Effects of User Dependence on the Prediction Results of Visibility in Fire Simulations

Abstract

To improve the reliability of safety assessments in domestic performance-based designs (PBDs), the problem of the input parameters being dependent on fire-simulation users was quantitatively analyzed. Thus, the results of statistical analyses of domestic PBD reports evaluated over the last 5 years were examined. It was determined that the uncertainties of the input parameters might have a relatively larger influence on the statistical deviations than the measurement uncertainties. Accordingly, a sensitivity analysis was performed by considering the statistical deviations of the input parameters that could greatly influence the prediction results of visibility, which are important for the available safe egress time. The main results were as follows: a large change in visibility was observed owing to deviations of the heat release rate and soot yield. Based on this study, it is expected that more accurate results can be obtained if the objectivity of input parameters determined by user dependence can be secured in domestic PBDs.

Effects of Optical Properties of Smoke Particles on Fire Detection Characteristics predicted by a Fire Dynamic Simulator Model

“…In Korean PBD, fire simulations are the main method used to evaluate time-related factors (ASET and RSET) for the safety of people during fires. In particular, the open-source Fire Dynamics Simulator (FDS), developed by the National Institute of Standards and Technology, United States (NIST), is mainly used [6,7,8].Through fire simulations, researchers examine the time distributions of physical properties and chemical species related to various risk factors such as heat, smoke, and toxic gas, that prevent occupants from evacuating to a safe place by determining how quickly these factors worsen. In particular, predicting the distribution of smoke concentration within a specific space when a fire occurs is crucial for safe evacuation and human safety.…”

“…In Korean PBD, fire simulations are the main method used to evaluate time-related factors (ASET and RSET) for the safety of people during fires. In particular, the open-source Fire Dynamics Simulator (FDS), developed by the National Institute of Standards and Technology, United States (NIST), is mainly used [6,7,8].…”

“…degree of light extinction caused by smoke particles, prediction characteristics can vary according to the optical properties of the smoke particles [7].…”