NFPA Standard 92B presents computational methods for determining the position of a smoke layer in a large-volume space. Although NFPA 92B is a guide to smoke management design, the methods have been adopted, with certain modifications, by model building codes and are mandated for use in atriums and large-volume spaces. This paper makes use of a recently developed CFD fire model to assess the NFPA 92B calculation methods. A total of 13 simulated tests were conducted. Results suggest that the NFPA 92B Equation 9 method may not predict the fastest filling of an enclosure within the range of aspect ratios provided in NFPA 92B.

Units: SI