minutes into the vacuuming, the sensors mistook the dust
that made it through the vacuum for smoke. WHOOOOOSH! :

Did I do that?
I looked through the window into the office.. Every piece of paper, whether on a desk, pinned to a bulletin board, or taped to
the wall, was swirling around in a cyclone. It kicked up a LOT of dust.
While helium gas causes your voice pitch to go way up, this halon gas did the opposite.
It turned everyone's voice down an octave or so.
I think they decided to damp mop from that time on...