MS in Fire Protection Engineering
College of Engineering
Frederick Mowrer and Christopher Pascual
A comprehensive fire protection and life safety evaluation has been performed for the Robotic Manufacturing Science and Engineering Laboratory (RMSEL) at Sandia National Laboratories (SNL). The evaluation considered both prescriptive and performance based aspects. Current codes, such as the 2012 International Building Code and the 2013 version of NFPA 13 – Standard for the Installation of Sprinkler Systems, are generally the basis for the prescriptive evaluation even though they are not the code of record for the building. Use of current codes for this evaluation is mostly for academic reasons. Nevertheless, the facility is generally compliant with the provisions of the current codes. Fire modeling has been used to evaluate the performance of the smoke control system in the atrium. RMSEL is a three-story building with an atrium that communicates with all three floors. As such, the atrium is required to have a smoke control system designed in accordance with “generally accepted and well-established principles of engineering relevant to the design.” The smoke control system for RMSEL essentially transitions the heating, venting, and air conditioning (HVAC) system to supply 100% outside air and exhaust 100%. As designed, it is not certain that the smoke control will maintain a tenable environment. For this reason, fire modeling has been used to characterize the conditions resulting from a fire in the atrium. To characterize the benefit of the smoke control system, four runs scenarios have been evaluated. The first scenario assumed the fire burned unmitigated. The second scenario assumed that the sprinklers controlled the heat release rate of the fire. A third scenario considered only the smoke control system activated (i.e., no sprinklers) and the last scenario considered both sprinklers and smoke control. Results of the fire modeling, combined with results from simulated egress times, shows that in general, it takes more time than available to safely egress certain area prior to the loss of tenability. Nevertheless, the smoke control system combined with sprinkler control of the fire extended the available safe egress time longer than the required safe egress time for all but the areas in the immediate vicinity of the fire. The smoke control system provides benefit. This analysis assumed tenability is lost when visibility is less than 13 m, a conservative value. Fire modeling was conservative as it assumed a higher than expected heat release rate, and the soot yield was an average of yields for different foams. It is recommended that the facility stakeholders address the backup power deficiency for the smoke control. Consideration should also be given to running the fire models with less conservatism to better characterize the egress times.