This section is from the book "Modern Buildings, Their Planning, Construction And Equipment Vol6", by G. A. T. Middleton. Also available from Amazon: Modern Buildings.
The lives of so many being at stake, it is obviously the first duty of all responsible to provide and maintain ample and suitable exits for the immediate escape of the people. These exits should, in fact, be sufficient to allow the whole audience, no matter of what size, to leave the theatre in two minutes; for the spread of fire and smoke to all parts of the theatre may be almost instantaneous. But it is not only in the event of fire that ample and easy exits are necessary, for they will be almost equally important in the event of an alarm of fire. A most trivial occurrence will often cause a panic resulting in many deaths; in fact, the majority of fatalities in theatre fires may be attributed to panic. A rush will be made for the exit, some one will stumble over an unseen step, others will fall over the first, and the stream of panic-stricken people will attempt to climb over those fallen, in their mad efforts to reach safety. The consequence of such an occurrence will be that few will reach the outer air before they are overcome by the poisonous fumes of combustion, while if the alarm has been false many will have been crushed to death in the rush and jamb.
It is, then, not only necessary to provide ample exits, but these exits must be as direct and as easy as possible. Careful planning will not only allow the house to be emptied rapidly, but the sense of security thus obtained will go far to prevent panic.
Every division of the house, stalls, pit, dress circle, etc., not omitting orchestra and stage, must each have at least two exits, one of which may also be an entrance. These exits in each part of the house should be as far away from the stage as possible, for it is on the stage that a theatre fire will nearly always originate, and the natural impulse of the people will be to flee in a direction away from the fire. The exits should also be one on either side of the house for each part, and should communicate immediately with the street.