Statistical Analysis on the Reliability of Sprinkler Systems: Study on a Risk-Based Evacuation Safety Design Method

Abstract

To evaluate the importance of fire protection systems objectively in evacuation safety planning of building fires, authors have proposed a methodology for selecting both design fire scenarios and design fire simultaneously for performance-based fire safety design according to acceptable evacuation risk in fire, which we call risk-based evacuation safety design method or R-B ESDM in abbreviated term. An important factor when using the R-B ESDM is to set the reliability of sprinkler systems. Although several studies exist on the reliability of sprinkler systems, there is no study that looks into the relations of design fire and design fire scenarios. In order to introduce the reliability of sprinkler systems to R-B ESDM, the data of the national fire reports have been statistically analyzed by classifying the fires in the sprinklered spaces into three patterns: “fires that sprinklers extinguished,” “fires that sprinklers suppressed,” and “fires that sprinklers failed to control.” The probabilities of the three patterns have been calculated by using the number of fires according to the burned area. As a result, if the burned area for effective suppression is defined as less than 4 m2, the reliability of effective sprinkler activation turns out to be approximately 83 %.