Building X- Fire Protection System and Life Safety Evaluation

The fire protection and life safety systems for Building X were evaluated for compliance in accordance with applicable nuclear power plant non-power block regulatory requirements, NEIL, INPO, IBC, and NFPA design requirements, codes, and standards. Building X is a one-story building with two internal balconies with 10 occupants per balcony, which is made of non-combustible materials that also has a partial basement with concrete walls (is normally unoccupied), which houses potable water pumps and piping for the facility. Building X falls under the definition of mixed occupancy per the International Building Code (IBC) and the Life Safety Code (LSC). Since Building X has an automatic supervised sprinkler system throughout the facility, the requirement for the building to have separated 2-hour fire resistant rated construction has been relaxed to a separation of occupancies of 1-hour fire resistant rated. Building X has a total gross building area of 75,674 SF. The highest point of the building is 28 ft. There are 15 horizontal exit discharges that serve as primary exits for a calculated building load of 970 occupants. These 15 exits are protected by either a 1 or 2-hour fire wall. However, the total building population of 970 occupants egressing through the subject 7 exits at any given time was target sample for evaluation. The fire protection and life safety systems were found to be in compliance with all the aforementioned design requirements, codes, and standards. The prescriptive requirements for occupancy classification, construction type, structural fire protection, egress systems, fire alarms, and fire protection were reviewed in great detail. The wet pipe sprinkler system in the room was evaluated and it was determined the sprinklers would actuate well before the Tenability Factors depicted below would reach levels that would render the room uninhabitable. In addition, one fire scenario depicted below was used in a performance based fire protection analysis to validate the fire protection and life safety systems for the structure by using egress analysis and CFAST fire modeling tools. A fire scenario was selected in accordance with NFPA 101 section 5.5.3.1* which requires that a design fire that is typical for the type of occupancy and activities being performed in an area and reflects the types of fuel sources and ventilation be used as the type of design fire selected. In this scenario, an upholstered chair catches on fire in the large furnished meeting room area with one exit where the door is closed on the northeast side of the building where 18 occupants are attending a meeting. They can exit the meeting room and through one of the two exits out of the larger office area which contains 89 occupants. The dimensions for the meeting room which catches on fire that were captured in the CFAST model to determine ASET were 52 FT X 42 FT with 8 FT ceilings. An Available Safe Egress Time (ASET) was calculated for the large meeting room based on one of the following limiting tenability factors: 1) Time it takes for the soot or smoke layer to descend to 1.8 meters or 6 feet, 2) Time it takes the temperature within the room to exceed 60 Degrees Celsius, 3) time it takes the room where CO2 levels would decrease O2 levels to 12% or lower. The limiting ASET factor (tenability factor) was determined. The Required Safe Egress Time for 18 occupants traveling down one path of egress along the side of the table in the meeting room to one exit where longest travel distance is 52 FT was used to determine the following four RSET elements: Notification time, Reaction Time, Pre-Evacuation Activity, and Travel Time. Since ASET\u3e RSET, the large meeting room met the performance based design requirements. Using this performance-based approach, the fire and life safety systems were validated and shown to perform satisfactorily in the fire scenario presented in the report below