MS in Fire Protection Engineering
College of Engineering
Frederick Mowrer and Christopher Pascual
The purpose of this report is to analyze the Warren J Baker Center for Science and Math on the California Polytechnic State University, San Luis Obispo campus. Baker Science is primarily used for classroom and laboratory instruction of college students, with study spaces, faculty oﬃces, and assembly spaces. There are mechanical, electrical, and storage spaces ancillary to the main building functions. The building comprises six ﬂoors that are between 23,000 and 44,000 ft2. The ﬁrst ﬂoor contains classrooms, faculty oﬃces, mechanical/electrical spaces, and an auditorium with ﬁxed seating. An atrium connects ﬂoors two through ﬁve. There are walkways running down the center of the atrium with openings on both sides. These ﬂoors all contain a mix of classrooms, laboratories, faculty oﬃces, study spaces, and supporting mechanical, electrical, and storage rooms.
The prescriptive analysis of the Baker Science building determines if the building construction complies with the applicable codes and standards. These codes and standards cover life safety, ﬁre suppression, ﬁre alarm and detection, and structural requirements. The life safety section analyzes the ability of the building to safely evacuate occupants in a timely manner. This is accomplished with code-speciﬁed stair and door widths, exit locations, and exit ﬁre rating requirements. The building is protected throughout with an automatic wet pipe sprinkler system, fed from a ﬁre pump on the ﬁrst ﬂoor. The ﬁre pump is supplied from a city water loop to the north of the building. All sprinklers in the building are quick response K-5.6 sprinklers. The ﬁre suppression system activates the ﬁre alarm system in the event of a ﬁre. The alarm system can also be activated with smoke alarms, heat alarms, and manual pull stations. The generation of any part of the ﬁre alarm system in the atrium will activate the passive smoke control system. This system opens roof vents that allow smoke to escape, and also opens doors at the bottom of the atrium to provide makeup air. Doors to the wings of the building are released and closed to reduce the travel of smoke to the east and west wings. The structural ﬁre protection codes provide occupancy separation requirements, and limit building height and area based on construction type.
The performance based analysis seeks to determine how well the building systems can handle a real-life ﬁre scenario, with a focus on building occupants being able to safely evacuate the building in the event of a ﬁre. The ability to safely exit the building is based upon the requirement for tenability to be maintained in the egress route for the entire time it takes for evacuation to be completed. The performance analysis in this report centers around two design ﬁres: one in the atrium, and one in the lobby outside the assembly space. The design ﬁres represent scenarios that would challenge the ﬁre protection capabilities of the building, while still having a probability of occurring. Small ﬁres or ﬁres in unoccupied spaces were not analyzed since they would be unlikely to test the limits of the building’s ﬁre protection systems. The design ﬁre in the atrium exposed occupants to smoke and combustion products, and activated the atrium smoke control system. The smoke venting was inadequate to remove the smoke created by this design ﬁre, resulting in smoke accumulation that limited the visibility of occupants egressing on the sixth ﬂoor. The available safe egress time is 3.23 min after ignition, based on the minimum visibility of 4 m being lost on the sixth ﬂoor, while that ﬂoor has a required safe egress time of 3.96 min. The design ﬁre in the lobby outside the auditorium also exposed occupants to smoke, limiting visibility. The available safe egress time in the lobby is 2.00 min, at which point the 13 m visibility limit is no longer maintained. The required safe egress time is 8.64 min from the time of ignition, signiﬁcantly longer than the time available to occupants.
Prescriptive analysis of the Baker Science building determined that the building was adequately built to the relevant life safety and ﬁre codes. The performance based analysis discovered some shortcomings in the building design. These faults were primarily centered around tenability time for evacuating occupants in the building. On the sixth ﬂoor in the atrium, occupants experienced reduced visibility that could impede their ability to safely ﬁnd the exits and safely escape. The cause of the reduced visibility was the buildup of smoke from the ﬁre, which in turn was caused by inadequate smoke removal by the smoke control system. As a passive system without fans, the smoke can only be removed at a limited rate. One solution to this would be to install additional passive smoke vents. A better solution would be to install powered smoke vents with a rating capable of evacuating adequate smoke from a challenging design ﬁre. Inadequate visibility was also the conclusion of the second design ﬁre. The tall ceiling outside the auditorium ﬁlled with smoke, limiting the visibility of evacuating occupants. Installing smoke control capability in the lobby could remedy this deﬁciency. An easier solution would be to install doors in the auditorium that do not egress into the lobby. This would allow auditorium occupants to avoid the smoke entirely, while reducing the congestion in the lobby for people evacuating from other parts of the ﬁrst ﬂoor. The Baker Science building serves as an example of properly executed code implementation, with failings that can be exposed with demanding design ﬁres.