I have looked after a Theatre Royal for a number of years now and was previously involved with it in my FB licensing officer days.
It is a grade 1 listed building but this has not stopped upgrading all fire safety systems to current standards, granted a lot of this was done during refurbishments. It has a full safety curtain (iron) proscenium sparge pipe, and haystack lantern light providing smoke ventilation above the stage. Fire separation is by a minimum of FD30s or FD60s where applicable.
The alarm system is an addressable system and the two managers on duty carry pagers that display the address of the device activation. The sounders are delayed for three minutes to allow for a staff search and then will operate if no action is taken. Evacuation will initially be aimed at a prompt by a manager addressing the public from the stage but could be initiated by the alarm sounders (regrettably not voice)
The majority of the upgrading was achieved by means of the required fire risk assessment which identified where fire safety standards could be improved and this was accepted by the management.
With regards the concept of panic mentioned by Colin the real issue is human behaviour in fire and crowd movement. I think the study talked about panic being thought of as mass irrational behaviour, however if suddenly faced by a serious fire then it is perfectly rational for a crowd to turn and move quickly, away the issue is can they move quickly and safely through the available exits. (I hope this does not start a massive discussion on panic) there plenty of studies available on this.
For interest the last major restoration costing millions of pounds was replacing gilt work on plaster, chandeliers, original pattern wallpapers, colour scheme and seating.
After the work I was asked to inspect and update the FRA. On walking into the auditorium it was immediately obvious there was not one exit sign visible from any area. Great embarrassment by the architect, during the refurbishment the original illuminated emergency lighting had been removed and some one had forgotten to mention that they were to be replaced. Consequently the plasters had done there job filled in all the holes and then the decorators papered the walls with the expensive hand made original pattern wall paper.
I really felt sorry for the director when I said illuminated signs must be provided on top of his new wallpaper.
So it is possible to get old listed buildings brought up to current standards it just requires a sensible fire risk assessment, a management that cares and of course money.