MS in Fire Protection Engineering
College of Engineering
Frederick Mowrer and Christopher Pascual
The MCS Building is a medical clinic facility located in Phoenix, Arizona. It is a four-story building with roughly 40,000 square feet of occupied floor area per story. The MCS Building is connected to an adjoining hospital on all four occupied stories, and is not considered a separate building from the hospital in accordance with the 2012 International Building Code (IBC). However, for the academic purposes of this report, only the fire and life safety features of the MCS Building are discussed, as if it is a separate building. It consists primarily of medical offices and outpatient clinics, and is not used for any inpatient services or other purposes that would cause occupants to be incapable of self-preservation. Construction was completed in 2004, and the building was designed using the 2000 edition of the Phoenix Building Construction Code (PBCC) and Phoenix Fire Code (PFC). These codes are based on the IBC/IFC, with City of Phoenix amendments. However, the fire and life safety analysis of the building in this report is performed using the 2012 edition of the PBCC/PFC.
The prescriptive-based analysis in this report focuses on the structural fire protection, fire suppression systems, fire alarm and detection systems, and egress features of the MCS Building. The analysis demonstrates that the MCS Building is in accordance with all of the requirements of the PBCC for Type I-A construction. The fire suppression systems are installed in the building in accordance with PBCC/PFC requirements, and were designed following the requirements of NFPA 13. There is an automatic fire alarm and detection system as well as an emergency voice/alarm system installed in the MCS Building, in accordance with the PBCC/PFC and NFPA 72. However, candela ratings in Room 2-229 and Room 3-539 should be investigated, and it should be ensured that Room C-201B is provided with visible and audible notification once it is separated from the adjoining office. It should also be ensured that the new linear accelerator rooms are equipped with area smoke detectors. The egress features built into the MCS Building were found to comply with the prescriptive requirements of the PBCC/PFC.
The performance-based analysis in this report investigated the ability of the fire protection systems in the MCS Building to perform satisfactorily in several different fire scenarios. This analysis was completed using the Fire Dynamics Simulator (FDS) program, in conjunction with the Pyrosim graphical user interface and the Pathfinder evacuation simulator. A basic design fire was constructed using data from a NIST workstation fire test, and was situated on each floor of the MCS Building in order to block occupant access to a stairway used for egress. This scenario was applied to each half of the second and third floors, as well as one half of the concourse floor. The properties and location of the fire products and the smoke produced were tracked, along with the relative location of evacuating occupants. For each scenario, it was investigated whether or not tenable conditions were maintained for the occupants during the evacuation process.
The simulations indicated that when tenability is analyzed on this basis, the only concerning scenario was the Southwest Third Floor model. The visibility criterion was violated in the area around occupants queueing for the northeast stairway. However, visibility is not reduced to the point where exit signs near the stairway and horizontal exit are no longer visible. In addition, trained staff is available to facilitate evacuation, and to re-organize queueing so that all occupants are protected by the 2-hour rated horizontal exit wall. For these reasons, this particular violation of the visibility tenability criterion was determined to not be critical with respect to life safety.