Historic buildings used for purposes such as museums, libraries, exhibits and similar uses less than 3,500 square feet (325.5 m2) per floor and under four stories in height, shall be regulated as a Group B occupancy. Adequate means of egress shall be provided and shall, as applicable, include:
- a means of maintaining doors in an open position to permit egress,
- a limit on building occupancy to an occupant load permitted by the means of egress capacity,
- a limit on occupancy of certain areas or floors, or
- supervision by a person knowledgeable in the emergency exiting procedures.