5_定量火灾风险评估.pptxVIP

Chapter 5Quantitative Fire Risk Assessment;5.1 Overview In this chapter, quantitative fire risk assessment is introduced. The term quantitative fire risk assessment refers to an assessment involving numerical quantifications not only of the probability a fire hazard, or fire scenario occurring, but also the consequences of that fire hazard or fire scenario. ;By multiplying the numerical values of probability and consequence each fire scenario is given a numerical fire risk value. By accumulating the sum of the risk values from all probable fire scenarios we can obtain an overall fire risk value. The overall fire risk value can be used for comparisons with those of alternative or code-compliant fire safety designs.;In general there are two ways to perform systematic quantitative fire risk assessments as follows: 1. by using a checklist to go through a list of potential fire hazards and the quantitative assessment of their fire risks; 2. by using an event tree to go through a set of potential fire scenarios and the quantitative assessment of their fire risks.;In both these methods, the values for the probability and consequence parameters are obtained from statistical data, if they are available, or from subjective judgment, if such data are not available. (仅在我们本课程的讲解中，采用了统计或主观估计的方式，火灾的结果还可以通过确定性的分析计算获得);5.2 Checklist Method As was discussed in Chapter 4, the checklist method employs the creation of a checklist of potential fire hazards and the consideration of fire protection measures, either in place or to be added, to arrive at an assessment of the fire risks. The creation of a checklist of potential fire hazards allows a systematic check of potential fire hazards that are in place.;The listing of fire protection measures alongside with the potential fire hazards allows a quick check of any safety deficiencies and any need to provide additional fire protection measures to minimize the risk. The checklist method, therefore, is an enumeration of potential fire