MS in Fire Protection Engineering
College of Engineering
Frederick Mowrer and Christopher Pascual
California Polytechnic State University at San Luis Obispo recently finished constructing a new multimillion student housing project on campus. One of the six buildings, elewexe or 172B, from this housing complex was selected for a full evaluation of the fire and life safety systems using both prescriptive and performance based approaches. The building is a Type II-B four story dormitory with an R-2 occupancy classification.
For the prescriptive approach, the building was evaluated against the most current editions of the IBC and relevant NFPA code editions for building requirements, sprinkler design and fire alarm and detection. When looking at the building purely for code compliance, everything complies except for administrative controls. The building is constructed within the specifications of the IBC, the egress is adequate for the building, the sprinkler system has a proper design and a strong water supply without a fire pump, and the fire alarm and detection system meets the requirements listed in NFPA 72. One aspect of the building, that is also found in the other buildings within the housing community, is that there are unenclosed stairwells connecting four stories located within the core of the buildings. This is allowed per the 2013 version of the CBC due to an exception because the building is fully sprinklered. This exception causes a lot of emphasis to be put on the sprinklers operating in the event of a fire.
For the performance based analysis is composed of three design fires and a fire model within the report investigates one of the design fire scenarios occurring within the main core and the sprinklers not activating to see if the building design still meets the intent of the code. The results found that in such an event, the available safe egress time (ASET) was less than the required safe egress time (RSET), meaning that in the event that the sprinklers fail in a fire scenario in the core of the building, the building design fails in the intent of the code. Ways to remedy this include increasing administrative controls to limit the amount of fuel in the corridor, increasing testing and maintenance of the sprinkler system to ensure that it functions when needed, an impairment control policy, and adding compartmentation within the building to separate the core stairwell from the rest of the building.