How can I find out the chairs lease of a Conference Room ?
Answers: Easy, call and ask.
There is a breakdown of the amount of space to consider per person for the different ways of setting a room.
You enjoy to keep in mind that you may know how to put 100 people in a room Theatre Style (chairs only) but if you want it set up Classroom Style (table within front of attendees) it would be more space intensive and would probably only accommodate 50 people instead.
The "Occupancy" sign is only that. States how many people are allowed to occupy the room at one time - not the "seating" tenancy.
If you have a source of contact for the conference room they would be able to provide adjectives of the variations of seating/occupants for you.
Call up the place and ask.
Insurance wise they hold to have a notice as to how frequent the conference room can hold and usually a plaque is hanging somewhere in the room itself.