MS in Fire Protection Engineering
College of Engineering
Frederick Mowrer and Christopher Pascual
The objective of this report is to conduct a thorough analysis and evaluation of the existing fire life safety and fire protection systems in place at the Building located in San Francisco, California. The building is classified as a Type II-A building and serves predominantly as office space. The building is six stories tall with a total gross area of approximately 97,170 SF.
The initial portion of this report concentrates on a thorough prescriptive-based analysis, which provides an evaluation of the egress design, fire alarm system, communication systems, fire suppression system, structural and construction design, smoke control, and flammability requirements. The results of this comprehensive analysis demonstrate that the building complies with the requirements of the applicable building and fire codes.
The subsequent portion of this report provides a performance-based analysis, which evaluates two distinct fire and life safety assessments. The first assessment involved the evaluation of the I.T. room located in the basement, with a focus on identifying potential flashover occurrences, the activation times of smoke and sprinkler detection, and the possibility of secondary ignition. The outcomes of this analysis revealed that flashover is unlikely to occur, with smoke detection activation taking approximately 674 seconds, and sprinkler activation occurring approximately 744 seconds after the onset of the fire. Note that the activation times appear relatively long for a room of this size, which is understood to be primarily due to the inclusion of the fire's incipient slow growth phase. The results also indicated that secondary ignition does occur. These results suggest that the room is vulnerable to a fire scenario that could significantly impact the operations of the business and safety of occupants. To mitigate this risk, it is recommended that a fire protection system, such as a clean agent halon system or CO2 system, be installed to suppress fires and minimize equipment damage. Additionally, regular equipment maintenance performed by qualified professionals should be conducted to minimize the risk of ignition. The room should also be regularly inspected to ensure that the space does not contain large amounts of combustible materials to reduce potential fuel sources.
The second fire scenario involves the atrium, which connects the basement level to the second floor. The design fire occurs at the base of the atrium in the basement. The scenario was assessed using Fire Dynamic Simulator (FDS) and Pathfinder to determine the Available Safe Egress Time (ASET) and Required Safe Egress Time (RSET). The primary objective was to determine whether the ASET exceeds the RSET, thus ensuring that the building and its associated life safety systems can maintain a safe and tenable environment for all occupants to evacuate safely. The ASET analysis will specifically focus on the deployment of the fire-rated shutters to assess whether the conditions on the levels above the fire, as well as the areas remote from the fire, will remain safe and suitable for the evacuation of building occupants. Pathfinder was utilized to determine the RSET, and the results indicated a time of 1034 seconds (~18 minutes) which takes into account a 1.5x safety factor.
ASET was calculated by FDS, which simulated and assessed various tenability criteria, including smoke layer descent, heat exposure, visibility, and carbon monoxide dosing. The results indicated that the ASET could be maintained for 18 minutes for floors and areas remote from the fire. This is primarily due to the activation of fire-rated shutters, which compartmentalized the basement from the floors above. It should be noted that the atrium complies with all applicable prescriptive code requirements. The analysis emphasizes the crucial role of fire safety equipment functioning properly to ensure the safety of occupants within the building. The primary recommendation is to minimize potential ignition sources and fuel sources near the atrium. Additionally, regular equipment inspection and maintenance from qualified professionals should be conducted to ensure that the fire alarm system, automatic sprinkler system, and fire-rated shutters operate properly.