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The link between performance based fire safety design and risk assessment is outlined. Present risk assessment methods in areas outside fire safety engineering as well as some of the more important existing risk assessment studies of building fires are briefly reviewed. An attempt is made to link various risk assessment methods, such as the analytical, singlescenario safety index fi method and the multi-scenario, event-tree evaluation approaches, to different levels of fire safety design.Uncertainties, sensitivity and importance are central issues in the utilization of risk assessment results. Methods of uncertainty analysis are summarized and linked to practical design formats. The paper concludes by demonstrating some available results and by summarizing some of the advantages and limitations of risk assessment in fire safety engineering.

SUMMARYThe state-of-art of reliability studies in the area of fire-exposed structures or structural members is illustrated, taking examples from published papers concerning load-bearing building structures of steel, reinforced concrete, and wood. In parallel, trends are described in the present development of rational structural fire design methods, principally adapted to modern loading and safety philosophy for the non-fire state. Statistically deriued results arepresented for fire-exposed, insulated steel structures in office buildings, giuing the breakdown of the total variance in maximum steel temperature and load-bearing capacity into component uariances as a function of the insulation characteristics. The safety index and probability of failure are compared numerically for different fire design procedures. The data presented are examples of the information which is required as input in a qualified systems analysis of fire exposed load-bearing structures.

A B S T R A C TA methodology for deriving design values for occupational safety in public buildings based on risk is presented together with an illustrative example. With knowledge of the design values and chosen characteristic values the corresponding partial coefficients are automaticallv defined. The characteristic values can be chosen as an uvver 80th or 95th -percentile of each distribution. The derivation of the design values is performed using a FOSM (First Order Second Moment) method. The safety level of the building is expressed as a value of the reliability index , f3. In the example case a target p-value is chosen to 1.4 which is approximately equivalent to a probability of failure of 8 % on condition that a fire has started. K E Y W O R D S : fire, evacuation, partial coefficient, risk, reliability index, FOSM