MS in Fire Protection Engineering
College of Engineering
Frederick Mowrer and Christopher Pascual
This report provides a fire safety analysis on the Robert E. Kennedy Library located on the Cal Poly University campus San Luis Obispo, California. In the course of this analysis, a prescriptive and performance-based approached was used. The goal was to review and obtain an understanding of the features of the building’s design and use that provide fire safety. During the analysis, areas of deficiency will be identified. Recommendations will be made based on the analysis and the nature of the deficiencies.
The overall goal is to abide by the NPFA Life Safety standard: (1) Protection of occupants not intimate with the initial fire development, and (2) Improvement of the survivability of occupants, intimate with the initial fire development.
These goals can be accomplished by both prescriptive and performance-based codes. Since the library is an existing building, the prescriptive-based codes will apply and the performance analysis will be used to review areas of safety concern. In the prescriptive analysis, the buildings classification and use were established and the rated structural elements were assessed. This included structural typing, egress components, suppression systems, and alarm functions.
On the prescriptive side, the library was built according to the 1976 Uniform Building Code. Any requirements would be held to that code. The use of the International Building Code is only for reference. However, it should be noted that if any changes to the structure or use of the building would require a new code review and possible update to the current code.
The library is a five-story Type I-A building classified as a Group A-2.1 (Group A-3 per IBC). It has a calculated occupant load capacity of 2725 people. While the primary building elements comply with the code, there were some areas of deficiencies. These are mainly egress issue for occupant loads. The two main ones, are a single exit point in the first-floor open courtyard and the lack of egress width capacity on the second-floor. As recommended, a simple fix would be to reduce occupancy capacity or add a second exit to the courtyard.
Since the library is not fully equipped with an automatic sprinkler system, it has some water demand issue. Hydrant flow tests show a water supply of 2590 GPM. The current water supply is well under the IBC and ISO recommendations. While not a requirement for existing buildings, if a sprinkler system was installed, the current water demand would then be able to meet the IBC and ISO recommendations. For the performance-based analysis, the following tenability criterion was established to meet the defined goals: (1) Smoke Obscuration of 13-feet horizontal view or vertical smoke level dropping below 6-feet above floor, (2) Asphyxiant gas: Ct exposure dose of CO at 30,000 ppm-min, and (3) Thermal – ambient air temperature at 6 feet of 140° F.
Three different design fires were developed trying to meet the guidelines in the NFPA Life Safety Code. The first was a fire in the bookstack area of the fourth-floor. The second was a desk fire located at the main entrance causing the front exit and main staircase to be unusable. These two fires are fuel limited fires and not expected to cause flashover. The third fire is one in a smaller room on the fourth-floor. This fire was designed to reach flashover.
After modeling the three fires, the fire progression was compared to the tenability criterion. This was used to determine if RSET met ASET for each of the three different design fires. For design fire 1 (fire in the bookstack area) the ASET was 460 seconds to evacuate the floor while the RSET with a safety margin was 429 seconds. The fire in the bookstack area did not meet the safe egress requirements. For design fire 2 (fire in the front lobby) the ASET was 900 seconds to evacuate the first and second floors while the RSET with a safety margin was 810 seconds. For design fire 3 (fire in study room on fourth floor) the ASET was not established, but it was expected to exceed the RSET with a safety margin value of 612 seconds.
After the performance analysis there were further recommendations in addition to the recommendations for the prescriptive aspects. These include installing additional smoke detectors, equipping the library with an emergency voice alert system, and implementing a written safety plan that includes staff training.