Fire Protection and Life Safety Analysis Report

Author

AYOUNG YUN, California Polytechnic State University, San Luis ObispoFollow

Date

6-2025

Degree Name

MS in Fire Protection Engineering

College

College of Engineering

Advisor

Frederick Mowrer and Christopher Pascual

Abstract

This report evaluates the fire and life safety performance of the proposed building, a two- story, mixed-occupancy facility designed to serve as a civic and cultural hub. The analysis was prepared to assess compliance with the 2021 International Building Code (IBC), NFPA 13, NFPA 72, and related standards, with a particular focus on areas where occupant egress paths challenge prescriptive limitations. The project includes assembly, business, and storage occupancies, and features a large auditorium, classrooms, an exhibition hall, a restaurant, offices, and a double-height atrium. The building is designed as a non-separated mixed-use facility and is classified under Groups A-1, A-2, A-3, B, and S-1. Prescriptive requirements for fire resistance, construction type (Type IIB), means of egress, and suppression systems are applied comprehensively throughout. The non-separated occupancy strategy triggers the most restrictive provisions across the entire floor plate, including for egress and fire protection. Analysis confirms that the building remains within allowable height and area limitations per IBC Chapter 5, utilizing area increases allowed for frontage (IBC 506.3). Occupancy load calculations total 3,528 people, and the corresponding exit capacity is shown to exceed minimum code requirements on all levels, with configuration reviewed in detail in Appendix B. A thorough structural fire protection analysis evaluates the expected fire performance of key spaces using time- temperature boundary conditions and member-specific thermal degradation modeling. Classrooms, offices, and the exhibition hall were selected as representative zones based on load, usage, and fire hazard diversity. Time-to-failure analysis for primary and secondary structural components demonstrates that key elements meet or exceed expected fire resistance periods within the bounds of anticipated evacuation times, supported by material selection and passive protection detailing. Section 4 presents a robust performance-based design approach to assess tenability during fire scenarios that challenge prescriptive egress provisions. The performance-based evaluation was initiated due to anticipated exceedances in common paths of travel and travel distance limitations, particularly in open-plan areas. Two representative design fire scenarios, one originating in the atrium and the other in the auditorium, were modeled using the Fire Dynamics Simulator (FDS). The simulations included visibility, gas temperature, and smoke layer height as key tenability metrics. The design’s conservative assumptions regarding occupant travel speeds and fire growth rates further affirm life safety compliance. Results demonstrated the Available Safe Egress Time (ASET) relative to the Required Safe Egress Time (RSET), maintaining tenability for the duration of the evacuation. For Design Fire Scenario 1, the ASET was calculated as 1 minute 40 seconds, limited by visibility. This ASET is shorter than the RSET of 1 minute 56 seconds (100 seconds of egress initiation time of the last person in the office room with fire direct cue + 16 seconds of travel movement time). Although visibility near the exit door has already dropped below 33 feet, occupants would likely still be able to evacuate without being hindered by visibility, toxic gases, or temperature, since they are already close to the exit. However, no safety margin is provided in this scenario. For Design Fire Scenario 2, it was concluded that occupants in the office unit could safely evacuate within 4 minutes 32 seconds (83 sec to sprinkler activation + 90 sec to waterflow switch initiation + 10 sec to notification activation + 60 sec for pre-movement time + 29 sec for travel egress time), which is less than the available safe egress time (ASET) of 4 minutes 50 seconds. The building’s fire suppression system includes a fully sprinklered wet-pipe system designed per NFPA 13, with the Ordinary Hazard Group 2 classification applied to high-risk zones. Hydraulic calculations identified a system demand of 370 GPM at 68 psi, requiring the integration of a 500 GPM fire pump due to limitations of the city’s public water supply (1,200 GPM @ 55 psi residual). A dedicated fire pump room with a 1-hour rated separation is provided. The fire alarm and notification system include a Simplex 4100ES FACP, manual pull stations, horn/strobe devices, smoke detection per NFPA 72, and a voice/alarm communication system serving Group A spaces with occupant loads exceeding 1,000. Pathway survivability and annunciation features meet Level 1 and Level 2 standards where required. In conclusion, the report affirms that both prescriptive and performance-based life safety requirements are satisfied. Areas of performance-based design are well-justified, documented, and exceed minimum safety margins, particularly regarding egress and fire growth modeling. All systems, suppression, detection, compartmentation, and structural resistance work in tandem to mitigate risk and ensure occupant safety.